Background
Fluid overload is frequently found in critically ill patients with AKI.
Its associated with increase mortality.
Consequences of fluid overload in organ systems:
Organ consequences.
Consequences Cerebral edema Impaired cognition Delirium
Myocardial edema Conduction disturbance Impaired contractility Diastolic dysfunction
Pulmonary edema Impaired gas exchange Reduced compliance Increased work of breathing
Renal interstitial edema. Reduced RBF Increased interstitial pressure, Reduced GFR ,Uremia
Hepatic edema Impaired synthetic function, Cholestasis
Gut edema Malabsorption , Ileus .
Tissue edema Poor wound healing Wound infection Pressure ulceration
Discussion : The role of fluid therapy in the development of fluid overload :
In critically ill patients, adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or sepsis.
but over time since critically ill patients have a increased capillary leak intravenous solutions will leave the circulation and distribute in the extracellular volume leading to edema and to fluid overload.
These results in impaired oxygen and metabolite diffusion, distorted tissue architecture, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may then contribute to progressive organ dysfunction. overload and outcomes:
There’s a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
patients with fluid overload defined as an increase in body weight of over 10 % had significantly more respiratory failure, need of mechanical ventilation, and more sepsis.
AKI patients with fluid overload had increased 30 day and 60 day mortality.
Among survivors, AKI patients who required renal replacement therapy had a significantly lower level of fluid accumulation at initiation of dialysis and at dialysis cessation than non-survivors.
Renal recovery was significantly lower in patients with fluid overload
Fluid status assessment :
Accurate volume status evaluation is essential for appropriate therapy .
History. And physical examination.
I.e history of CHF or symptoms of heart failure, SOB,PND,
Presence. Of raised JVP, peripheral edema, rales (low sensitivity).gallop rhythm.
Investigation:
CXR ,sign of fluid overload .
BNP :high negative predictive value when low ,high in fluid overload ,heart failure MI,PE,RF.
Bioimpedance vector analysis:
Bioelectrical impedance analysis is a commonly used method for estimating body composition, specifically detecting soft tissue hydration with a 2–3 % measurement error. It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
Thoracic ultrasound :
Sonographic artifacts known as B-lines that suggest thickened interstitial or fluid-filled alveoli can be detected using thoracic ultrasound.
Vena cava diameter ultrasound :
The measurement of the inferior vena cava (IVC) diameter can also be use to assess volume status. Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Management. Of fluids overload:
Diuretic
Extracorporeal therapies :
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
Conclusions :
Several complications like congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function are associated with fluid overload. Fluid overload has also been related to increased mortality. The optimal assessment of volume status in critically ill patients is of vital importance particularly during the early management of these patient.
Level of evidence V.
Rehab Fahmy
2 years ago
Fluid overload is associated with multiple fatal problems could be iatrogenic in ICU setting due to high volume of crystalloid infusion
Diagnosis:
Symptoms and examination
I/O balance daily and cumulative balance
CXR
BNP
it can cause pulmonary edema ,congestive heart failure,myocardial edema ,bowel and hepatic congestion ,cerebral edema
% of fluid overload adjusted for body weight if>/= 10% ,ass with high mortality
calculated using this formula:
% Fluid overload= ((total fluid in-total fluid out)/ admission body weight × 100)
management:
Diuretics:Furosemide:high doses can cause myocardial ischemia,
in case of resistance:add thiazides
if no response start CRRT
Nasrin Esfandiar
2 years ago
Fluid overload is associated with adverse outcome in critically ill patients in ICU. Although adequate fluid therapy is necessary for proper cardiac outcome, systematic BP, renal perfusion and prevention of AKI, but capillary leak may lead to edema formation. Fluid overload results in impaired oxygen delivery, disturbed cell to cell interactions and may lead to organ dysfunction such as cerebral edema, myocardial edema, pulmonary edema, hepatic and gut congestion and reduced RBF or GFR. Fluid overload and outcome:
Fluid overload more than 10% is associated with increased respiratory failure, ARDS, sepsis, AKI and higher mortality. Fluid overload recognition and assessment:
This requires an accurate calculation of intakes and outputs. Useful definitions include:
1- Daily fluid balance.
2- Cumulative fluid balance: sum of daily fluid balance during a period of time.
3- Fluid overload: indicates a degree of peripheral edema or pulmonary edema.
4- Fluid accumulation: positive fluid balance.
5- Percent of fluid overload adjusted for BW: cumulative fluid balance presented as a percent with increased mortality over 10%.
6- %Fluid overload= [(total intake-total output)/admission BW*100] Fluid status assessment:
1- History and physical examination.
2- CXR
3- Natriuretic peptides
4- Bio-impedance vector analysis.
5- Thoracic ultrasound to define B-lines.
6- Vena cava diameter ultrasound: normal is 1.5-2.5 cm. More than 2.5 cm suggests volume overload Fluid overload management:
1- Diuretic therapy: especially loop diuretics.
2- Extracorporeal therapies such as CRRT (in form of SCUF or CVVH) or IHD. Conclusion:
Fluid overload results in increased mortality and complications such as CHF, pulmonary edema, impaired wound healing and bowel function. Loop diuretics have limited effectiveness and RRTs are often required.
The level of evidence is 5.
Fatima AlTaher
2 years ago
In critically ill patients, maintaining acheiving blood volume to maintain COP and tissue perfusion is a life saving . AKI complicating critical illness carries poor prognosis specially when complicated with volume overload.Hense it’s extremely important to evaluate volume status and calculate and maintain adequate fluid balance to improve prognosis of critically ill patients.
Fluid therapy aim at acheiving balance between tissue perfusion that will be impaired if low fluid volume is used and avoid hypervolemia that’s commonly complicated with prepheral tissue oedema , pulmonary congestion and delayed weaning from MV,cerebral oedema leading to increase ICT, fits and coma , hepatic congestion impairing liver synthetic function and in sever cases HE or DIC can develop, GIT congestion leading to malabsorption , tissue oedema impair tissue healing and predispose to ulceration
Evaluation of volume overload
1- History: fluid intake , fluid loss ( vomiting , diarrhea)
2- physical examination: signs of hypervolemia include
– Heart: tachycardia , S3 gallop murmer
– Lung : pulmonary congestion or edema manifested as crepitation s and decrease air entery respectively.
Abd : ascites , enlarged tender liver
LL : odema
Investigations
1- chest : CXR , CT , US
all are non invasive and can evaluate volume status.
2- Heart : non invasive investigations as echo
and invasive investigations as pulmonary catheter to evaluate pulmonary capillary wedge pressure.
– pelvi- abd US
– Bioimpedence .
Lap investigations useful for volume status assessment include
1- B natriuretic peptide.
Management of volume overload
1- fluid restriction.
2- Diuretic therapy.
3- Extracorporeal removal of excess fluid
Level of evidence: 5
Jamila Elamouri
2 years ago
Fluid overload in the ICU: evaluation and management
Fluid overload recognition and assessment
Accurate documentation of intakes and outputs are required for fluid overload recognition and assessment in critically ill patients.
Useful definitions
1- Daily fluid balance: daily difference in all intakes and all outputs, which frequently does not include insensible losses.
2- Cumulative fluid balance: sum of each day fluid balance over a period of time.
3- Fluid overload: implies a degree of pulmonary edema and peripheral edema.
4- Fluid accumulation: positive fluid balance, with or without linked fluid overload.
5- Percentage of fluid overload adjusted for body weight:
Accumulative fluid balance that is expressed as a percent. A cutoff ≥ 10 % has been associated with increased mortality. Fluid overload percentage can be calculated using the following formula:
% fluid overload
= [(total fluid in – total fluid out)/admission body weight x 100]
Fluid status assessment
There are several methods to evaluate fluid status; However, most of these tests currently used are fairly inaccurate.
· History and physical examination
Medical history, symptoms, and signs along with routine investigations (like CXR, ECG, BNP) use to detect the probability and differentiate heart failure from other causes of dyspnea in the emergency were evaluated by many studies. Importantly, signs like pulmonary rales, lower extremity oedema, and jugular venous distention have significant limits for assessing fluid overload.
· Chest radiography
Most widely used. Radiological signs of fluid overload include dilated upper lobe vessels, cardiomegaly, interstitial oedema, enlarged pulmonary artery, pleural effusion, alveolar oedema, prominent superior vena cava, and Kerley lines. 20% of heart failure patients had negative chest X-ray findings. these findings do not correlate with PCWP. Also, they are affected by the technique and the patient’s status. Portable CXR, reduce the sensitivity of finding fluid overload, and pleural effusion can be missed in the supine position. The presence of X-ray findings increased with the severity of heart failure.
· Natriuretic peptides:
A high level of BNP can be found in fluid overload. Although, there are other conditions that may increase BNP like:
1- MI
2- Pulmonary embolism
3- Obesity
4- CKD
The greatest utility of BNP levels is in the absence of elevation since low BNP levels have a high negative predictive value for excluding heart failure diagnosis. While high BNP levels can be non-specific for volume overload.
· Bioimpedance vector analysis
It is used to detect body composition, specifically detecting soft tissue hydration with a 2–3 % error. Bioimpedance vector analysis (BIVA) measures the whole-body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration. Clinical information is compared with the patterns of healthy populations. A study comparing the BIVA to the CVP; found that The agreement between BIVA and central venous pressure indications was good in the high CVP group, moderate in the medium CVP group, and poor in the low CVP group.
· Thoracic ultrasound:
PCWP and fluid accumulation in the lungs have been correlated with the presence of B-lines (“comet-tail images”) in patients with congestive heart failure. The comet-ail-score was found to correlate with extra-vascular lung water determined by PiCCO system. PCWP, x-ray findings.
· Vena cava diameter ultrasound
IVC diameter was used to assess volume status. The normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); in case of volume depletion an IVC diameter < 1.5 cm. IVC diameter > 2.5 cm suggests volume overload.
IVC diameter and right ventricular diameter evaluation could be a practical noninvasive method for fluid status estimation and response to therapy in critically ill patients.
Fluid overload management
A- Diuretic therapy:
Loop diuretics, remain a valid therapeutic alternative for relieving symptoms and improving fluid overload in congestive heart failure and in patients with AKI. There is no evidence that favors ultrafiltration over diuretic use in volume overload patients with or without AKI. Despite that more patients developed AKI during diuretic treatment, numerous studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes. Some empirical observations have shown that a urine output of 3–4 ml/kg/h rarely causes intravascular volume depletion.
They could be administered by bolus or continuous infusion. There has been controversy about which strategies is better.
It is important to assess acid-base status and electrolyte levels as the diuretics used are associated with electrolyte disturbances.
v Hypokalemia can be avoided with oral potassium or the use of spironolactone.
v Hypomagnesemia is frequently found during diuretic therapy, magnesium replacement can be achieved either orally or IV, with 20 – 30 mmol per day.
v chloride losses exceed sodium losses and hypochloremic metabolic alkalosis develops; this is usually corrected with the administration of potassium chloride and magnesium chloride.
Torsemide it could be more efficacious than furosemide in patients with heart failure (decreased mortality, hospitalization and, NYHA class).
In AKI patients, as compared with torsemide the use of furosemide was associated with a significant improvement in urine output.
In AKI, the response to furosemide may be reduced by:
1- reduced tubular secretion of furosemide.
2- Blunted response of Na-K-2Cl co-transporters at the loop of Henle.
This requires higher doses of furosemide that may increase the risk of ototoxicity and can cause myocardial dysfunction secondary to vasoconstriction caused by furosemide.
B- Extracorporeal therapies
Refractory medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies. Management of fluid balance is obligatory with the goal to improve pulmonary gas exchange and organ perfusion while maintaining stable hemodynamic parameters. The optimal RRT modality has not been yet defined. CRRT has advantages over IHD. The choice of modality depends on the patient’s status, availability, and staff experience.
CRRT is an independent predictor of renal recovery among survivors. Slow continuous ultrafiltration (SCUF) is usually performed with a low blood flow rate (50 to 100 ml/min) and ultrafiltration between 100 and 300 ml/h according to fluid balance necessities. CVVH is another modality of CRRT which allows continuous fluid, electrolyte, and toxin clearance.
Another option for treating patients with fluid overload is the new smaller and more portable devices like the Aquadex FlexFlow System (Baxter Healthcare) however, yet associated with an adverse effects of special interest and a serious study product-related adverse events
Conclusion:
Fluid overload is associated with increased mortality. The principal aspect of fluid management is to maintain hemodynamic stability and organ perfusion. Loop diuretics play an important role in fluid overload management, but their effect may be blunt in advanced AKI. Continuous renal replacement therapy with different modalities can be used to provide controlled fluid overload management.
Fluid overload in critically ill patient is associated with adverse outcome as impaired O2 delivery, organ dysfunction as cerebral edema and pulmonary edema
Fluid overload is associated with increase in mortality.
Can be assessed by:
clinically
chest X-ray
Natriuertic peptides
Chest USG
Ultrasound to assess Inferior vena cava diameter normally 1.5 to 2.5 cm more than 2.5 indicates volume overload
Managed by :
Diuretics
Extracorporeal Therapy as dialysis or CRRT
Ghalia sawaf
2 years ago
recent studies have highlighted the role of fluid overload on adverse outcomes
Restrictive fluid management strategies are beneficial during ARDS and following major surgery
The administration of crystalloids solutions expands the extracellular compartment, but over time due to capillary leak, intravenous solutions distribute in the extracellular volume leading to edema and to fluid overload.
These results in
1. impaired oxygen
2. Impaired metabolite diffusion,
3. distorted tissue architecture,
4. obstruction of capillary blood flow and lymphatic drainage,
5. disturbed cell to cell interactions
6. then contributed to progressive organ dysfunction
Edema is attributed to a combination of
increased capillary permeability to proteins
increased net trans-capillary hydrostatic pressure
Fluid overload and outcomes Bouchard et al., have shown that patients with fluid overload (increase in body weight of over 10 %) had significantly
more respiratory failure,
need of mechanical ventilation,
more sepsis.
Renal recovery was significantly lower in patients with fluid overload
In children, a multicenter prospective study found that the percentage of fluid accumulation at initiation of CRRT was significantly lower in the survivors (14.2 % ±15.9 % vs. 25.4 % ±32.9 %, P=0.03)
.Several studies have provided evidence associating positive fluid balances with poorer respiratory outcomes.
In one of these studies, septic shock patients with acute lung injury who received conservative fluid management after initial fluid resuscitation had lower in-hospital mortality
In another study, Wiedemann et al. randomized 1000 patients to either a conservative or to a liberal strategy of fluid management. Patients with conservative fluid strategy had:
• lower cumulative fluid balance,
• improved oxygenation index and lung injury score,
• increased number of ventilator-free days,
• reduction in the length of ICU stay.
• did not increase the incidence or prevalence of shock during the study
• did not increase the need for renal replacement therapies
Fluid overload recognition and assessment
. Mehta RL and Bouchard J proposed some useful definitions
1. Daily fluid balance:
2. Cumulative fluid balance
3. Fluid overload
4. Fluid accumulation:
5. Percentage of fluid overload adjusted for body weight:
A cutoff of ≥10 % has been associated with increased mortality.
. Fluid status assessment
1- History and clinical examination
along with routine diagnostic studies (chest radiograph, ECG, and serum(BNP)) were evaluated in a meta-analysis.
• past history of heart failure (positive LR = 5.8; 95 % CI, 4.1–8.0);
• A low serum BNP proved to be the most useful test (serum BNP <100 pg/mL; negative LR=0.11; 95 % CI, 0.07–0.16)
Butman et al. found that the presence of jugular venous distension, at rest or inducible, had a sensitivity (81 %), and a specificity (80 %) for elevation of the pulmonary capillary wedge pressure (≥18 mmHg).
Using hepato-jugular reflux and Valsalva maneuvers, Marantz et al. showed that these maneuvers were valid in the diagnosis of congestive heart failure in acutely dyspneic patients, with low a sensitivity (24 %) and a high specificity (94 %)
2- Chest radiography
1. dilated upper lobe vessels,
2. cardiomegaly,
3. interstitial edema,
4. enlarged pulmonary artery,
5. pleural effusion,
6. alveolar edema,
7. prominent superior vena cava,
8. and Kerley lines.
However, up to 20 % of patients diagnosed with heart failure had negative chest radiographs at initial emergency department evaluation.
Additionally, patients with PCWP values ≥30 mmHg where radiographic pulmonary congestion was absent in 39 % of patients
The X-ray technique impacts the detecting of volume overload. Ex, pleural effusion in intubated supine patient
3-Natriuretic peptides
High levels of BNP can be found with volume overload;
• Differential diagnosis,
• myocardial infraction
• pulmonary embolism
The greatest utility of BNP levels is in the absence of elevation, since low BNP levels have a high negative predictive value for excluding heart failure diagnosis
. On the other hand, high BNP levels can be nonspecific for volume overload [26].
4-Bioimpedance vector analysis
commonly used method for estimating body composition,
It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information
BIVA was examined as an indicator of fluid status compared to central venous pressure (CVP) in 121 critically ill patients
In this study patients were classified in three groups according to their CVP value:
• low (0 to 3 mmHg);
• medium (4 to 12 mmHg); and
• high (13 to 20 mmHg).
The agreement between BIVA and CVP indications was good in the high CVP group, moderate in the medium CVP group, and poor in low CVP group.
5-Thoracic ultrasound
PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines (“comet-tail images”)
Agricola et al., used thoracic ultrasound to detect “comet-tail images” authors found significant positive linear correlations between comet-tail images score and extra-vascular lung water determined by the PiCCO System, between comet score and PCWP, and between comet-tail images score and radiologic sings of fluid overload in the lungs
6- Vena cava diameter ultrasound
can also be use to assess volume status.
• Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium);
• volume depletion is considered with an IVC diameter <1.5 cm
• an IVC diameter >2.5 cm suggests volume overload.
Lyon et al. evaluated the inferior vena cava diameter (IVCd) during inspiration (IVCdi) and during expiration (IVCde), before and after blood donation of 450 mL. The difference was as (5.5 mm and 5.16 mm, respectively).
Zengin et al. evaluated the IVC and right ventricle (RVd) diameters and diameter changes compared to healthy volunteers.
the IVC during inspiration and expiration, and right ventricule diameter were significantly lower.
After fluid resuscitation, there was a significant increase in mean IVC diameters during inspiration and expiration as well as in the right ventricule diameter
Fluid overload management Diuretic therapy
Diuretics, especially loop diuretics,
At this time, there is no evidence that favors ultrafiltration over diuretic use in volume overload patients
Numerous studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes
What should be the goal of urine output when using diuretics to manage fluid overload?
For some empirical observations 3–4ml/kg/h
Diuretics could be either administered by bolus or using a continuous infusion.
In one study diuretic infusion was associated with greater diuresis and this was achieved with a lesser dose
infusion was also associated with fewer adverse events such as worsening AKI, hypokalemia, and ototoxicity.
However, in the DOSE-AHF study, authors found that patients with acute heart failure may benefit from an initial bolus strategy
In order to avoid hypokalemia, administration of oral potassium it is easy.
Another strategy is the use of potassium-sparing diuretics like spironolactone.
Hypomagnesemia is frequently found during diuretic therapy, magnesium replacement can be achieved either intravenously or orally, typically with 20–30 mmoL per day.
Finally in some patients, chloride losses exceed sodium losses and hypochloremic metabolic alkalosis develops; this is usually corrected with the administration of potassium chloride and magnesium chloride.
A recent comprehensive review have shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide,
The reduced response to furosemide in AKI patients often requires the use of higher doses that may increase the risk of ototoxicity,
High doses of furosemide may also result in myocardia dysfunction secondary to furosemide induced vasoconstriction.
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of CRRT
CRRT provides a slower fluid removal over (IHD) resulting in more hemodynamic stability and better fluid balance control,
advantages of CRRT over IHD include:
• slower control of solute concentration
• reduce the risk of cerebral edema
Some large observational studies have suggested that CRRT is an independent predictor of renal recovery among survivors
Slow continuous ultrafiltration (SCUF) is a type of continuous renal replacement therapy that is usually performed with low blood flow rates (50 to 100 ml/min), and ultrafiltration rates between 100 and 300 ml/h according to fluid balance necessities.
Continuous veno-venous hemofiltration (CVVH) is another CRRT technique that allows meticulous, minute-to minute control of fluid balance by providing continuous fluid, electrolyte, and toxin clearance.
Another option for treating patients with fluid overload are the new smaller and more portable devices like the Aquadex FlexFlow System (Baxter Healthcare).
Costanzo et al. compare adjustable ultrafiltration using a small ultrafiltration device to the use of intravenous loop diuretics. The authors found a trend to longer time to recurrence of heart failure within 90 days event after hospital discharge in patients treated with the ultrafiltration device, and fewer heart failure and cardiovascular events.
Changes in renal function and the 90-day mortality were similar in both groups. However, more patients who were randomized to adjustable ultrafiltration experienced an adverse effect of special interest (p = 0.018) and a serious study product-related adverse events (p =0.026)
**Level 5 of evidence
Wael Jebur
2 years ago
Fluid management is crucial in post operative and critically ill patient in the setting of Intensive care unit. As restoring normal cardiac and organs function depends entirely on fluid status and hydration level of the organs, similarly cardiac function and cardiac output is depending on maintaining intra-vascular volume status.
On the other hand volume overload is linked to formation of edema , swelling of cells and organ dysfunction secondary to compression of blood vessels and deranged Hydrostatic vs oncotic pressure in encapsulated volume in particular.
Therefore,ascertaining volume status is pivotal in managing those patients, as its turning point in the whole management. Assessment of volume status:
History and clinical examination is standerd in the care of hypervolemic patient.
Markers of volume status:
Pro-BNP is widely to reflect the volume staus , as it reflective of hypervolemia.
Bio-impedance vector analysis.
Thoracic US is a sensitive tool to assess volume status , as it would be reflecting engorgement of interstetium or fluid filled alveoli featuring B-lines (Comit-tail image ) consistent with hypervolemia.
Vena cava diameter :
less than 1.5 cm reflect hypovolemia and more than 2.5 cm , hypervolemia.
management:
Diuretics are still widely used in Hypervolemia.
A urine output of 3-4 ml/Kg/day is safe, as its matching capillary refill rate and would not result in hypovolemia.and intravascular depletion.
furosemide activity is futile in AKI due to decreased excretion of furosemide into tubular fluid and impaired response of Na-K-2Cl Co transporter.
high doses of furosemide might result in ototoxicity and cardiac toxicity.
It can be given in infusion or boluses.with debatable effect of each modality.
Rihab Elidrisi
2 years ago
fluid overload is one of the major complications post-RTX
increase the accumulation of fluid especially in AKI and sepsis with fluid accumulation in the extracellular space.
AKI and fluid overload carry high mortality rates,
fluid overload assessment and recognition:
full physical examination and history taking to see if there is any symptoms or sign of fluid overloads like an SOB or lower limb oedema or raised JVP.
chest x ray demonstrating pulmonary venous congestion, ECG demonstrating atrial fibrillation, and reduced serum BNP (negative predictive value) can be used to assess fluid overload. The significance of lower limb edema, an increased JVP, and pulmonary rales is restricted. 20% of individuals with heart failure exhibit negative chest x-rays. Daily and cumulative fluid balance assessments are also significant methods for determining fluid overload. In conjunction with CVP, bioimpedance vector analysis (BIVA) can identify soft-tissue hydration with a measurement error of 2% to 3%. In congestive heart failure, a thoracic ultrasonography revealing B-lines, signifying fluid-filled alveoli, is beneficial. Ultrasound can also be used to measure the diameter of the inferior vena cava (>2.5 cm indicates fluid excess).
Mohamad Habli
2 years ago
Fluid overload has been correlated with negative effects. Restoring cardiac output, blood pressure, and renal perfusion necessitates adequate fluid resuscitation. Inadequate fluid evacuation is linked to peripheral and pulmonary edema, which delays weaning from artificial breathing or wound healing. The goal of the study was the assessment and management of fluid overload in ICU patients.
Fluid resuscitation in patients with sepsis and those at risk for AKI leads to elevated extracellular volume, edema in different organs (hepatic renal, pulmonary, myocardial, gut and tissue) and fluid overload, resulting in impaired oxygenation, distorted tissue architecture, disturbed cell to cell interaction, with capillary blood flow and lymphatic obstruction, and organ dysfunction, especially in encapsulated organs like the liver and kidneys.
Fluid overload and outcomes:
Fluid overload and outcomes: In the presence of fluid overload, AKI is associated with increased 30-day and 60-day death rates. In the presence of ARDS, a greater positive fluid balance is related with increased mortality.
Fluid overload recognition and assessment:
This can be done by evaluating history and physical examination – history of heart failure, paroxysmal nocturnal dyspnea, third heart sound gallop on auscultation, chest x ray demonstrating pulmonary venous congestion, ECG demonstrating atrial fibrillation, and reduced serum BNP (negative predictive value) can be used to assess fluid overload. The significance of lower limb edema, an increased JVP, and pulmonary rales is restricted. 20% of individuals with heart failure exhibit negative chest x-rays. Daily and cumulative fluid balance assessments are also significant methods for determining fluid overload. In conjunction with CVP, bioimpedance vector analysis (BIVA) can identify soft-tissue hydration with a measurement error of 2% to 3%. In congestive heart failure, a thoracic ultrasonography revealing B-lines, signifying fluid-filled alveoli, is beneficial. Ultrasound can also be used to measure the diameter of the inferior vena cava (>2.5 cm indicates fluid excess).
The management of fluid excess includes the use of diuretics and extracorporeal therapy. Loop diuretics are symptomatic relief diuretics that can be administered either bolus or continuous infusion (infusion associated with lesser AKI, hypokalemia and ototoxicity and greater diuresis while boluses are better in acute heart failure). Potassium loss, hypomagnesemia, hypochloremia, and metabolic alkalosis are side effects of diuretics that can be treated with potassium chloride and magnesium chloride. Torsemide has been reported to be more successful in heart failure, while furosemide has a larger urine output in patients with acute kidney injury (AKI), but the response is diminished, necessitating higher doses that increase the risk of ototoxicity and cardiac dysfunction.
CRRT and IHD are used to increase pulmonary gas exchange and organ perfusion in diseases resistant to conventional therapy. Compared to IHD, CRRT delivers slower fluid evacuation with superior fluid management and hemodynamic stability. SCUF is performed with low blood flow and ultrafiltration rates, whereas CVVH offers continuous fluid, electrolyte, and toxin clearance. The Aquadex FlexFlow system is a portable option for treating individuals with fluid excess.
In conclusion, fluid overload is correlated with congestive heart failure, pulmonary edema, poor wound healing, reduced bowel function, and impaired cognition, and it increases the risk of death. Consequently, evaluation of fluid status and prompt treatment can prevent or mitigate the negative effects of fluid excess.
Adequate fluid resuscitation is essential to the restoration of cardiac, intravascular effective volume, and good peripheral perfusion. fluid overload is one of the major complication with acute renal failure, leads to overload, pulmonary edema. Fluid overload increases the critically ill patient. So timely fluid assessment for overload and timely management is crucial.
If patient is making output can start diuretics, otherwise need to initiate ultrafiltration.
level of evidence V
Manal Malik
2 years ago
Summary of Acute kidney injury and critical ill patient usually develop fluid overload
Management of fluid balance is crucial in critical ill patients’ management as fluid overload present as peripheral oedema and pulmonary oedema.
This study focuses on the evaluation and management of fluid overload in the intensive care unit. Discussion:
The role of fluid therapy in the development of overload.
Critical ill patients such as patient with cardiogenic or septic shock are in need to restore circulation (BP and cardiac output) and renal perfusion.
Adequate treatment with intravenous solutions can also prevent or limit subsequent AKI.
Critical ill patient has an increased capillary leak. intravenous solutions leading to oedema and fluid overload. These result in impaired oxygen and metabolite diffusion, distorted tissue architecture.
Obstruction of capillary, blood flow and lymphatic damage. These effect usually in encapsulated organ such as kidney or liver. Fluid overload and outcomes:
Several observational studies have demonstrated a correlation between fluid overload and mortality in critical ill patients with acute respiratory distress syndrome, acute lung injury, sepsis and AKI.
Lungs are one of the organs in which adverse effects are most evidence.
Several studies have provided evidence associating positive fluid balance with poor nephrology outcome. Fluid status assessment:
Several methods exist to evaluate fluid status although most of them are inaccurate.
Clinical evaluation include history and physical examination include: dyspnoea, pulmonary rate, lower limb oedema and distended jugular veins.
Chest radiograph: signs of overload in radio phrenic angles, distended upper loop vessels, cardiomegaly, intestinal oedema, enlarge pulmonary artery, pleural effusion, alveolar oedema, prominent superior vena cava, kidney lines. Natriuretic peptides high BNP can be found with volume overload and also in pulmonary embolism, myocardial infraction and renal failure.
Bioimpedance vector analysis is a commonly used method for estimating body composition, specifically detection soft tissue denaturation with a 2-3% measurement error.
Thoracic ultrasonographic artifact known as B-lines that suggest thickened interstitial or fluid filled alveolar can be detected using thoracic ultrasound PCWP and fluid in lungs have been correlated with the presence of B-lines in patients with congestive heart failure.
Vena cava diameter ultrasound normal dimeter of IVC is 1.5-2.5 cm
Volume deletion is considered with an IVC diameter > 2.5cm suggest volume overload. Fluid overload management:
Loop diuretic use to treat fluid overload are load in patients with AKI. number of studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume normal is associated with improved outcomes. Urine 2output 3-4 ml/kg /h rarely cause intravascular volume depletion.
Diuretics can be given ones or continues infusion. Infusion fewer adverse event such as worsen AKI, hypokalaemia and ototoxicity.
Although patient with HF benefit from initial bolus strategy.
High doses of frusemide may also result in myocardial dysfunction secondary to fursmide induced vasoconstriction Extracorporeal therapy:
Refractory overload to medical therapy
Requires use of extracorporeal therapies such as CRRT or IHD.
In absence of definite data to support the use of particular type of renal
replacement therapy one should consider CRRT and IHD.
Other modalities of RRT can be used such as ( SCUF , CCVH).
Other option for treating patient with fluid overload are the new smaller and more portable devices like Aguadex Flex Flow System.
Conclusion:
Fluid overload complication included congestive heart failure, pulmonary oedema, delay wound healing, tissue breakdown and impaired bowel function.
Fluid overload increased the mortality especially among critical ill patients.
Volume status assessment in critical ill patient play an important role of early management of these patients.
Loop diuretics are frequently used as initial therapy to treat critical ill patients with fluid overload.
RRT use to treat fluid overload in critical ill patient and ultrafiltration dependon accurate estimation of patient fluid status
evidence level is 5
Mohamed Saad
2 years ago
Fluid overload in the ICU: evaluation and Management.
Fluid overload is one of the major problem associating with AKI patients in critical area which is associated with increasing in morbidity and mortality , so we should try to keep our patients euvolemic by Strict fluid intake and output chart, diuretics in need or CRRT. Many studies have shown an association
between fluid overload and mortality. Discussion:
Adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or septic shock so we should be oriented about how to evaluate the volume status, to select appropriate solution for volume repletion, and maintenance and modulation of the tissue perfusion.
Fluid therapy such as crystalloid which used to expand intravascular volume but it may has adverse effects in critically ill due to sepsis itself which increase capillaries leak to interstitial tissue and lead to fluid overload which affect metabolic status and organ dysfunction.
Edema is attributed to a combination of increased capillary permeability to proteins and increased net trans-capillary hydrostatic pressure through reduced pre-capillary vasoconstriction. Fluid overload and outcomes.
Many studies have shown a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
Fluid overload associated with high hospital stay, high mechanical ventilator. Fluid overload recognition and assessment.
Mainly depends on strict intake and output chart, we should keep in mind that if percentage of fluid overload adjusted for body weight above 10% is associated with high mortality.
Which calculated by % Fluid overload (total fluid in−total fluid out) /admission body weight x 100. Fluid status assessment. A-History and physical examination:
past history of heart failure, SOB, paroxysmal nocturnal dyspnea and third heart sound gallop which indicate HF.
Signs: such as presence of jugular venous distension, at rest or inducible, had a sensitivity (81 %), and a specificity (80 %). B-Chest radiography.
Radiographic sings of volume overload include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent
superior vena cava, and Kerley lines.
But the sensitivity, specificity, and accuracy of supine chest X-ray was reported to be as low as 60 %, 70 %, and 67 % respectively. C-Natriuretic peptides.
High with CHF and ESRD patients but it in not sensitive but low BNP levels have a high negative predictive value for excluding heart failure diagnosis. D-Bioimpedance vector analysis.
Simply, It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
The combined evaluation of peripheral tissue hydration (BIVA)
and central filling pressure (CVP) could provide a useful clinical assessment instrument in the planning of fluid therapy in critically ill patients, particularly in those with low CVP. E-Thoracic ultrasound.
Thickened interstitial or fluid-filled alveoli appear as Sonographic artifacts which is called as B-lines (“comet-tail images”) F-Vena cava diameter ultrasound.
Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Ultrasonography can measure IVC diameter and right ventricle diameter which is considered practical noninvasive instrument for fluid status estimation and for evaluating the response to fluid therapy in critically ill patients. Fluid overload management. Diuretic therapy.
Many studies shown that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes.
Some empirical observations have shown that a urine output of 3–4 ml/kg/h rarely causes intravascular volume depletion as capillary refill can meet such rates in almost all patients.
Furosemide electrolyte imbalance should be followed as hypokalemia, hypomagnesemia and hypochloremic metabolic alkalosis. Extracorporeal therapies.
CRRT over IHD include: a slower control of solute concentration avoiding large fluctuations and fluid shifts, which reduce the risk of cerebral edema, also SCUF or CVVHF can be used . Conclusions.
Volume overload in critical patients is associated with high morbidity and mortality rate, history, physical examination and investigational equipment such as CXRY, USG of chest , IVC diameter assessment are so important to assess and manage the volume overload which is started by diuretics and if resistant we can start to remove the fluid by extracorporeal therapies.
level of evidence :V
Zahid Nabi
2 years ago
Fluid replacement in critically ill patients is mainstay of treatment and to create that delicate balance to avoid fluid overload is real challenge for clinicians.This review has shed light on this important aspect of management.
In critically ill patients, adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or septic shock. The administration of crystalloids in these sick patients can lead to tissue edema owing to the associated increased capillary permeability ultimately leading to organ dysfunction.
Fluid overload is not only a consequence of fluid therapy but also occurs during severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products and altered organ microcirculation.
Fluid overload and outcomes
Several studies have shown increased mortality associated with fluid overload in critically ill patients.Lungs are one of the organs in which adverse effects of fluid overload are most evident, which can lead to acute pulmonary edema or acute respiratory distress syndrome.
Fluid overload recognition and assessment
This can be done by different ways like daily measurement of fluid in and out, Cumulative fluid balance assessment, percentage of fluid overload adjusted for body weight.
History and physical exam.
Diagnostic tests like
CXR
ECG
Serum BNP
Bioimpedance vector analysis
Bioelectrical impedance analysis is a commonly used method for estimating body composition, specifically detecting soft tissue hydration with a 2–3 % measurement error.
It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
Bioimpedance vector analysis (BIVA) measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration.
Thoracic ultrasound
Sonographic artifacts known as B-lines that suggest thickened interstitial or fluid-filled alveoli can be detected using thoracic ultrasound. PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines (“comet-tail images”) in patients with congestive heart failure.
Vena cava diameter ultrasound.
The measurement of the inferior vena cava (IVC) diameter can also be use to assess volume status. Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Fluid overload management
Diuretic therapy
Diuretics, especially loop diuretics, remain a valid therapeutic alternative for relieving symptoms and improving pathophysiological states of fluid overload such as congestive heart failure and in patients with AKI.
Diuretic infusion or bolus dose has not shown much difference in terms of outcome.
At the same time, there is no evidence that favors ultrafiltration over diuretic use in volume overload patients with or without AKI in terms of less progression of AKI, improved clinical out- comes or reduce incidence of AKI .
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
The choice of therapy like CVVH, SCUF etc depends upon clinical condition , available resources and expertise.
The ultimate goal is to preserve tissue perfusion, optimizing fluid balance by effectively removing fluid without compromising the effective circulating fluid volume; therefore, meticulous monitoring of fluid balance is critical for all patients.
Fluid overload has also been related to increased mortality. The optimal assessment of volume status in critically ill patients is of vital importance particularly dur- ing the early management of these patients.
Fluid overload has been seen to be associated with adverse outcomes. Adequate fluid resuscitation is essential to restore cardiac output, blood pressure and renal perfusion. Inadequate fluid removal is associated with peripheral edema and pulmonary edema, retarding weaning from mechanical ventilation or wound healing. The study focused on the evaluation and management of fluid overload in ICU patients.
Role of fluid therapy in fluid overload development: Fluid resuscitation in patients with sepsis and those at-risk of AKI leads to elevated extracellular volume, leading to edema in different organs (hepatic renal, pulmonary, myocardial, gut and tissue) and fluid overload, resulting in impaired oxygenation, distorted tissue architecture, disturbed cell to cell interaction, with capillary blood flow and lymphatic obstruction, leading to organ dysfunction, especially in encapsulated organs like liver and kidneys.
Fluid overload and outcomes: Fluid overload in critically ill patents with AKI, ARDS, acute lung injury, and sepsis is associated with increased mortality. AKI is associated with increased 30-day and 60-day mortality, in presence of fluid overload. Higher positive fluid balance in presence of ARDS is associated with increased mortality.
Fluid overload recognition and assessment: It can be done by assessing history and physical examination – history of heart failure, paroxysmal nocturnal dyspnea, third heart sound gallop on auscultation, chest x ray showing pulmonary venous congestion, ECG showing atrial fibrillation, reduced serum BNP (negative predictive value), can be utilized to assess fluid overload. Lower limb edema, elevated JVP, and pulmonary rales have limited role. 20% of heart failure patients have a negative chest x-ray. Daily fluid balance and cumulative fluid balance assessment are also important tools to assess fluid overload. Bioimpedance vector analysis (BIVA) detects soft-tissue hydration with 2-3% measurement error, and can be useful if used in combination with CVP. Thoracic ultrasound showing B-lines, suggesting fluid-filled alveoli, are useful in congestive heart failure. Inferior vena cava diameter using ultrasound is another way to assess volume status (>2.5 cm suggesting fluid overload).
Fluid overload management includes use of diuretics and extracorporeal therapies. Diuretics include loopdiuretics for relieving symptoms, which can be given either as bolus or continuous infusion (infusion associated with lesser AKI, hypokalemia and ototoxicity and greater diuresis while boluses are better in acute heart failure). Diuretics are associated with potassium loss, hypomagnesemia, hypochloremia, and metabolic alkalosis which can be managed with potassium chloride and magnesium chloride. Torsemide has been found to be more effective in heart failure while furosemide use had better urine output in AKI patients, although the response is reduced and hence requires higher doses increasing the risk of ototoxicity and myocardial dysfunction.
Extracorporeal therapies like CRRT (continuous renal replacement therapies) and intermittent hemodialysis (IHD) are utilized in conditions refractory to medical therapies to improve pulmonary gas exchange and organ perfusion. CRRT provides slower fluid removal with better fluid control and hemodynamic stability than IHD. Slow continuous ultrafiltration (SCUF) is performed with low blood flow rates and low ultrafiltration rates while continuous veno-venous hemofiltration (CVVH) provides continuous fluid, electrolyte, and toxin clearance. Portable devices like Aquadex FlexFlow system are also available to treat patients with fluid overload.
To conclude, fluid overload is associated with congestive heart failure, pulmonary edema, poor wound healing, impaired bowel function, and impaired cognition, and leads to increased mortality. Hence assessment of fluid status andtimely action can prevent or minimize adverse effects of fluid overload.
What is the evidence provided by this article?
Level of evidence: Level 5 – narrative review
Mohammad Alshaikh
2 years ago
Summarise this article Introduction: Volume overload is frequent complication faced in ICU settings, with difficulty in recognition, and it has been associated recently with adverse outcomes and mortality. The role of fluid therapy in the development of fluid overload: Adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion prevent acute kidney injury in patients with cardiogenic or septic shock. over time patients experienced an increased capillary leak intravenous solutions will leave the circulation and distribute in the extracellular volume leading to edema and to fluid overload, results in impaired oxygen and metabolite diffusion, distorted tissue architecture, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may then contribute to progressive organ dysfunction. Fluid overload and outcomes: Fluid overload %= total fluid in−total fluid out /admission body weight x100. A formula used to estimate fluid overload if more than 10%, associated with adverse outcomes, such as difficult to wean from mechanical ventilator, organ dysfunction ie.. AKI, requirement of renal replacement therapy, and increased mortality. Fluid overload recognition and assessment: 1. Daily fluid balance: daily difference in all intakes and all outputs, which frequently does not include insensible losses. 2. Cumulative fluid balance: sum of each day fluid balance over a period of time. 3. Fluid overload: usually implies a degree of pulmonary edema or peripheral edema. 4. Fluid accumulation: positive fluid balance, with or without linked fluid overload. 5. Percentage of fluid overload adjusted for body weight: cumulative fluid balance that is expressed as a percent. A cutoff of ≥10 % has been associated with increased mortality. Clinical assessment: – History and physical examination: history of heart failure, raised JVP, lower limb edema, pulmonary crackles, SOB, PND’s…etc. – Chest x ray: dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines. However 20 % have negative imaging, sensitivity of 60%, specificity of 70% and 67% accuracy. – Natriuretic peptides (BNP): Has a high negative predictive value, positive results indicated Rt. Ventricular strain- PE, volume overload, and MI. – Bioimpedance vector analysis: measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration, when combined to CVP measurement could provide a good clinical assessment for volume overload. – Thoracic ultrasound: can detect a B-lines “comet tail images” that suggest thickened interstitial or fluid-filled alveoli. – Vena cava diameter ultrasound: diameter < 1,5 cm indicates volume contraction, and >2,5 cm indicates volume overload. Fluid overload management: – Diuretics- loop diuretics, potassium sparing diuretics. – Extracorporeal therapy – Intermittent HD , or continuous renal replacement therapy (CVVH, SCUF). Conclusion: Volume overload is a frequently faced problem in ICU with high adverse outcomes, difficult to detect and needs an excellent knowledge to define and treat. Renal replacement therapies are often required for optimal volume management in critically ill patients with fluid overload.
What is the evidence provided by this article? Level of evidence V, erratic review.
Huda Al-Taee
2 years ago
Summary:
In critically ill patients, adequate fluid resuscitation is essential to restore cardiac output, systemic blood pressure, and renal perfusion. Achieving an appropriate level of volume management requires knowledge of the underlying pathophysiology, evaluation of volume status, selection of appropriate solution for volume repletion, and maintenance and modulation of the tissue perfusion.
Fluid overload and outcomes:
Several observational studies have demonstrated a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
Fluid overload recognition and assessment:
Requires accurate documentation of intakes and outputs; however, there is a wide variation in how this information is recorded, reviewed and utilized.
Some useful definitions:
Daily fluid balance: difference in all intakes and outputs, frequently not including insensible losses.
Cumulative fluid balance is the sum of each day’s fluid balance over time.
Fluid overload: usually implies a degree of pulmonary edema or peripheral edema.
Fluid accumulation: positive fluid balance, with or without linked fluid overload. Percentage of fluid overload adjusted for body weight: cumulative fluid balance that is expressed as a percent. A cutoff of ≥10 % has been associated with increased mortality. Fluid overload percentage can be calculated using the following formula:
% Fluid overload=((total fluid in- total fluid out)/admission body weight*100).
Fluid status assessment:
history and examination: symptoms, signs, and routine diagnostic studies.
Chest X-ray: Radiographic signs of volume overload include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines.
Natriuretic peptides: High levels of BNP can be found with volume overload, and other causes: e myocardial infarction, pulmonary embolism, and obesity.
Bioimpedance vector analysis: specifically detecting soft tissue hydration with a 2–3 % measurement error, noninvasive, inexpensive and highly versatile test.
Thoracic ultrasound: Sonographic artifacts known as B-lines that suggest thickened interstitial or fluid-filled alveoli can be detected using thoracic ultrasound.
Vena cava diameter ultrasound: Normal diameter of IVC is 1.5 to 2.5 cm; volume depletion is considered with an IVC diameter <1.5 cm, while an IVC diameter >2.5 cm suggests volume overload.
Extracorporeal therapies: The choice of the initial modality needs to be based on the availability of resources, local expertise, the individual needs of the patients, and the patient’s hemodynamic status. CRRT or IHD can be used.
Level of evidence:
Level 5 (review article).
Assafi Mohammed
2 years ago
Summary of the article “Fluid overload in the ICU – evaluation and management” Fluid overload in the ICU; Underlying
· A consequence of fluid therapy.
· Severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products and altered organ microcirculation.
Fluid overload; outcome
· Several observational studies have demonstrated a correlation between fluid overload and mortality in critically ill patients(ARDS, ALI, AKI and Sepsis).
· Body weight of over 10 % had significantly more respiratory failure, need of mechanical ventilation, and more sepsis.
· AKI patients with fluid overload had increased 30 day and 60 day mortality.
· Lower level of fluid accumulation at initiation of dialysis and at dialysis cessation, is associated with better survival.
Fluid overload; Evaluation and assessment:
1. History and physical examination.
· History of heart failure.
· SOB, PND.
· Third heart sound gallop, Pulmonary rales, lower extremity edema and jugular venous distention.
2. Diagnostic studies; ECG, CXR and serum BNP.
3. Bioimpedance vector analysis (BIVA); transforms electrical properties of tissues into clinical information. Bioimpedance vector analysis (BIVA) measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration.
4. CVP;
· low (0 to 3 mmHg).
· medium (4 to 12 mmHg).
· high (13 to 20 mmHg).
5. The combined evaluation of peripheral tissue hydration (BIVA) and central filling pressure (CVP) could provide a useful clinical assessment instrument in the planning of fluid therapy in critically ill patients.
6. Thoracic ultrasound; Sonographic artifacts known as B-lines(“comet-tail images”), that suggest thickened interstitial or fluid-filled alveoli.
7. Vena cava diameter ultrasound; Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Fluid overload;Management
1. Diuretics; a UOP of 3-4 ml/Kg/hr rarely causes intravascular volume depletion.
2. Ultrafiltration via CRRT, if hemodynamically unstable. Otherwise UF using IHD is an alternative.
3. Adjustable ultrafiltration using Aquadex FlexFlow System (Baxter Healthcare).
What is the evidence provided by this article?
This is a narrative review article.
Level of evidence grade 5.
mai shawky
2 years ago
Club 6; hypervolemia in ICU, diagnosis and management Summary
· Volume overload is one of the most important predictors of patient outcomes in ICU and in critically ill patients.
· Assessment of the volume status is crucial and assessment of the fluid balance (with input and output) is essential.
· Treatment by loop diuretics or CRRT in diuretic resistant cases.
· In case of sepsis, initial fluid resuscitation is essential to maintain organs perfusion and prevent AKI, however later on, the intra-capillary and extra-capillary leak will lead to interstitial edema and escape of fluids extravsacular.
· Fluid overload > 10 % of dry weight is associated with higher mortality and morbidity.
· Fluid balance, total input and output of fluids and daily weight are essential to determine the fluid balance.
· lung is the most sensitive organ to fluid overload with risk of pulmonary edema, increase need for mechanical ventilator and worse outcome.
· Many tools can be utilized as CXR, ecg, lung US, IVC diameter and collapsibility index.
Level of evidence: narrative review (level V)
Hussam Juda
2 years ago
· In acute respiratory distress syndrome and following major surgery, patient may benefit from fluid restriction
· Over load and pulmonary edema in critically ill patients, may retard weaning from mechanical ventilation and wound healing
Discussion
· crystalloids solutions are essential for the treatment of patients with or at risk of AKI, and also in patients with sepsis
· over time due to increased capillary leak, IV fluids will lead to edema and to fluid overload.
· Edema may lead to impaired oxygen and metabolite diffusion, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may lead to progressive organs dysfunction, mainly liver and kidney
· Fluid over load could happen due to severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products
· AKI patients with fluid overload had increased 30 day and 60-day mortality
· patients with septic shock and acute lung injury who received conservative fluid management, had better outcome
· The Vasopressin in Septic Shock Trial (VASST) found that higher positive fluid balance correlated with increased mortality and the highest mortality rate observed in those with high CVP
Fluid overload recognition and assessment
1. Daily fluid balance
2. Cumulative fluid balance
3. Fluid overload
4. Fluid accumulation
5. Percentage of fluid overload adjusted for body weight
Fluid status assessment
· History and physical examination
· Chest radiography. sings of volume overload include:
dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines
· High levels of BNP can be found with volume overload; however, some conditions like myocardial infraction and pulmonary embolism can cause elevated levels of BNP
· Bioimpedance vector analysis
· Thoracic ultrasound
· Vena cava diameter ultrasound Fluid overload management Diuretic therapy:
· some authors advocate that diuretic infusion is superior to boluses since urinary output could be maintain easily
· infusion associated with fewer adverse events such as worsening AKI, hypokalemia, and ototoxicity
· Hypomagnesemia is frequently found during diuretic therapy; magnesium replacement can be achieved either intravenously or orally
· A recent review shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide
· torsemide can be more efficacious than furosemide in patients with heart failure Extracorporeal therapies Advantages of CRRT over IHD include:
· more hemodynamic stability and better fluid balance control
· slower control of solute concentration avoiding large fluctuations and fluid shifts
· allows to perform the treatment with relatively simple and user friendly machines
Slow continuous ultrafiltration (SCUF): usually performed with low blood flow rates (50 to 100 ml/min), and ultrafiltration rates between 100 and 300 ml/h
Continuous veno-venous hemofiltration (CVVH):
New smaller and more portable devices like the Aquadex FlexFlow System
Conclusions
· Congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function are associated with fluid overload
· Fluid overload has also been related to increased mortality
· Loop diuretics are frequently used as the initial therapy to treat critically ill patients with fluid overload
· Renal replacement therapies are often required for optimal volume management in critically ill patients with fluid overload
The level of evidence is 5
KAMAL ELGORASHI
2 years ago
Summary of the Article; Fluid overload is commonly occur in ICU setting specially in patient with AKI, and it should be considered as a mediator of adverse outcome. Discussion; The role of fluid therapy in the development of fluid overload;
Adequate fluid resuscitation is vital in restoring cardiac function and to prevent AKI in the setting of sepsis and septic shock.
To assess the volume needed for replacement you have to know the underline cause, the pathophysiology, and selection of appropriate solution, and tool for assessment of restoration and when to stop.
Administration of crystalloid solution is preferable for restoration of hemodynamics and prevent shock specially in septic shock patient, but in critical ill patient there is risk of oveload from capillary fluid leak.
This may lead to impaired oxygenation, distortion of tissue, diffusion of metabolite, lymphatic obstruction and subsequent organ damage.
Fluid overload is not caused only due to fluid infusion, but also due to capillary leak in sever sepsis.
Fluid overload and outcome;
Several studies show association between fluid overload and increased mortality in critical ill patient with acute respiratory distress syndroe, acute lung injury, sepsis and AKI.
Bouchard et al.; patient with overload of >10% have increase respiratory failure, need for mechanical ventilator, and more sepsis.
Patient with AKI developing overload has an increase 30 days to 60 days mortality.
Renal recovery was frequently slower in AKI patient develop overload.
Several studies show association between overload and poorer respiratory outcome.
In one study patient with septic shock who receive fluid resuscitation and conservative fluid management had a lower in-hospital mortality.
Wiedemann et al,; patients on conservative fluid management had a lower cumulative fluid balance, improve oxygenation index, and lung injury score,increase number of ventilator free days, and reduce ICU stay days, and not associated with increasing shock or the need of RRT.
VASST study; higher positive fluid balance associated with increasing mortality in those with CVP>12 mmHg.
Fluid recognition and assessment;
Dailly fluid balance.
Cumulative fluid balance.
Fluid overload.
Fluid accumulation.
Percentage of fluid overload adjusted to for body weight.
Fluid status assessment;
History and physical examination.
Chest radiograph, (Chest x ray).
Natriuretic peptide, (high level ass with overload).
Bioimpedance vector analysis.
Thoracic US.
IVC US.
Fluid overload management;
Diuretic therapy.
Extracorporeal therapies.
Conclusion; Overload associated adverse effects include; CHF, Pulmonary edema, Delyed wound healing, and impaired bowel function. Accurate assessment of fluid status is vital and monitor fluid replacement is mandatory to avoid complication associated with fluid overload.
Level of evidence ((V))
Hoyam Elamin
2 years ago
Introduction:
Correct fluid volume management requires knowledge of the good knowledge of pathophysiology, volume status assessment, choosing the correct solution for volume replacement, and maintaining tissue perfusion. The crystalloids solutions expands the extracellular compartment, with time and due to increased capillary leak in critically ill patients, the IV solutions leave the intravascular space and distribute in the extracellular space, leading to edema and to fluid overload. This leads to impaired oxygen and metabolite diffusion, tissue disruption, impaired capillary blood flow and lymphatic flow, disturbed intrecellular interactions, all leading to progressive organ dysfunction. These effects are seen mostly in encapsulated organs.
Fluid overload (an increase in body weight of over 10 %) in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI, led to higher incidence of respiratory failure, need of mechanical ventilation, and sepsis. AKI patients with fluid overload had higher 30-day and 60-day mortality.
Studies suggested that positive fluid balances is associated with poorer respiratory outcomes and that conservative fluid management protocols had lower cumulative fluid balance, better oxygenation index and lung injury score, more ventilator-free days, and reduced ICU length of stay.
Fluid overload recognition and assessment:
Fluid overload diagnosis and assessment in critically ill patients requires meticulous intakes and outputs charting. The following definitions are helpful: Daily fluid balance: this is the difference in intakes and outputs, it does not usually include insensible losses. Cumulative fluid balance: sum of fluiddf balances over a period of time.
· Fluid overload: usually implies a degree of pulmonary edema or peripheral edema.
· Fluid accumulation: this is the positive fluid balance, with or without fluid overload.
· Percentage of fluid overload adjusted for body weight: this is the cumulative fluid balance expressed as a percent. ≥10 % is associated with higher mortality.
There are several methods to evaluate fluid status; however, most of the tests currently used to evaluate fluid overload are inaccurate.
These include:
· History and physical examination along with routine diagnostic studies. Pulmonary rales, lower extremity edema, and jugular venous distention may have significant limits in fluid overload assessment.
· High levels of Natriuretic peptides: however, many clinical conditions are associated with high and low levels BNP such as myocardial infraction and pulmonary embolism obesity, and renal failure. low BNP levels have a high negative predictive value for excluding heart failure diagnosis. On the other hand, high BNP levels can be nonspecific for volume overload.
· Bioimpedance vector analysis: the Bioelectrical impedance analysis is commonly used for estimating body composition, it detects soft tissue hydration with a 2–3 % measurement error. It is a non-invasive, non-expensive, and highly versatile test.
· Thoracic ultrasound: the B-lines (comet-tail images) on thoracic US suggest thickened-fluid-filled alveoli.
· Vena cava diameter ultrasound: the IVC diameter can also be used for volume status assessment. Normal diameter of IVC is 1.5 to 2.5 cm. Bedside IVC and right ventricle diameter measurement is a practical non-invasive test for assessment of fluid status and the response to fluid therapy in critically ill patients.
Fluid overload management:
· Diuretic therapy:
· Diuretics, especially loop diuretics, relieve symptoms, and improve effects of fluid overload. There is no evidence favouring ultrafiltration (UF) over diuretic use in volume overload patients with or without AKI. Aggressive use of loop diuretics associated with improved outcomes. Diuretics infusion- compared to boluses -resulted in more diuresis with a lesser dose, and fewer adverse side effects. Electrolytes levels and acid-based status should be monitored closely. High doses of furosemide may result in MI due to furosemide-induced vasoconstriction.
· Extracorporeal therapies
· If medical therapy fails, extracorporeal therapies such as continuous renal replacement therapies (CRRT) can be used. Studies found that CRRT is an independent predictor of renal recovery among survivors. CRRT and IHD should be considered as complementary therapies. CRRT is preferred to intermittent haemodialysis (IHD) as it offers:
· Slower fluid removal leading to more hemodynamic stability,
· Better fluid status control,
· Slower control of solute concentration avoiding large fluctuations and fluid shifts, which may lead to cerebral edema,
· Great flexibility of treatment adjustment to patient’s needs at any time,
· Ability to perform the treatment with simple and user friendly machines.
Other modalities are: Slow continuous ultrafiltration (SCUF) (a type of CRRT that is usually performed with low blood flow rates), Continuous veno-venous hemofiltration (CVVH), and the new smaller and more portable devices like the Aquadex FlexFlow System.
Ban Mezher
2 years ago
Fluid overload associated with increase mortality among ICU patients.
Fluid restriction during ARDS & after major surgery have a beneficial effect of through reducing duration of mechanical ventilation & rate of cardiopulmonary complications.
Role of IV fluid with volume overload development:
Critically ill patients have increased capillary leak leading to shifting fluid from intravascular to extravascular compartment result in edema & fluid overload.
fluid overload will impair O2 & metabolic diffusion , obstruction of capillary blood flow & lymphatic drainage leading to progressive organ dysfunction.
In addition fluid overload can result from please of complement factors, cytokines, prostaglandins & altered organ microcirculation.
Fluid overload outcomes:
Fluid overload associated with increased mortality in ICU patients.
Volume overload associated with poor respiratory outcome (pulmonary edema, ARDS).
Fluid overload assessment:
History & clinical examination
CXR
BNP level
bio-impendence vector analysis.
Thoracic US
IVC diameters
Fluid overload management:
Diuretics
Extra-corporal therapies.
Aquadex FlexFlow system
Level of evidence is 5
Hussein Bagha baghahussein@yahoo.com
2 years ago
Background
Patients with acute kidney injury, in critical ill conditions, have been frequently found to experience fluid overload. This is often a consequence of resuscitation or severe acute kidney injury (AKI). It is also related to adverse outcomes. Observational studies have shown a link between fluid overload and mortality. Acute respiratory distress syndrome and post-operative states require restrictive fluid management, because it reduces the length of mechanical ventilation and the incidence of cardiopulmonary complications. Fluid overload leads to pulmonary and peripheral edema. The review focused on evaluation and management of fluid overload in the intensive care unit (ICU).
Discussion The role of fluid therapy in the development of fluid overload
For patients who are critically ill, cardiogenic or septic shock is more prevalent. Therefore, fluid resuscitation is often the management of choice, to restore cardiac output, systemic blood pressure and renal perfusion. This depends on understanding the underlying pathology, evaluating the volume status, selection of the appropriate fluid for administration, and maintain and adjusting it for adequate tissue perfusion.
Critically ill patients benefit from crystalloid solutions initially, but over time, they are prone to the risk of increased capillary leaks, leading to increased extracellular volume and thereby causing edema and fluid overload. This causes impaired oxygenation in the lung tissue, distorted tissue architecture, obstruction of capillary flow and lymphatic drainage. These will eventually lead to organ dysfunction. Sepsis may also cause increased capillary permeability.
Fluid overload and outcomes
Bouchard et al showed that patients with fluid overload of more than 10% of their body weight had significantly more respiratory distress, which required mechanical ventilator support, and increased incidence of sepsis. In the pediatric population, a multicenter prospective study found that the percentage of fluid accumulation at the start of CRRT was significantly lower in the survivors.
Acute pulmonary edema and acute respiratory distress syndrome are the most evident adverse effects of fluid overload. Many studies have proven that the patients with acute lung injury and septic shock, who were resuscitated with conservative fluid management had lower mortality rates.
Fluid overload recognition
Daily fluid balance
Cumulative fluid balance
Fluid overload signs
Fluid accumulation – a positive fluid balance
Percentage of fluid overload adjusted for body weight
%fluid overload = (total fluid in-total fluid out)/admission body weight x 100 Fluid status assessment
History and physical examination
Chest radiography
Signs of fluid overloads include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, Kerley lines
Natriuretic peptide levels
High levels of BNP in fluid overload
Bioimpedance vector analysis
Measures whole body volume and is based on the patterns of the resistance-reactance graph, relating body impedance to body hydration.
Thoracic ultrasound
B-lines suggest thickened interstitial or fluid filled alveoli
Vena cava diameter ultrasound
The normal diameter of the inferior vena cava (IVC) is 1.5 to 2.5cm
In volume depletion, the IVC diameter is <1.5cm
In volume overload, the IVC is >2.5cm Fluid overload management
1.Loop diuretics relieve symptoms and pathophysiologic states of fluid overload in patients with AKI
Diuretics can be administered by bolus or as a continuous infusion
Requires monitoring of electrolytes
Urine output needs to be monitored.
2.Extracorporeal therapies
Continuous renal replacement therapy in critically ill patients results in more hemodynamic stability and better fluid balance control and reduces the risk of cerebral edema
Slow continuous ultrafiltration can also be used
Continuous veno-venous hemofiltration is an alternative to provide continuous fluid, electrolyte and toxic clearance.
Conclusion
Some of the complications of fluid overload include congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown and impaired bowel function. Fluid overload has been associated with increased mortality. Optimal assessment of fluid status is important in early management of the patients, to maintain hemodynamic stability and optimize organ function. Initial therapy is the use of diuretics, but they may not always be ideal due to renal dysfunction. Renal replacement therapies are usually needed for volume management in critically ill patients due to underlying kidney injury.
Level of evidence is Level V as this is a narrative review
Eusha Ansary
2 years ago
Summary:
In critical care units fluid overload frequently found in AKI and related to adverse outcomes, like increased mortality and several complications like pulmonary edema, cardiac failure, delayed wound healing, tissue breakdown, and impaired bowel function. Management of fluid balance becomes a central component of critically ill patients.
Appropriate fluid resuscitation is essential in critically ill patients to restore cardiac output, systemic blood pressure and renal perfusion. For this purpose evaluation of volume status, selection of appropriate solution for volume repletion, and maintenance of tissue perfusion is the priority.
Recent studies have established a correlation between fluid overload and mortality in critically ill patients. Recognition and assessment of fluid overload need accurate documentation of intake and output. Accurate volume status evaluation is essential for appropriate therapy since errors of volume evaluation can result in either in lack of essential treatment or unnecessary fluid administration, and both scenarios are associated with increased mortality.
Loop diuretics remain the treatment option of fluid overload. Fluid overload refractory to medical therapy may requires extracorporeal therapies.
VI. Transplant Renal Vein Thrombosis 1. Please summarise this article Introduction
TRVT is one of the major causes of early graft dysfunction & almost inevitably leads to graft loss.
The prevalence of TRVT is 0.1% – 4.2 % of all TXs; higher in DD than in LD TXs. Causes Donor factors:
·Use of a donor’s RK (short vein & long artery)
·Multiple graft vessels
·Prolonged ischemia time
·Vascular injuries
·Older age of donors(donor hypotension with IRI) Recipient factors:
Extremes of age
Pre-TX dialysis modality; PD more than HD
Perioperative hemodynamic status
Primary renal (e.g. membranous nephropathy) Operative factors:
Rena vein kink
Compression by hematomas or lymphoceles
Anastomotic stenosis
Extension of a DVT
Compression of the renal vein by the renal artery ( contra-lateral TXs-RK into LIF & LK into the RIF). Immunosuppression:
Prothrombotic drugs (Cyclosporine, OKT3, high doses of pulsed methyl prednisolone, & ATG) Clinical features:
Rapid onset of oliguria or anuria
Hematuria
Worsening graft function
Painful swollen graft which may progress to rupture
Chronic vein thrombosis is usually asymptomatic.
PE may complicate TRVT. Diagnosis
1.Highly suspicious clinical presentation
2.Doppler USS:
Allows early detection
Noninvasive
Easily available
Safe in the hands of a trained & skilled operator Duplex USS features of TRVT:
a.Reversed arterial diastolic flow (arterial wave form +ve during systole & -ve during diastole)
b.A spike-like systolic component
c.Non-visualization of the renal vein. Typical shapes of reversed diastolic waveforms:
i- type 1 or “transient” waveform (the reversed diastolic waveform returns to baseline before end
Diastole)
ii- type 2 or “plateau” waveform (a flat reversed flow remains constant throughout diastole)
iii- type 3 or “inverted M” waveform (reversed flow throughout diastole has mid-diastolic deceleration).
Differential diagnosis of isolated reversed or absent diastolic arterial:
i- Severe AR
ii- Severe ATN
iii-Hematoma
iv-Vascular kink
TRVT remains an uncommon cause of reversed diastolic flow.
3. MRI
Magnetic resonance angiography is increasingly being reliably used.
Limitations:
Inability to image patients with pace makers
Greater cost
Lack of portability
Prolonged examination time (not suitable in the critically ill) Management
A. Thrombolytic therapy:
Suitable for TRVT in late TX period
Risk of life-threatening hemorrhage.
B. Surgical thrombectomy:
TRVT in the early post-TX.
Risks of anesthesia & post-op infection in an immunosuppressed state.
C. Combined percutaneous mechanical thrombectomy & localized catheter-directed thrombolysis: safe & effective Prevention
Meticulous surgical techniques
Sufficient training in the techniques of anastomosis
Ipsilateral TX (R to R & left to left) whenever possible.
Attention to intravascular volume status (TE Doppler more accurate than CVP)
Meticulous clinical assessment & duplex USS monitoring early post-TX & timely intervention.
Low-dose aspirin & LMWH may benefits in preventing TRVT in high-risk patients. ///////////////////////////// 4. What is the level of evidence provided by this article? Level V
Fluid overload is frequently found in critically ill patients, it has significant adverse outcomes and increases the mortality; hence, manage and optimization of fluid balance becomes a central component of the management of critically ill patients.
The role of fluid therapy in the development of fluid overload
– Adequate fluid resuscitation is essential to the restoration of volume.
– Achieving an appropriate level of volume management requires knowledge of the underlying pathophysiology, evaluation of volume status, selection of appropriate solution.
– Critically ill patients have an increased capillary leak intravenous leading to edema and to fluid overload that result in progressive organ dysfunction.
Fluid overload and outcomes
Several observational studies have demonstrated a correlation between fluid overload and mortality in critically
ill patients with ARDS, ALI, sepsis, and AKI and reduced renal recovery.
Fluid overload recognition and assessment: -Accurate documentation of intakes and outputs; by using one of the following: daily fluid balance, cumulative fluid balance, fluid overload , fluid accumulation, percentage of fluid overload adjusted for body weight.
– History and physical examination: Sings like rales, edema, and elevated JVP. The combination of these signs had a sensitivity of 58 % and specificity of 100 %
-Chest radiography finding include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary
artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines. However, up to
20 % of patients had negative chest radiographs, especially in late-stage heart failure. Technique and severty of overload contribute to detecting finding. -Natriuretic peptides
low BNP levels have a high NPV for excluding heart failure diagnosis
High levels of BNP nonspecific for volume overload, can be high in other cardiac condition. Therefore, we have to take in account the baseline BNP level.
– Bioimpedance vector analysis BIVA
Commonly used method for estimating body composition, specifically detecting soft tissue hydration.
The agreement between BIVA and CVP indications is good, combining BIVA and CVP could provide a
useful tool in the planning of fluid therapy.
– Thoracic ultrasound; B-lines that suggestthickened interstitial or fluid-filled alveoli can be
PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines
Vena cava diameter ultrasound
Normal diameter of IVC is 1.5 to 2.5 cm; volume depletion is considered with an IVC diameter <1.5 cm while an
IVC diameter >2.5 cm suggests volume overload.
Fluid overload management Diuretic therapy
Loop diuretics, remain a valid therapeutic alternative for relieving symptoms of overload.
Some authors advocate that diuretic infusion is superior to boluses since urinary output could be maintain easily
it is important to monitor electrolytes levels and also to assess acid-based status during therapy.
A recent comprehensive review have shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide.
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as CRRT since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
The optimal RRT for patients with AKI and fluid overload has not been defined yet and there is still an ongoing debate. The choice based on the availability, expertise; the individual needs and hemodynamic status.
Conclusion:
Fluid overload has also been related to increased mortality.
The optimal assessment of volume status in critically ill patients is of vital importance.
Meticulous monitoring of fluid balance is critical for all patients
One key aspect of fluid overload management is to maintain hemodynamic stability and optimize organ function
I liked reading your summary and analysis, Will you change your practice based on this article? Ajay
Mohammed Abdallah
2 years ago
Summarise this article
Introduction
Fluid overload is common in AKI patients in the CCU and is associated with adverse outcomes
Aim of the study: evaluation and management of fluid overload in the ICU
Discussion
The role of fluid therapy in the development of fluid overload
Appropriate fluid management requires knowledge of the pathophysiology, evaluation of volume status, selection of appropriate solution, and maintenance and modulation of the tissue perfusion
Consequences of fluid overload in organ systems are cerebral edema, myocardial edema, pulmonary edema, renal interstitial edema, hepatic congestion, gut edema, and tissue edema
Fluid overload and outcomes
There is a correlation between fluid overload and mortality in critically ill patients with ARDS, acute lung injury, sepsis, and AKI according to several studies
Fluid overload recognition and assessment
1. Daily fluid balance
2. Cumulative fluid balance
3. Fluid overload (pulmonary edema or peripheral edema)
4. Fluid accumulation
5. Percentage of fluid overload adjusted for body weight (A cutoff of ≥10 % has been associated with increased mortality)
% Fluid overload = ((total fluid in−total fluid out) /admission body weight * 100)
Fluid status assessment History and physical examination
Chest x ray
Natriuretic peptideshigh levels of BNP (can be elevated in MI and PE). Has a high negative predictive value
Electrolyte disturbances are common and need monitoring assessment of acid base balance
In patients with AKI the response to furosemide may be reduced due to reduced tubular secretion of furosemide and blunted response of Na-K-2Cl co-transporters at the loop of Henle (higher doses are needed with the risk of ototoxicity and myocardial dysfunction)
Extracorporeal therapies
In fluid overload refractory to medical therapy (CRRT/SCUF)
Conclusions
Fluid overload is associated with complications (CHF, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function) and increase mortality
It is important to assess the volume status early in critically ill patient
Loop diuretics are used to treat fluid overload in critically ill patients with fluid overload but diuretic resistance developed particularly in AKI
I liked reading your summary and analysis, Will you change your practice based on this article? Ajay
Doaa Elwasly
2 years ago
-Background
Multiple studies empathised the association between fluid overload and mortality specially in critically ill patients.
Restrictive fluid therapy is suitable in ARDS and after major surgeries because it can decrease the duration of mechanical ventilation and the rate of cardiopulmonary complications .
Volume status evaluation is crucial particularly in critically ill patients . Discussion Fluid therapy role in the development of fluid Overload
Achieving appropriate fluid therapy in critically ill patients is crucial meanwhile this achievement necessitate proper evaluation of the patient volume status, suitable solution for volume repletion, and maintenance of tissue perfusion.
The use of crystalloid as an initial therapy in patients at risk of AKI and with sepsis can increase the fluid overload incidence leading to impairment of tissue oxygenation and organ dysfunction. Fluid overload and outcomes
Bouchard et al. mentioned that patients with fluid overload occurring with more than 10% increase in body weight is accompanied by higher incidence of respiratory failure , mechanical ventilation and sepsis .
AKI cases having fluid overload has high 30 and 60 day mortality also their renal recovery is much lower.
Multiple studies conducted on adults and paediatrics stated that accumulation of fluid detected on starting CCRT therapy was much lower in cases who survived.
Fluid overload can lead to pulmonary oedema or ARDS ,a study declared that cases with septic shock and ALI had lower hospitalisation mortality with conservative fluid therapy.
VASST study published that fluid overload therapy specially those with CVP> 12 mmHg are associated with increased mortality. Fluid overload detection and evaluation
There is no standardization for documentation of intake and output, that is why it is highly variable therefore not reliable enough.
Suggestions were proposed to achieve standardization
including daily fluid balance excluding insensible water loss, cumulative fluid balance,fluid overload, fluid accumulation with or without fluid overload ,fluid overload % adjusted for body weight.
Most of methods used to evaluate fluid status are inaccurate involving
– History and physical signs of fluid overload in addition to basic investigations as chest xray which has a poor predictive value of volume overload , ECG ,BNP which seemed to be the most beneficial test as if it is high can correlate with volume overload but harbours falses as well because BNP level can increase with RF and decrease with obesity , low levels have higher negative predictive values and not higher levels.
– Bioimpedance vector analysis (BIVA) detects whole
body fluid volume and is dependent on patterns of the resistance-reactance graph, relating body impedance to body hydration
BIVA and CVP was compared in a study and concluded that both were in accordance with each other in the high CVP group(13-20 mmHg), moderate accordance in the medium CVP(4-12mmHg)group, and poor in low CVP group(0-3 mmHg).
Therefore combing both BIVA and CVP can represent a useful diagnostic tool for deciding for the fluid therapy specialy in cases with low CVP.
-Thoracic US
Agricola et al declared that PCWP correlated with the B-lines “comet-tail images”detected by thoracic US in patients with congestive heart failure.
-IVC diameter US
IVC diameter <1.5 cm can be indicative of volume depletion while an IVC diameter >2.5 cm indicates volume overload.
Lyon et al demonstrated appreciable difference between the IVCde before and after blood donation and between IVCdi before and after donation .
IVC d and right ventricule diameter assessment could be a non invasive method for evaluation of the fluid status and the response to fluid therapy in critically ill cases. Treatment of fluid overload Diuretics
Ultrafiltration is not superior till now on diuretics in treatment of overloaded cases with or without AKI regarding the AKI progression and overall outcomes.
Aggressive diuretic use can decrease fluid overload and outcome but at the same time carrier a risk of AKI.
A target of t a urine output of 3–4 ml/kg/h was suggested as it rarely causes hypovolemia.
A study demonstrated that diuretic infusion can be better as it can achieve better diuresis with higher urinary output meanwhile using smaller doses therefore avoiding the side effects.
On the other hand DOSE-AHF study stated that AHF cases can need bolus doses.
The treatment method either bolus of infusion is debatable.
Electrolyte monitoring is important due to high risk of electrolyte disturbance as hypokalaemia ,hypomagnesemia and hypochloremic metabolic alkalosis that need correction.
Torsemide and bumetanide were introduced as having better pharmacokinetic profiles than furosemide, but their effects are conflicting.
Higher doses of frusemide are needed in AKI due to the reduced response to frusemide ,leading to higher risk of side effects as ototoxicity and myocardial dysfunction. Extracorporeal therapy
It is needed in refractory cases to medical therapy in critically ill patients with hemodynamic instability and organ dysfunction.
CRRT advantage over intermittent hemodialysis is that it removes the fluid slowly preserving hemodynamic stability as well as slow control of solute concentration avoiding cerebral oedema due to fluid shift.
Studies suggested that CRRT is an independent predictor of renal recovery among the surviving cases.
In critically ill patients with AKI and volume overload the use of CRRT or IHD depends on the patient needs and hemodynamic status.
SCUF is a type of CRRT done with low blood flow rates and low ultrafiltration rates.
CVVH provides continuous fluid ,electrolytes and toxin clearance.
The aim is preserving tissue perfusion, maximizing fluid balance by removal of fluid without decreasing the effective circulating volume, therefore, precise monitoring of fluid balance is mandatory .
Costanzo et al. found that patient treated with ultrafiltration experienced a longer time to recurrence of heart failure
, and fewer heart fail[1]ure and cardiovascular events.
Compared to cases treated with intravenous loop diuretics. Conclusion
Fluid overload is associated with many complications as heart failure and even mortality.
Therefore assessment of fluid status is mandatory specially in critically ill cases.
The aim of fluid therapy is to preserve hemodynamic stability and organ functions.
Loop diuretic effectiveness is limited
RRT can be needed in management of fluid overload in critically ill patients.
I liked reading your summary and analysis, Will you change your practice based on this article? Ajay
Mahmoud Wadi
2 years ago
VI. Fluid overload in the ICU – evaluation and management
Summarise this article
What is the evidence provided by this article
——————————————————————————————————————-
Fluid overload is frequently found in acute kidney injury patients in critical care units.
The relationship of fluid overload with adverse outcomes; hence, manage and optimization of fluid balance becomes a central component of the management of critically ill patients.
Restrictive fluid management are beneficial during acute respiratory distress syndrome and following major surgery since they reduce the duration of mechanical ventilation and the rate of cardiopulmonary complications.
Discussion
The role of fluid therapy in the development of fluid overload
Adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or septic shock.
Adequate crystalloids solutions are recommend for the initial management of patients with or at risk of AKI and also in patients with sepsis expands the extracellular compartment, but over time since critically ill patients have a increased capillary leak intravenous solutions will leave the circulation and dis- tribute in the extracellular volume leading to edema andto fluid overload.
These effects are prominent in encapsulated organs (liver and kidneys).
Fluid overload and outcomes
patients with fluid overload defined as an increase in body weight of over 10 % had significantly more respiratory failure, need of mechanical ventilation, and more sepsis.
AKI patients with fluid overload had increased 30 day and 60 day mortality.
Among survivors, AKI patients who required RRT had a significantly lower level of fluid accumulation at initiation of dialysis and at dialysis cessation than non-survivors.
Renal recovery was significantly lower in patients with fluid overload .
Lungs are one of the organs in which adverse effects of fluid overload are most evident, acute pulmonary edema or acute respiratory distress syndrome.
In one of these studies, septic shock patients with acute lung injury who received conservative fluid management after initial fluid resuscitation had lower in-hospital mortality.
Patients randomized with conservative fluid had lower cumulative fluid balance, improved oxygenation index and lung injury score, increased number of ventilator-free days, and reduction in the length of ICU stay.
Vasopressin in Septic Shock Trial (VASST) study authors found that higher positive fluid balance correlated significantly with increased mortality with the highest mortality rate observed in those with central venous pressure >12 mmHg.
Fluid overload recognition and assessmen
Daily fluid balance
Cumulative fluid balance: sum of each day fluid.
Fluid overload
Fluid accumulation
Percentage of fluid overload adjusted for body weight
-Fluid overload percentage can be calculated using the following formula : % Fluid overload ¼ total fluid in−total fluid out / addmmesiom body weight X 100
Fluid status assessment
Most of the tests currently used are fairly inaccurate
History and physical examination:
The usefulness of medical history, symptoms, and signs along with routine diagnostic studies (chest radiograph, electrocardiogram, and serum B-type natriuretic peptide (BNP)) that differentiate heart failure from other causes of dyspnea in the emergency department .
Chest radiography
Chest x-ray has been one of the most used tests to evaluate for hypervolemia( include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominentsuperior vena cava, and Kerley lines).
Up to 20 % of patients diagnosed with heart failure had negative chest radiographs at initial emergency department evaluation.
Natriuretic peptides
High levels of BNP can be found with volume overloadOn the other hand, high BNP levels can be nonspecific for volume overload .
Some conditions like myocardial infraction and pulmonary embolism can cause elevated levels of BNP.
Other conditions evaluating BNP levels are obesity, associated with lower BNP levels and renal failure, associated with high BNP levels.
Patients with heart failure who have elevated base-line levels of BNP.
The greatest utility of BNP levels is in the absence of elevation, since low BNP levels have a high negative predictive value for excluding heart failure diagnosis.
Bioimpedence vector analysis
Estimate body composition and soft tissue hydration, noninvasive and inexpensive.
Combined BIVA and CVP may improve clinical assessment and fluid therapy management.
Thoracic ultrasound
Sonographic artifacts as B-lines suggest fluid filled alveoli and thickened interstitial.
Vena cava diameter Ultrasound
Inferior vena cava diameter and right ventricle diameter are practical and noninvasive, used in fluid state estimation.
Fluid overload management
Diuretic therapy:
The safe and goal of urine out puy that is not associated with intravascular volume depletions is 3–4 ml/kg/h
Diuretics use is occasionally associated with increased in the serum creatininebut the overall outcome is good.
Diuretic infusion may be preferred than bolus as it is easily tailored and can provide the same uop with lower doses than when using bolus therapy
Close observation of electrolytes (hypokalemia, hypomagnesimia) and acid base disturbances (metabolic alkalosis)
Hypokalemia can be treated either by giving potassium or adding spironolactone
Higher doses are associated with increase in the risk of ototoxicity, especially in patients with AKI.
Extracorporeal therapies
The optimal RRT for patients with AKI and fluid overload has not been defined yet and there is still an ongoing debate.
In patients with fluid overload, CRRT provides a slower fluid removal over intermittent hemodialysis (IHD) resulting in more hemodynamic stability and better fluid balance control.
–Other advantages of CRRT over IHD include:-
a slower control of solute concentration avoiding large fluctuations and fluid shifts, which reduce the risk of cerebral edema, the great flexibility in terms of treatment adjustment to patient’s needs at anytime.
CRRT allows to perform the treatment with relatively simple and user friendly machines .
Conclusions
Fluid overload has also been related to increased mortality.
The optimal assessment of volume status in critically ill patients is of vital importance particularly during the early management of these patients.
Loop diuretics are frequently used as the initial therapy to treat critically ill patients with fluid overload; nevertheless, and have limited effectiveness due to several factors such as underlying AKI that contribute to diuretic resistance.
RRT are often required for optimal volume management in critically ill patients with fluid overload.
Fluid overload treatment with ultrafiltration,and clear treatment goals.
Introduction
One of the most important aspects of care in ICU is fluid management as this has a major role to play on how long a patient will remain on ventilator or even the outcome of the care. Recovery has been seen to be better and faster among patient with AKI but not fluid congested compared to those that are overload with fluid
Fluid overload and outcome
several observational studies have reported a relationship between fluid overloads among patient with ARDS, acute lung injury, AKI, and critically ill
fluid overload patient has increase 30 to 60 days mortality
Among AKI patients, those with fluid overload has reduced survival rate compared to those that were not fluid overloaded
Assessment of fluid status
history and physical examination
chest radiography
natriuretic peptides
bioimpedance vector
thoracic Ultrasound
vena cava diameter ultrasound
Fluid overload management
diuretic therapy
extracorporeal therapy
-CRRT – preferred
-IHD – not the idea for critically ill patient
Conclusion
Alot of severe complications including mortality has been attributed to fluid overload, hence optimal fluid management is key to survival of critically ill patient
Fluid overload is commonly found in critically ill patients with AKI, it is associated with several adverse effects as peripheral edema, pulmonary edema and delayed wound healing. The role of fluid therapy in development of fluid overload:
Adequate fluid resuscitation is essential in patients with septic and cardiogenic shock, initially, crystalloids are administered then distributed to extracellular volume due to increased capillary leak leading to fluid overload, impaired cell to cell interaction and progressive organ dysfunction especially kidney and liver.
Also, fluid overload occurs due to severe sepsis due to altered microcirculation. Fluid overload and outcome:
Several studies suggested an association between fluid overload and mortality in critically ill patients, fluid overload was associated with difficulty in weaning from mechanical ventilation and more sepsis while conservative fluid management resulted in lower hospital mortality, improved oxygenation and shorter hospital stay
The VASST trial showed higher mortality rates in patients with fluid overload. Fluid overload recognition and assessment:
Includes daily fluid balance, cumulative balance, fluid overload, fluid accumulation and percentage of fluid overload adjusted for body weight. Fluid status assessment:
Most of tests are considered inaccurate. History and physical examination:
History of heart failure and PNDs, signs as lower limb edema, jugular venous pressure.
Have variable sensitivity and specificities and should be combined with other measures. Chest radiography:
Chest X-ray commonly used with limitations as absent signs of pulmonary congestion in some patients at time of diagnosis, portable X-ray have reduced sensitivity in supine patients. Natriuretic peptide:
Increase in volume overload, MI and pulmonary embolism, may be lowered in obesity and may be increased in renal failure
Low BNP has negative predictive value for excluding heart failure. Bioimpedence vector analysis:
Estimate body composition and soft tissue hydration, noninvasive and inexpensive.
Combined BIVA and CVP may improve clinical assessment and fluid therapy management. Thoracic U/S:
Sonographic artifacts as B-lines suggest fluid filled alveoli and thickened interstitial Vena cava diameter U/S:
IVC diameter and right ventricle diameter are practical and noninvasive, used in fluid state estimation. Fluid overload management: Diuretic therapy:
Alternative to ultrafiltration in AKI and congestive heart failure, no evidence suggesting better outcome with ultrafiltration than with diuretic therapy.
Although diuretic may increase risk of AKI, they are associated with more volume removal and better outcome.
Given as bolus or continuous infusion, infusion is associated with more response and less adverse effects in some studies.
May lead to hypokalemia, hypomagnesemia and hypochloremic metabolic alkalosis.
Torsemide and bumetanide are more favorable than frusemide. Extracorporeal therapy:
used in fluid overload resistant to diuretic therapy, the optimal RRT in patients with AKI and overload is not well determined.
Modality is determined by available resources, local expertise and hemodynamic state.
CRRT maintain hemodynamic stability, better fluid balance control and avoid large fluid shift
CRRT and IHD can be used as complementary therapy according to hemodynamics.
Slow continuous ultrafiltration and continuous veno-enous hemofiltration are other types of CRRT.
The goal is to maintain tissue perfusion and removing fluid without affecting circulating fluid volume.
Aquadex FlexFlow system is a new small portable device for treatment of fluid overload.
Volume overload in critically ill patients is associated with higher incidence of mortality and complications including heart failure, pulmonary edema, delayed wound healing, GIT function impairment,
It was reported that in critically ill patients a 10 % increase in weight due to volume overload is associated with increase in the risk of respiratory distress, mechanical ventilation and mortality after 30 and 60 days
The use of IV fluids is represents an important cause of volume overloads and thus restrictive fluid management strategies are usually advised
Large proportion of crystalloids infused are distributed in the extravascular space with subsequent impairment of the diffusion of oxygen and metabolites and obstruction of capillary and lymphatic drainage of the tissues
The accurate assessment of volume status will help to minimize the gap between volume overload (associated with high mortality) and volume depletion (associated with organ hypoperfusion and AKI) and will also decrease the need for CRRT
Assessment of fluid status
A- History
Including history of heart failure for example, PND
B-Clinical assessment
Assessment of vital signs (MAP, HR), neck veins ( 80% sensitive and specific), chest (pulmonary congestion) , heart (gallop) and LL edema
CVP measurement
Fluid balance status (daily and cumulative) and determine if the patient has positive or negative fluid balance, but we should beware of the insensible losses
Assessment of body weight preadmission and daily thereafter
Calculation of the percentage of fluid overload by dividing cumultative fluid balance (total input-total output) by the preadmission weight X100 and putting a cutoff of > 10 as a marker for bad outcome
C- Laboratory investigations
proBNP (has negative predictive value if < 100 pg/mL), but false high levels can be seen in MI, pulmonary embolism, old age, renal failure
Blood gasses, as metabolic alkalosis can denotes volume depletion
Central VBG O2 saturation
D- Radiological investigations
CXR (signs of overload includes cardiomegaly, pleural effusion, Kerley lines, dilated upper lobe vessels, interstitial and alveolar edema) sensitivity and specificity of CXR is not high especially in mechanically ventilated patients
Thoracic ultrasound for detection of B lines that is associated with thickened interstitial or fluid-filled alveoli
Abdominal ultrasound with assessment of IVC diameter 3 cm from the atrium in relation to respiration ( respiratory variation), normally it is 1.5 to 2.5 cm, < 1.5 cm is associated with volume depletion while> 2.5 cm is associated with volume overload.
E- Cardiac assessment
ECG (which may detect AF)
ECHO
Pulmonary capillary wedge pressures
F- Bioimpedance vector analysis
It is a method that asses the total body fluids, it is noninvasive, inexpensive and accurate
Management of fluid overload
Diuretics
The safe goal of UOP that is not associated with intravascular volume depletions is 3–4 ml/kg/h
Diuretics use is occasionally associated with increased in the serum creatinine but the overall outcome is good
Diuretic infusion may be preferred than bolus as it is easily tailored and can provide the same uop with lower doses than when using bolus therapy
Close observation of electrolytes (hypokalemia, hypomagnesimia) and acid base disturbances (metabolic alkalosis)
Hypokalemia can be treated either by giving potassium or adding spironolactone
Higher doses are associated with increase in the risk of ototoxicity, especially in patients with AKI
Extracorporeal therapies
CRRT is preferred to IHD in critically ill patients especially in the setting of hemodynamic instability and sepsis
Indicated in patients with volume overload refractory to medical therapy or patient with AKI
Modalities most commonly used in CRRT are SCUF, SLED, CVVHF, CVVHDF
This article has a central theme of evaluating and managing appropriately fluid overload in the ICU.
The occurrence of fluid overload in critically ill patients is significant because it can lead to pulmonary edema, cardiac failure, delayed wound healing, tissue breakdown, and impaired bowel function. This article focusses on understanding the background behind fluid overload and how fluid therapy can be sustainably maintained to avoid complications in the patient.
Fluid resuscitation is important to maintain good cardiac output, systemic BP and renal perfusion. However, with constant administration of crystalloid solutions as part of initial treatment for AKI patients, there can develop a leakage of IV fluids into the extravascular space, causing edema and fluid overload. Edema can occur from increased capillary permeability proteins, as well as increased hydrostatic pressure because of reduced pre capillary vasoconstriction.
This has several harmful effects like
impaired oxygen and metabolite diffusion
distortion of tissue architecture
obstruction of capillary flow
obstruction of lymphatic drainage
disturbance in cell to cell interactions
progressive organ dysfunction
Liver, lungs and kidneys are affected to the maximum from these effects. Renal recovery is lower in patients with fluid overload.
Fluid overload recognition and assessment needs recording of daily fluid balance, cumulative fluid balance, fluid overload, fluid accumulation, and percentage of fluid overload adjusted for body.
In terms of investigation,
chest X ray can be used for hypervolemia assessment. The signs seen are dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent vena cava and Kerley lines.
high levels of BNP is seen with volume overload. Differentials for this include myocardial infarction and pulmonary embolism. Renal failure also appears on this list.
Bioimpedance vector analysis is used to estimate body composition in order to detect soft tissue hydration with minimal error.
Thoracic ultrasound detects thickened interstitial or fluid filled alveoli.
Vena cava diameter ultrasound can detect volume depletion or volume overload. Normal IVC diameter is 1.5 to 2.5 cm. This diameter reduces to less than 1.5 cm, and increases above 2.5 cm for volume overload.
Treatment options include
Diuretic therapy such as loop diuretics. However, it is to be noted that AKI patients have reduced response to furosemide, and the use of higher doses as a result can cause ototoxicity or even myocardial dysfunction.
Extracorporeal therapies are used for patients whose fluid overload is unresponsive to medical therapy. Continuous renal replacement therapies might be needed. The optimal treatment option has not been defined yet. CRRT and intermittent hemodialysis are options possible. Continuous vent venous hemofiltration allows meticulous control of fluid balance by giving continuous fluid, electrolyte, and toxin clearance.
Ultimate goal is preserving tissue perfusion.
Level of evidence
This is a narrative review, hence level of evidence is 5.
Background
Fluid overload is frequently found in critically ill patients with AKI.
Its associated with increase mortality.
Consequences of fluid overload in organ systems:
Organ consequences.
Consequences Cerebral edema Impaired cognition Delirium
Myocardial edema Conduction disturbance Impaired contractility Diastolic dysfunction
Pulmonary edema Impaired gas exchange Reduced compliance Increased work of breathing
Renal interstitial edema. Reduced RBF Increased interstitial pressure, Reduced GFR ,Uremia
Hepatic edema Impaired synthetic function, Cholestasis
Gut edema Malabsorption , Ileus .
Tissue edema Poor wound healing Wound infection Pressure ulceration
Discussion :
The role of fluid therapy in the development of fluid overload :
In critically ill patients, adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or sepsis.
but over time since critically ill patients have a increased capillary leak intravenous solutions will leave the circulation and distribute in the extracellular volume leading to edema and to fluid overload.
These results in impaired oxygen and metabolite diffusion, distorted tissue architecture, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may then contribute to progressive organ dysfunction.
overload and outcomes:
There’s a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
patients with fluid overload defined as an increase in body weight of over 10 % had significantly more respiratory failure, need of mechanical ventilation, and more sepsis.
AKI patients with fluid overload had increased 30 day and 60 day mortality.
Among survivors, AKI patients who required renal replacement therapy had a significantly lower level of fluid accumulation at initiation of dialysis and at dialysis cessation than non-survivors.
Renal recovery was significantly lower in patients with fluid overload
Fluid status assessment :
Accurate volume status evaluation is essential for appropriate therapy .
History. And physical examination.
I.e history of CHF or symptoms of heart failure, SOB,PND,
Presence. Of raised JVP, peripheral edema, rales (low sensitivity).gallop rhythm.
Investigation:
CXR ,sign of fluid overload .
BNP :high negative predictive value when low ,high in fluid overload ,heart failure MI,PE,RF.
Bioimpedance vector analysis:
Bioelectrical impedance analysis is a commonly used method for estimating body composition, specifically detecting soft tissue hydration with a 2–3 % measurement error. It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
Thoracic ultrasound :
Sonographic artifacts known as B-lines that suggest thickened interstitial or fluid-filled alveoli can be detected using thoracic ultrasound.
Vena cava diameter ultrasound :
The measurement of the inferior vena cava (IVC) diameter can also be use to assess volume status. Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Management. Of fluids overload:
Diuretic
Extracorporeal therapies :
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
Conclusions :
Several complications like congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function are associated with fluid overload. Fluid overload has also been related to increased mortality. The optimal assessment of volume status in critically ill patients is of vital importance particularly during the early management of these patient.
Level of evidence V.
Fluid overload is associated with multiple fatal problems could be iatrogenic in ICU setting due to high volume of crystalloid infusion
Diagnosis:
Symptoms and examination
I/O balance daily and cumulative balance
CXR
BNP
it can cause pulmonary edema ,congestive heart failure,myocardial edema ,bowel and hepatic congestion ,cerebral edema
% of fluid overload adjusted for body weight if>/= 10% ,ass with high mortality
calculated using this formula:
% Fluid overload= ((total fluid in-total fluid out)/ admission body weight × 100)
management:
Diuretics:Furosemide:high doses can cause myocardial ischemia,
in case of resistance:add thiazides
if no response start CRRT
Fluid overload is associated with adverse outcome in critically ill patients in ICU. Although adequate fluid therapy is necessary for proper cardiac outcome, systematic BP, renal perfusion and prevention of AKI, but capillary leak may lead to edema formation. Fluid overload results in impaired oxygen delivery, disturbed cell to cell interactions and may lead to organ dysfunction such as cerebral edema, myocardial edema, pulmonary edema, hepatic and gut congestion and reduced RBF or GFR.
Fluid overload and outcome:
Fluid overload more than 10% is associated with increased respiratory failure, ARDS, sepsis, AKI and higher mortality.
Fluid overload recognition and assessment:
This requires an accurate calculation of intakes and outputs. Useful definitions include:
1- Daily fluid balance.
2- Cumulative fluid balance: sum of daily fluid balance during a period of time.
3- Fluid overload: indicates a degree of peripheral edema or pulmonary edema.
4- Fluid accumulation: positive fluid balance.
5- Percent of fluid overload adjusted for BW: cumulative fluid balance presented as a percent with increased mortality over 10%.
6- %Fluid overload= [(total intake-total output)/admission BW*100]
Fluid status assessment:
1- History and physical examination.
2- CXR
3- Natriuretic peptides
4- Bio-impedance vector analysis.
5- Thoracic ultrasound to define B-lines.
6- Vena cava diameter ultrasound: normal is 1.5-2.5 cm. More than 2.5 cm suggests volume overload
Fluid overload management:
1- Diuretic therapy: especially loop diuretics.
2- Extracorporeal therapies such as CRRT (in form of SCUF or CVVH) or IHD.
Conclusion:
Fluid overload results in increased mortality and complications such as CHF, pulmonary edema, impaired wound healing and bowel function. Loop diuretics have limited effectiveness and RRTs are often required.
The level of evidence is 5.
In critically ill patients, maintaining acheiving blood volume to maintain COP and tissue perfusion is a life saving . AKI complicating critical illness carries poor prognosis specially when complicated with volume overload.Hense it’s extremely important to evaluate volume status and calculate and maintain adequate fluid balance to improve prognosis of critically ill patients.
Fluid therapy aim at acheiving balance between tissue perfusion that will be impaired if low fluid volume is used and avoid hypervolemia that’s commonly complicated with prepheral tissue oedema , pulmonary congestion and delayed weaning from MV,cerebral oedema leading to increase ICT, fits and coma , hepatic congestion impairing liver synthetic function and in sever cases HE or DIC can develop, GIT congestion leading to malabsorption , tissue oedema impair tissue healing and predispose to ulceration
Evaluation of volume overload
1- History: fluid intake , fluid loss ( vomiting , diarrhea)
2- physical examination: signs of hypervolemia include
– Heart: tachycardia , S3 gallop murmer
– Lung : pulmonary congestion or edema manifested as crepitation s and decrease air entery respectively.
Abd : ascites , enlarged tender liver
LL : odema
Investigations
1- chest : CXR , CT , US
all are non invasive and can evaluate volume status.
2- Heart : non invasive investigations as echo
and invasive investigations as pulmonary catheter to evaluate pulmonary capillary wedge pressure.
– pelvi- abd US
– Bioimpedence .
Lap investigations useful for volume status assessment include
1- B natriuretic peptide.
Management of volume overload
1- fluid restriction.
2- Diuretic therapy.
3- Extracorporeal removal of excess fluid
Level of evidence: 5
Fluid overload in the ICU: evaluation and management
Fluid overload recognition and assessment
Accurate documentation of intakes and outputs are required for fluid overload recognition and assessment in critically ill patients.
Useful definitions
1- Daily fluid balance: daily difference in all intakes and all outputs, which frequently does not include insensible losses.
2- Cumulative fluid balance: sum of each day fluid balance over a period of time.
3- Fluid overload: implies a degree of pulmonary edema and peripheral edema.
4- Fluid accumulation: positive fluid balance, with or without linked fluid overload.
5- Percentage of fluid overload adjusted for body weight:
Accumulative fluid balance that is expressed as a percent. A cutoff ≥ 10 % has been associated with increased mortality. Fluid overload percentage can be calculated using the following formula:
% fluid overload
= [(total fluid in – total fluid out)/admission body weight x 100]
Fluid status assessment
There are several methods to evaluate fluid status; However, most of these tests currently used are fairly inaccurate.
· History and physical examination
Medical history, symptoms, and signs along with routine investigations (like CXR, ECG, BNP) use to detect the probability and differentiate heart failure from other causes of dyspnea in the emergency were evaluated by many studies. Importantly, signs like pulmonary rales, lower extremity oedema, and jugular venous distention have significant limits for assessing fluid overload.
· Chest radiography
Most widely used. Radiological signs of fluid overload include dilated upper lobe vessels, cardiomegaly, interstitial oedema, enlarged pulmonary artery, pleural effusion, alveolar oedema, prominent superior vena cava, and Kerley lines. 20% of heart failure patients had negative chest X-ray findings. these findings do not correlate with PCWP. Also, they are affected by the technique and the patient’s status. Portable CXR, reduce the sensitivity of finding fluid overload, and pleural effusion can be missed in the supine position. The presence of X-ray findings increased with the severity of heart failure.
· Natriuretic peptides:
A high level of BNP can be found in fluid overload. Although, there are other conditions that may increase BNP like:
1- MI
2- Pulmonary embolism
3- Obesity
4- CKD
The greatest utility of BNP levels is in the absence of elevation since low BNP levels have a high negative predictive value for excluding heart failure diagnosis. While high BNP levels can be non-specific for volume overload.
· Bioimpedance vector analysis
It is used to detect body composition, specifically detecting soft tissue hydration with a 2–3 % error. Bioimpedance vector analysis (BIVA) measures the whole-body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration. Clinical information is compared with the patterns of healthy populations. A study comparing the BIVA to the CVP; found that The agreement between BIVA and central venous pressure indications was good in the high CVP group, moderate in the medium CVP group, and poor in the low CVP group.
· Thoracic ultrasound:
PCWP and fluid accumulation in the lungs have been correlated with the presence of B-lines (“comet-tail images”) in patients with congestive heart failure. The comet-ail-score was found to correlate with extra-vascular lung water determined by PiCCO system. PCWP, x-ray findings.
· Vena cava diameter ultrasound
IVC diameter was used to assess volume status. The normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); in case of volume depletion an IVC diameter < 1.5 cm. IVC diameter > 2.5 cm suggests volume overload.
IVC diameter and right ventricular diameter evaluation could be a practical noninvasive method for fluid status estimation and response to therapy in critically ill patients.
Fluid overload management
A- Diuretic therapy:
Loop diuretics, remain a valid therapeutic alternative for relieving symptoms and improving fluid overload in congestive heart failure and in patients with AKI. There is no evidence that favors ultrafiltration over diuretic use in volume overload patients with or without AKI. Despite that more patients developed AKI during diuretic treatment, numerous studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes. Some empirical observations have shown that a urine output of 3–4 ml/kg/h rarely causes intravascular volume depletion.
They could be administered by bolus or continuous infusion. There has been controversy about which strategies is better.
It is important to assess acid-base status and electrolyte levels as the diuretics used are associated with electrolyte disturbances.
v Hypokalemia can be avoided with oral potassium or the use of spironolactone.
v Hypomagnesemia is frequently found during diuretic therapy, magnesium replacement can be achieved either orally or IV, with 20 – 30 mmol per day.
v chloride losses exceed sodium losses and hypochloremic metabolic alkalosis develops; this is usually corrected with the administration of potassium chloride and magnesium chloride.
Torsemide it could be more efficacious than furosemide in patients with heart failure (decreased mortality, hospitalization and, NYHA class).
In AKI patients, as compared with torsemide the use of furosemide was associated with a significant improvement in urine output.
In AKI, the response to furosemide may be reduced by:
1- reduced tubular secretion of furosemide.
2- Blunted response of Na-K-2Cl co-transporters at the loop of Henle.
This requires higher doses of furosemide that may increase the risk of ototoxicity and can cause myocardial dysfunction secondary to vasoconstriction caused by furosemide.
B- Extracorporeal therapies
Refractory medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies. Management of fluid balance is obligatory with the goal to improve pulmonary gas exchange and organ perfusion while maintaining stable hemodynamic parameters. The optimal RRT modality has not been yet defined. CRRT has advantages over IHD. The choice of modality depends on the patient’s status, availability, and staff experience.
CRRT is an independent predictor of renal recovery among survivors. Slow continuous ultrafiltration (SCUF) is usually performed with a low blood flow rate (50 to 100 ml/min) and ultrafiltration between 100 and 300 ml/h according to fluid balance necessities. CVVH is another modality of CRRT which allows continuous fluid, electrolyte, and toxin clearance.
Another option for treating patients with fluid overload is the new smaller and more portable devices like the Aquadex FlexFlow System (Baxter Healthcare) however, yet associated with an adverse effects of special interest and a serious study product-related adverse events
Conclusion:
Fluid overload is associated with increased mortality. The principal aspect of fluid management is to maintain hemodynamic stability and organ perfusion. Loop diuretics play an important role in fluid overload management, but their effect may be blunt in advanced AKI. Continuous renal replacement therapy with different modalities can be used to provide controlled fluid overload management.
level V
Fluid overload in critically ill patient is associated with adverse outcome as impaired O2 delivery, organ dysfunction as cerebral edema and pulmonary edema
Fluid overload is associated with increase in mortality.
Can be assessed by:
clinically
chest X-ray
Natriuertic peptides
Chest USG
Ultrasound to assess Inferior vena cava diameter normally 1.5 to 2.5 cm more than 2.5 indicates volume overload
Managed by :
Diuretics
Extracorporeal Therapy as dialysis or CRRT
recent studies have highlighted the role of fluid overload on adverse outcomes
Restrictive fluid management strategies are beneficial during ARDS and following major surgery
The administration of crystalloids solutions expands the extracellular compartment, but over time due to capillary leak, intravenous solutions distribute in the extracellular volume leading to edema and to fluid overload.
These results in
1. impaired oxygen
2. Impaired metabolite diffusion,
3. distorted tissue architecture,
4. obstruction of capillary blood flow and lymphatic drainage,
5. disturbed cell to cell interactions
6. then contributed to progressive organ dysfunction
Edema is attributed to a combination of
Fluid overload and outcomes
Bouchard et al., have shown that patients with fluid overload (increase in body weight of over 10 %) had significantly
Renal recovery was significantly lower in patients with fluid overload
In children, a multicenter prospective study found that the percentage of fluid accumulation at initiation of CRRT was significantly lower in the survivors (14.2 % ±15.9 % vs. 25.4 % ±32.9 %, P=0.03)
.Several studies have provided evidence associating positive fluid balances with poorer respiratory outcomes.
In one of these studies, septic shock patients with acute lung injury who received conservative fluid management after initial fluid resuscitation had lower in-hospital mortality
In another study, Wiedemann et al. randomized 1000 patients to either a conservative or to a liberal strategy of fluid management. Patients with conservative fluid strategy had:
• lower cumulative fluid balance,
• improved oxygenation index and lung injury score,
• increased number of ventilator-free days,
• reduction in the length of ICU stay.
• did not increase the incidence or prevalence of shock during the study
• did not increase the need for renal replacement therapies
Fluid overload recognition and assessment
. Mehta RL and Bouchard J proposed some useful definitions
1. Daily fluid balance:
2. Cumulative fluid balance
3. Fluid overload
4. Fluid accumulation:
5. Percentage of fluid overload adjusted for body weight:
A cutoff of ≥10 % has been associated with increased mortality.
. Fluid status assessment
1- History and clinical examination
along with routine diagnostic studies (chest radiograph, ECG, and serum(BNP)) were evaluated in a meta-analysis.
Butman et al. found that the presence of jugular venous distension, at rest or inducible, had a sensitivity (81 %), and a specificity (80 %) for elevation of the pulmonary capillary wedge pressure (≥18 mmHg).
Using hepato-jugular reflux and Valsalva maneuvers, Marantz et al. showed that these maneuvers were valid in the diagnosis of congestive heart failure in acutely dyspneic patients, with low a sensitivity (24 %) and a high specificity (94 %)
2- Chest radiography
1. dilated upper lobe vessels,
2. cardiomegaly,
3. interstitial edema,
4. enlarged pulmonary artery,
5. pleural effusion,
6. alveolar edema,
7. prominent superior vena cava,
8. and Kerley lines.
However, up to 20 % of patients diagnosed with heart failure had negative chest radiographs at initial emergency department evaluation.
Additionally, patients with PCWP values ≥30 mmHg where radiographic pulmonary congestion was absent in 39 % of patients
The X-ray technique impacts the detecting of volume overload. Ex, pleural effusion in intubated supine patient
3-Natriuretic peptides
High levels of BNP can be found with volume overload;
• Differential diagnosis,
• myocardial infraction
• pulmonary embolism
The greatest utility of BNP levels is in the absence of elevation, since low BNP levels have a high negative predictive value for excluding heart failure diagnosis
. On the other hand, high BNP levels can be nonspecific for volume overload [26].
4-Bioimpedance vector analysis
commonly used method for estimating body composition,
It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information
BIVA was examined as an indicator of fluid status compared to central venous pressure (CVP) in 121 critically ill patients
In this study patients were classified in three groups according to their CVP value:
• low (0 to 3 mmHg);
• medium (4 to 12 mmHg); and
• high (13 to 20 mmHg).
The agreement between BIVA and CVP indications was good in the high CVP group, moderate in the medium CVP group, and poor in low CVP group.
5-Thoracic ultrasound
PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines (“comet-tail images”)
Agricola et al., used thoracic ultrasound to detect “comet-tail images” authors found significant positive linear correlations between comet-tail images score and extra-vascular lung water determined by the PiCCO System, between comet score and PCWP, and between comet-tail images score and radiologic sings of fluid overload in the lungs
6- Vena cava diameter ultrasound
can also be use to assess volume status.
• Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium);
• volume depletion is considered with an IVC diameter <1.5 cm
• an IVC diameter >2.5 cm suggests volume overload.
Lyon et al. evaluated the inferior vena cava diameter (IVCd) during inspiration (IVCdi) and during expiration (IVCde), before and after blood donation of 450 mL. The difference was as (5.5 mm and 5.16 mm, respectively).
Zengin et al. evaluated the IVC and right ventricle (RVd) diameters and diameter changes compared to healthy volunteers.
the IVC during inspiration and expiration, and right ventricule diameter were significantly lower.
After fluid resuscitation, there was a significant increase in mean IVC diameters during inspiration and expiration as well as in the right ventricule diameter
Fluid overload management
Diuretic therapy
Diuretics, especially loop diuretics,
At this time, there is no evidence that favors ultrafiltration over diuretic use in volume overload patients
Numerous studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes
What should be the goal of urine output when using diuretics to manage fluid overload?
For some empirical observations 3–4ml/kg/h
Diuretics could be either administered by bolus or using a continuous infusion.
In one study diuretic infusion was associated with greater diuresis and this was achieved with a lesser dose
infusion was also associated with fewer adverse events such as worsening AKI, hypokalemia, and ototoxicity.
However, in the DOSE-AHF study, authors found that patients with acute heart failure may benefit from an initial bolus strategy
In order to avoid hypokalemia, administration of oral potassium it is easy.
Another strategy is the use of potassium-sparing diuretics like spironolactone.
Hypomagnesemia is frequently found during diuretic therapy, magnesium replacement can be achieved either intravenously or orally, typically with 20–30 mmoL per day.
Finally in some patients, chloride losses exceed sodium losses and hypochloremic metabolic alkalosis develops; this is usually corrected with the administration of potassium chloride and magnesium chloride.
A recent comprehensive review have shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide,
The reduced response to furosemide in AKI patients often requires the use of higher doses that may increase the risk of ototoxicity,
High doses of furosemide may also result in myocardia dysfunction secondary to furosemide induced vasoconstriction.
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of CRRT
CRRT provides a slower fluid removal over (IHD) resulting in more hemodynamic stability and better fluid balance control,
advantages of CRRT over IHD include:
• slower control of solute concentration
• reduce the risk of cerebral edema
Some large observational studies have suggested that CRRT is an independent predictor of renal recovery among survivors
Slow continuous ultrafiltration (SCUF) is a type of continuous renal replacement therapy that is usually performed with low blood flow rates (50 to 100 ml/min), and ultrafiltration rates between 100 and 300 ml/h according to fluid balance necessities.
Continuous veno-venous hemofiltration (CVVH) is another CRRT technique that allows meticulous, minute-to minute control of fluid balance by providing continuous fluid, electrolyte, and toxin clearance.
Another option for treating patients with fluid overload are the new smaller and more portable devices like the Aquadex FlexFlow System (Baxter Healthcare).
Costanzo et al. compare adjustable ultrafiltration using a small ultrafiltration device to the use of intravenous loop diuretics. The authors found a trend to longer time to recurrence of heart failure within 90 days event after hospital discharge in patients treated with the ultrafiltration device, and fewer heart failure and cardiovascular events.
Changes in renal function and the 90-day mortality were similar in both groups. However, more patients who were randomized to adjustable ultrafiltration experienced an adverse effect of special interest (p = 0.018) and a serious study product-related adverse events (p =0.026)
**Level 5 of evidence
Fluid management is crucial in post operative and critically ill patient in the setting of Intensive care unit. As restoring normal cardiac and organs function depends entirely on fluid status and hydration level of the organs, similarly cardiac function and cardiac output is depending on maintaining intra-vascular volume status.
On the other hand volume overload is linked to formation of edema , swelling of cells and organ dysfunction secondary to compression of blood vessels and deranged Hydrostatic vs oncotic pressure in encapsulated volume in particular.
Therefore,ascertaining volume status is pivotal in managing those patients, as its turning point in the whole management.
Assessment of volume status:
History and clinical examination is standerd in the care of hypervolemic patient.
Markers of volume status:
Pro-BNP is widely to reflect the volume staus , as it reflective of hypervolemia.
Bio-impedance vector analysis.
Thoracic US is a sensitive tool to assess volume status , as it would be reflecting engorgement of interstetium or fluid filled alveoli featuring B-lines (Comit-tail image ) consistent with hypervolemia.
Vena cava diameter :
less than 1.5 cm reflect hypovolemia and more than 2.5 cm , hypervolemia.
management:
Diuretics are still widely used in Hypervolemia.
A urine output of 3-4 ml/Kg/day is safe, as its matching capillary refill rate and would not result in hypovolemia.and intravascular depletion.
furosemide activity is futile in AKI due to decreased excretion of furosemide into tubular fluid and impaired response of Na-K-2Cl Co transporter.
high doses of furosemide might result in ototoxicity and cardiac toxicity.
It can be given in infusion or boluses.with debatable effect of each modality.
fluid overload is one of the major complications post-RTX
increase the accumulation of fluid especially in AKI and sepsis with fluid accumulation in the extracellular space.
AKI and fluid overload carry high mortality rates,
fluid overload assessment and recognition:
full physical examination and history taking to see if there is any symptoms or sign of fluid overloads like an SOB or lower limb oedema or raised JVP.
chest x ray demonstrating pulmonary venous congestion, ECG demonstrating atrial fibrillation, and reduced serum BNP (negative predictive value) can be used to assess fluid overload. The significance of lower limb edema, an increased JVP, and pulmonary rales is restricted. 20% of individuals with heart failure exhibit negative chest x-rays. Daily and cumulative fluid balance assessments are also significant methods for determining fluid overload. In conjunction with CVP, bioimpedance vector analysis (BIVA) can identify soft-tissue hydration with a measurement error of 2% to 3%. In congestive heart failure, a thoracic ultrasonography revealing B-lines, signifying fluid-filled alveoli, is beneficial. Ultrasound can also be used to measure the diameter of the inferior vena cava (>2.5 cm indicates fluid excess).
Fluid overload has been correlated with negative effects. Restoring cardiac output, blood pressure, and renal perfusion necessitates adequate fluid resuscitation. Inadequate fluid evacuation is linked to peripheral and pulmonary edema, which delays weaning from artificial breathing or wound healing. The goal of the study was the assessment and management of fluid overload in ICU patients.
Fluid resuscitation in patients with sepsis and those at risk for AKI leads to elevated extracellular volume, edema in different organs (hepatic renal, pulmonary, myocardial, gut and tissue) and fluid overload, resulting in impaired oxygenation, distorted tissue architecture, disturbed cell to cell interaction, with capillary blood flow and lymphatic obstruction, and organ dysfunction, especially in encapsulated organs like the liver and kidneys.
Fluid overload and outcomes:
Fluid overload and outcomes: In the presence of fluid overload, AKI is associated with increased 30-day and 60-day death rates. In the presence of ARDS, a greater positive fluid balance is related with increased mortality.
Fluid overload recognition and assessment:
This can be done by evaluating history and physical examination – history of heart failure, paroxysmal nocturnal dyspnea, third heart sound gallop on auscultation, chest x ray demonstrating pulmonary venous congestion, ECG demonstrating atrial fibrillation, and reduced serum BNP (negative predictive value) can be used to assess fluid overload. The significance of lower limb edema, an increased JVP, and pulmonary rales is restricted. 20% of individuals with heart failure exhibit negative chest x-rays. Daily and cumulative fluid balance assessments are also significant methods for determining fluid overload. In conjunction with CVP, bioimpedance vector analysis (BIVA) can identify soft-tissue hydration with a measurement error of 2% to 3%. In congestive heart failure, a thoracic ultrasonography revealing B-lines, signifying fluid-filled alveoli, is beneficial. Ultrasound can also be used to measure the diameter of the inferior vena cava (>2.5 cm indicates fluid excess).
The management of fluid excess includes the use of diuretics and extracorporeal therapy. Loop diuretics are symptomatic relief diuretics that can be administered either bolus or continuous infusion (infusion associated with lesser AKI, hypokalemia and ototoxicity and greater diuresis while boluses are better in acute heart failure). Potassium loss, hypomagnesemia, hypochloremia, and metabolic alkalosis are side effects of diuretics that can be treated with potassium chloride and magnesium chloride. Torsemide has been reported to be more successful in heart failure, while furosemide has a larger urine output in patients with acute kidney injury (AKI), but the response is diminished, necessitating higher doses that increase the risk of ototoxicity and cardiac dysfunction.
CRRT and IHD are used to increase pulmonary gas exchange and organ perfusion in diseases resistant to conventional therapy. Compared to IHD, CRRT delivers slower fluid evacuation with superior fluid management and hemodynamic stability. SCUF is performed with low blood flow and ultrafiltration rates, whereas CVVH offers continuous fluid, electrolyte, and toxin clearance. The Aquadex FlexFlow system is a portable option for treating individuals with fluid excess.
In conclusion, fluid overload is correlated with congestive heart failure, pulmonary edema, poor wound healing, reduced bowel function, and impaired cognition, and it increases the risk of death. Consequently, evaluation of fluid status and prompt treatment can prevent or mitigate the negative effects of fluid excess.
Adequate fluid resuscitation is essential to the restoration of cardiac, intravascular effective volume, and good peripheral perfusion. fluid overload is one of the major complication with acute renal failure, leads to overload, pulmonary edema. Fluid overload increases the critically ill patient. So timely fluid assessment for overload and timely management is crucial.
If patient is making output can start diuretics, otherwise need to initiate ultrafiltration.
level of evidence V
Summary of
Acute kidney injury and critical ill patient usually develop fluid overload
Management of fluid balance is crucial in critical ill patients’ management as fluid overload present as peripheral oedema and pulmonary oedema.
This study focuses on the evaluation and management of fluid overload in the intensive care unit.
Discussion:
The role of fluid therapy in the development of overload.
Critical ill patients such as patient with cardiogenic or septic shock are in need to restore circulation (BP and cardiac output) and renal perfusion.
Adequate treatment with intravenous solutions can also prevent or limit subsequent AKI.
Critical ill patient has an increased capillary leak. intravenous solutions leading to oedema and fluid overload. These result in impaired oxygen and metabolite diffusion, distorted tissue architecture.
Obstruction of capillary, blood flow and lymphatic damage. These effect usually in encapsulated organ such as kidney or liver.
Fluid overload and outcomes:
Several observational studies have demonstrated a correlation between fluid overload and mortality in critical ill patients with acute respiratory distress syndrome, acute lung injury, sepsis and AKI.
Lungs are one of the organs in which adverse effects are most evidence.
Several studies have provided evidence associating positive fluid balance with poor nephrology outcome.
Fluid status assessment:
Several methods exist to evaluate fluid status although most of them are inaccurate.
Clinical evaluation include history and physical examination include: dyspnoea, pulmonary rate, lower limb oedema and distended jugular veins.
Chest radiograph: signs of overload in radio phrenic angles, distended upper loop vessels, cardiomegaly, intestinal oedema, enlarge pulmonary artery, pleural effusion, alveolar oedema, prominent superior vena cava, kidney lines. Natriuretic peptides high BNP can be found with volume overload and also in pulmonary embolism, myocardial infraction and renal failure.
Bioimpedance vector analysis is a commonly used method for estimating body composition, specifically detection soft tissue denaturation with a 2-3% measurement error.
Thoracic ultrasonographic artifact known as B-lines that suggest thickened interstitial or fluid filled alveolar can be detected using thoracic ultrasound PCWP and fluid in lungs have been correlated with the presence of B-lines in patients with congestive heart failure.
Vena cava diameter ultrasound normal dimeter of IVC is 1.5-2.5 cm
Volume deletion is considered with an IVC diameter > 2.5cm suggest volume overload.
Fluid overload management:
Loop diuretic use to treat fluid overload are load in patients with AKI. number of studies have demonstrated that more aggressive use of loop diuretics to achieve greater volume normal is associated with improved outcomes. Urine 2output 3-4 ml/kg /h rarely cause intravascular volume depletion.
Diuretics can be given ones or continues infusion. Infusion fewer adverse event such as worsen AKI, hypokalaemia and ototoxicity.
Although patient with HF benefit from initial bolus strategy.
High doses of frusemide may also result in myocardial dysfunction secondary to fursmide induced vasoconstriction
Extracorporeal therapy:
Refractory overload to medical therapy
Requires use of extracorporeal therapies such as CRRT or IHD.
In absence of definite data to support the use of particular type of renal
replacement therapy one should consider CRRT and IHD.
Other modalities of RRT can be used such as ( SCUF , CCVH).
Other option for treating patient with fluid overload are the new smaller and more portable devices like Aguadex Flex Flow System.
Conclusion:
Fluid overload complication included congestive heart failure, pulmonary oedema, delay wound healing, tissue breakdown and impaired bowel function.
Fluid overload increased the mortality especially among critical ill patients.
Volume status assessment in critical ill patient play an important role of early management of these patients.
Loop diuretics are frequently used as initial therapy to treat critical ill patients with fluid overload.
RRT use to treat fluid overload in critical ill patient and ultrafiltration dependon accurate estimation of patient fluid status
evidence level is 5
Fluid overload in the ICU: evaluation and
Management.
Fluid overload is one of the major problem associating with AKI patients in critical area which is associated with increasing in morbidity and mortality , so we should try to keep our patients euvolemic by Strict fluid intake and output chart, diuretics in need or CRRT. Many studies have shown an association
between fluid overload and mortality.
Discussion:
Adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or septic shock so we should be oriented about how to evaluate the volume status, to select appropriate solution for volume repletion, and maintenance and modulation of the tissue perfusion.
Fluid therapy such as crystalloid which used to expand intravascular volume but it may has adverse effects in critically ill due to sepsis itself which increase capillaries leak to interstitial tissue and lead to fluid overload which affect metabolic status and organ dysfunction.
Edema is attributed to a combination of increased capillary permeability to proteins and increased net trans-capillary hydrostatic pressure through reduced pre-capillary vasoconstriction.
Fluid overload and outcomes.
Many studies have shown a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
Fluid overload associated with high hospital stay, high mechanical ventilator.
Fluid overload recognition and assessment.
Mainly depends on strict intake and output chart, we should keep in mind that if percentage of fluid overload adjusted for body weight above 10% is associated with high mortality.
Which calculated by % Fluid overload (total fluid in−total fluid out) /admission body weight x 100.
Fluid status assessment.
A-History and physical examination:
past history of heart failure, SOB, paroxysmal nocturnal dyspnea and third heart sound gallop which indicate HF.
Signs: such as presence of jugular venous distension, at rest or inducible, had a sensitivity (81 %), and a specificity (80 %).
B-Chest radiography.
Radiographic sings of volume overload include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent
superior vena cava, and Kerley lines.
But the sensitivity, specificity, and accuracy of supine chest X-ray was reported to be as low as 60 %, 70 %, and 67 % respectively.
C-Natriuretic peptides.
High with CHF and ESRD patients but it in not sensitive but low BNP levels have a high negative predictive value for excluding heart failure diagnosis.
D-Bioimpedance vector analysis.
Simply, It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
The combined evaluation of peripheral tissue hydration (BIVA)
and central filling pressure (CVP) could provide a useful clinical assessment instrument in the planning of fluid therapy in critically ill patients, particularly in those with low CVP.
E-Thoracic ultrasound.
Thickened interstitial or fluid-filled alveoli appear as Sonographic artifacts which is called as B-lines (“comet-tail images”)
F-Vena cava diameter ultrasound.
Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Ultrasonography can measure IVC diameter and right ventricle diameter which is considered practical noninvasive instrument for fluid status estimation and for evaluating the response to fluid therapy in critically ill patients.
Fluid overload management.
Diuretic therapy.
Many studies shown that more aggressive use of loop diuretics to achieve greater volume removal is associated with improved outcomes.
Some empirical observations have shown that a urine output of 3–4 ml/kg/h rarely causes intravascular volume depletion as capillary refill can meet such rates in almost all patients.
Furosemide electrolyte imbalance should be followed as hypokalemia, hypomagnesemia and hypochloremic metabolic alkalosis.
Extracorporeal therapies.
CRRT over IHD include: a slower control of solute concentration avoiding large fluctuations and fluid shifts, which reduce the risk of cerebral edema, also SCUF or CVVHF can be used .
Conclusions.
Volume overload in critical patients is associated with high morbidity and mortality rate, history, physical examination and investigational equipment such as CXRY, USG of chest , IVC diameter assessment are so important to assess and manage the volume overload which is started by diuretics and if resistant we can start to remove the fluid by extracorporeal therapies.
level of evidence :V
Fluid replacement in critically ill patients is mainstay of treatment and to create that delicate balance to avoid fluid overload is real challenge for clinicians.This review has shed light on this important aspect of management.
In critically ill patients, adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion in patients with cardiogenic or septic shock. The administration of crystalloids in these sick patients can lead to tissue edema owing to the associated increased capillary permeability ultimately leading to organ dysfunction.
Fluid overload is not only a consequence of fluid therapy but also occurs during severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products and altered organ microcirculation.
Fluid overload and outcomes
Several studies have shown increased mortality associated with fluid overload in critically ill patients.Lungs are one of the organs in which adverse effects of fluid overload are most evident, which can lead to acute pulmonary edema or acute respiratory distress syndrome.
Fluid overload recognition and assessment
This can be done by different ways like daily measurement of fluid in and out, Cumulative fluid balance assessment, percentage of fluid overload adjusted for body weight.
History and physical exam.
Diagnostic tests like
CXR
ECG
Serum BNP
Bioimpedance vector analysis
Bioelectrical impedance analysis is a commonly used method for estimating body composition, specifically detecting soft tissue hydration with a 2–3 % measurement error.
It is a noninvasive, inexpensive and highly versatile test that transforms electrical properties of tissues into clinical information.
Bioimpedance vector analysis (BIVA) measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration.
Thoracic ultrasound
Sonographic artifacts known as B-lines that suggest thickened interstitial or fluid-filled alveoli can be detected using thoracic ultrasound. PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines (“comet-tail images”) in patients with congestive heart failure.
Vena cava diameter ultrasound.
The measurement of the inferior vena cava (IVC) diameter can also be use to assess volume status. Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Fluid overload management
Diuretic therapy
Diuretics, especially loop diuretics, remain a valid therapeutic alternative for relieving symptoms and improving pathophysiological states of fluid overload such as congestive heart failure and in patients with AKI.
Diuretic infusion or bolus dose has not shown much difference in terms of outcome.
At the same time, there is no evidence that favors ultrafiltration over diuretic use in volume overload patients with or without AKI in terms of less progression of AKI, improved clinical out- comes or reduce incidence of AKI .
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as continuous renal replacement therapies since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
The choice of therapy like CVVH, SCUF etc depends upon clinical condition , available resources and expertise.
The ultimate goal is to preserve tissue perfusion, optimizing fluid balance by effectively removing fluid without compromising the effective circulating fluid volume; therefore, meticulous monitoring of fluid balance is critical for all patients.
Fluid overload has also been related to increased mortality. The optimal assessment of volume status in critically ill patients is of vital importance particularly dur- ing the early management of these patients.
Narrative review
level 5
Fluid overload has been seen to be associated with adverse outcomes. Adequate fluid resuscitation is essential to restore cardiac output, blood pressure and renal perfusion. Inadequate fluid removal is associated with peripheral edema and pulmonary edema, retarding weaning from mechanical ventilation or wound healing. The study focused on the evaluation and management of fluid overload in ICU patients.
Role of fluid therapy in fluid overload development: Fluid resuscitation in patients with sepsis and those at-risk of AKI leads to elevated extracellular volume, leading to edema in different organs (hepatic renal, pulmonary, myocardial, gut and tissue) and fluid overload, resulting in impaired oxygenation, distorted tissue architecture, disturbed cell to cell interaction, with capillary blood flow and lymphatic obstruction, leading to organ dysfunction, especially in encapsulated organs like liver and kidneys.
Fluid overload and outcomes: Fluid overload in critically ill patents with AKI, ARDS, acute lung injury, and sepsis is associated with increased mortality. AKI is associated with increased 30-day and 60-day mortality, in presence of fluid overload. Higher positive fluid balance in presence of ARDS is associated with increased mortality.
Fluid overload recognition and assessment: It can be done by assessing history and physical examination – history of heart failure, paroxysmal nocturnal dyspnea, third heart sound gallop on auscultation, chest x ray showing pulmonary venous congestion, ECG showing atrial fibrillation, reduced serum BNP (negative predictive value), can be utilized to assess fluid overload. Lower limb edema, elevated JVP, and pulmonary rales have limited role. 20% of heart failure patients have a negative chest x-ray. Daily fluid balance and cumulative fluid balance assessment are also important tools to assess fluid overload. Bioimpedance vector analysis (BIVA) detects soft-tissue hydration with 2-3% measurement error, and can be useful if used in combination with CVP. Thoracic ultrasound showing B-lines, suggesting fluid-filled alveoli, are useful in congestive heart failure. Inferior vena cava diameter using ultrasound is another way to assess volume status (>2.5 cm suggesting fluid overload).
Fluid overload management includes use of diuretics and extracorporeal therapies. Diuretics include loop diuretics for relieving symptoms, which can be given either as bolus or continuous infusion (infusion associated with lesser AKI, hypokalemia and ototoxicity and greater diuresis while boluses are better in acute heart failure). Diuretics are associated with potassium loss, hypomagnesemia, hypochloremia, and metabolic alkalosis which can be managed with potassium chloride and magnesium chloride. Torsemide has been found to be more effective in heart failure while furosemide use had better urine output in AKI patients, although the response is reduced and hence requires higher doses increasing the risk of ototoxicity and myocardial dysfunction.
Extracorporeal therapies like CRRT (continuous renal replacement therapies) and intermittent hemodialysis (IHD) are utilized in conditions refractory to medical therapies to improve pulmonary gas exchange and organ perfusion. CRRT provides slower fluid removal with better fluid control and hemodynamic stability than IHD. Slow continuous ultrafiltration (SCUF) is performed with low blood flow rates and low ultrafiltration rates while continuous veno-venous hemofiltration (CVVH) provides continuous fluid, electrolyte, and toxin clearance. Portable devices like Aquadex FlexFlow system are also available to treat patients with fluid overload.
To conclude, fluid overload is associated with congestive heart failure, pulmonary edema, poor wound healing, impaired bowel function, and impaired cognition, and leads to increased mortality. Hence assessment of fluid status and timely action can prevent or minimize adverse effects of fluid overload.
Level of evidence: Level 5 – narrative review
Summarise this article
Introduction:
Volume overload is frequent complication faced in ICU settings, with difficulty in recognition, and it has been associated recently with adverse outcomes and mortality.
The role of fluid therapy in the development of fluid overload:
Adequate fluid resuscitation is essential to the restoration of cardiac output, systemic blood pressure and renal perfusion prevent acute kidney injury in patients with cardiogenic or septic shock.
over time patients experienced an increased capillary leak intravenous solutions will leave the circulation and distribute in the extracellular volume leading to edema and to fluid overload, results in impaired oxygen and metabolite diffusion, distorted tissue architecture, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may then contribute to progressive organ dysfunction.
Fluid overload and outcomes:
Fluid overload %= total fluid in−total fluid out /admission body weight x100. A formula used to estimate fluid overload if more than 10%, associated with adverse outcomes, such as difficult to wean from mechanical ventilator, organ dysfunction ie.. AKI, requirement of renal replacement therapy, and increased mortality.
Fluid overload recognition and assessment:
1. Daily fluid balance: daily difference in all intakes and all outputs, which frequently does not include insensible losses.
2. Cumulative fluid balance: sum of each day fluid balance over a period of time.
3. Fluid overload: usually implies a degree of pulmonary edema or peripheral edema.
4. Fluid accumulation: positive fluid balance, with or without linked fluid overload.
5. Percentage of fluid overload adjusted for body weight: cumulative fluid balance that is expressed as a percent. A cutoff of ≥10 % has been associated with increased mortality.
Clinical assessment:
– History and physical examination: history of heart failure, raised JVP, lower limb edema, pulmonary crackles, SOB, PND’s…etc.
– Chest x ray: dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines. However 20 % have negative imaging, sensitivity of 60%, specificity of 70% and 67% accuracy.
– Natriuretic peptides (BNP): Has a high negative predictive value, positive results indicated Rt. Ventricular strain- PE, volume overload, and MI.
– Bioimpedance vector analysis: measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration, when combined to CVP measurement could provide a good clinical assessment for volume overload.
– Thoracic ultrasound: can detect a B-lines “comet tail images” that suggest thickened interstitial or fluid-filled alveoli.
– Vena cava diameter ultrasound: diameter < 1,5 cm indicates volume contraction, and >2,5 cm indicates volume overload.
Fluid overload management:
– Diuretics- loop diuretics, potassium sparing diuretics.
– Extracorporeal therapy – Intermittent HD , or continuous renal replacement therapy (CVVH, SCUF).
Conclusion:
Volume overload is a frequently faced problem in ICU with high adverse outcomes, difficult to detect and needs an excellent knowledge to define and treat.
Renal replacement therapies are often required for optimal volume management in critically ill patients with fluid overload.
What is the evidence provided by this article?
Level of evidence V, erratic review.
Summary:
In critically ill patients, adequate fluid resuscitation is essential to restore cardiac output, systemic blood pressure, and renal perfusion. Achieving an appropriate level of volume management requires knowledge of the underlying pathophysiology, evaluation of volume status, selection of appropriate solution for volume repletion, and maintenance and modulation of the tissue perfusion.
Fluid overload and outcomes:
Several observational studies have demonstrated a correlation between fluid overload and mortality in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI.
Fluid overload recognition and assessment:
Requires accurate documentation of intakes and outputs; however, there is a wide variation in how this information is recorded, reviewed and utilized.
Some useful definitions:
Daily fluid balance: difference in all intakes and outputs, frequently not including insensible losses.
Cumulative fluid balance is the sum of each day’s fluid balance over time.
Fluid overload: usually implies a degree of pulmonary edema or peripheral edema.
Fluid accumulation: positive fluid balance, with or without linked fluid overload. Percentage of fluid overload adjusted for body weight: cumulative fluid balance that is expressed as a percent. A cutoff of ≥10 % has been associated with increased mortality. Fluid overload percentage can be calculated using the following formula:
% Fluid overload=((total fluid in- total fluid out)/admission body weight*100).
Fluid status assessment:
Fluid overload management:
Level of evidence:
Level 5 (review article).
Summary of the article
“Fluid overload in the ICU – evaluation and management”
Fluid overload in the ICU; Underlying
· A consequence of fluid therapy.
· Severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products and altered organ microcirculation.
Fluid overload; outcome
· Several observational studies have demonstrated a correlation between fluid overload and mortality in critically ill patients(ARDS, ALI, AKI and Sepsis).
· Body weight of over 10 % had significantly more respiratory failure, need of mechanical ventilation, and more sepsis.
· AKI patients with fluid overload had increased 30 day and 60 day mortality.
· Lower level of fluid accumulation at initiation of dialysis and at dialysis cessation, is associated with better survival.
Fluid overload; Evaluation and assessment:
1. History and physical examination.
· History of heart failure.
· SOB, PND.
· Third heart sound gallop, Pulmonary rales, lower extremity edema and jugular venous distention.
2. Diagnostic studies; ECG, CXR and serum BNP.
3. Bioimpedance vector analysis (BIVA); transforms electrical properties of tissues into clinical information. Bioimpedance vector analysis (BIVA) measures whole body fluid volume and is based on patterns of the resistance-reactance graph, relating body impedance to body hydration.
4. CVP;
· low (0 to 3 mmHg).
· medium (4 to 12 mmHg).
· high (13 to 20 mmHg).
5. The combined evaluation of peripheral tissue hydration (BIVA) and central filling pressure (CVP) could provide a useful clinical assessment instrument in the planning of fluid therapy in critically ill patients.
6. Thoracic ultrasound; Sonographic artifacts known as B-lines(“comet-tail images”), that suggest thickened interstitial or fluid-filled alveoli.
7. Vena cava diameter ultrasound; Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium); volume depletion is considered with an IVC diameter <1.5 cm while an IVC diameter >2.5 cm suggests volume overload.
Fluid overload;Management
1. Diuretics; a UOP of 3-4 ml/Kg/hr rarely causes intravascular volume depletion.
2. Ultrafiltration via CRRT, if hemodynamically unstable. Otherwise UF using IHD is an alternative.
3. Adjustable ultrafiltration using Aquadex FlexFlow System (Baxter Healthcare).
What is the evidence provided by this article?
This is a narrative review article.
Level of evidence grade 5.
Club 6; hypervolemia in ICU, diagnosis and management
Summary
· Volume overload is one of the most important predictors of patient outcomes in ICU and in critically ill patients.
· Assessment of the volume status is crucial and assessment of the fluid balance (with input and output) is essential.
· Treatment by loop diuretics or CRRT in diuretic resistant cases.
· In case of sepsis, initial fluid resuscitation is essential to maintain organs perfusion and prevent AKI, however later on, the intra-capillary and extra-capillary leak will lead to interstitial edema and escape of fluids extravsacular.
· Fluid overload > 10 % of dry weight is associated with higher mortality and morbidity.
· Fluid balance, total input and output of fluids and daily weight are essential to determine the fluid balance.
· lung is the most sensitive organ to fluid overload with risk of pulmonary edema, increase need for mechanical ventilator and worse outcome.
· Many tools can be utilized as CXR, ecg, lung US, IVC diameter and collapsibility index.
Level of evidence: narrative review (level V)
· In acute respiratory distress syndrome and following major surgery, patient may benefit from fluid restriction
· Over load and pulmonary edema in critically ill patients, may retard weaning from mechanical ventilation and wound healing
Discussion
· crystalloids solutions are essential for the treatment of patients with or at risk of AKI, and also in patients with sepsis
· over time due to increased capillary leak, IV fluids will lead to edema and to fluid overload.
· Edema may lead to impaired oxygen and metabolite diffusion, obstruction of capillary blood flow and lymphatic drainage, and disturbed cell to cell interactions that may lead to progressive organs dysfunction, mainly liver and kidney
· Fluid over load could happen due to severe sepsis secondary to the release of complement factors, cytokines and prostaglandin products
· AKI patients with fluid overload had increased 30 day and 60-day mortality
· patients with septic shock and acute lung injury who received conservative fluid management, had better outcome
· The Vasopressin in Septic Shock Trial (VASST) found that higher positive fluid balance correlated with increased mortality and the highest mortality rate observed in those with high CVP
Fluid overload recognition and assessment
1. Daily fluid balance
2. Cumulative fluid balance
3. Fluid overload
4. Fluid accumulation
5. Percentage of fluid overload adjusted for body weight
Fluid status assessment
· History and physical examination
· Chest radiography. sings of volume overload include:
dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines
· High levels of BNP can be found with volume overload; however, some conditions like myocardial infraction and pulmonary embolism can cause elevated levels of BNP
· Bioimpedance vector analysis
· Thoracic ultrasound
· Vena cava diameter ultrasound
Fluid overload management
Diuretic therapy:
· some authors advocate that diuretic infusion is superior to boluses since urinary output could be maintain easily
· infusion associated with fewer adverse events such as worsening AKI, hypokalemia, and ototoxicity
· Hypomagnesemia is frequently found during diuretic therapy; magnesium replacement can be achieved either intravenously or orally
· A recent review shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide
· torsemide can be more efficacious than furosemide in patients with heart failure
Extracorporeal therapies
Advantages of CRRT over IHD include:
· more hemodynamic stability and better fluid balance control
· slower control of solute concentration avoiding large fluctuations and fluid shifts
· allows to perform the treatment with relatively simple and user friendly machines
Slow continuous ultrafiltration (SCUF): usually performed with low blood flow rates (50 to 100 ml/min), and ultrafiltration rates between 100 and 300 ml/h
Continuous veno-venous hemofiltration (CVVH):
New smaller and more portable devices like the Aquadex FlexFlow System
Conclusions
· Congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function are associated with fluid overload
· Fluid overload has also been related to increased mortality
· Loop diuretics are frequently used as the initial therapy to treat critically ill patients with fluid overload
· Renal replacement therapies are often required for optimal volume management in critically ill patients with fluid overload
The level of evidence is 5
Summary of the Article;
Fluid overload is commonly occur in ICU setting specially in patient with AKI, and it should be considered as a mediator of adverse outcome.
Discussion;
The role of fluid therapy in the development of fluid overload;
Fluid overload and outcome;
Fluid recognition and assessment;
Fluid status assessment;
Fluid overload management;
Conclusion;
Overload associated adverse effects include; CHF, Pulmonary edema, Delyed wound healing, and impaired bowel function.
Accurate assessment of fluid status is vital and monitor fluid replacement is mandatory to avoid complication associated with fluid overload.
Level of evidence ((V))
Introduction:
Correct fluid volume management requires knowledge of the good knowledge of pathophysiology, volume status assessment, choosing the correct solution for volume replacement, and maintaining tissue perfusion. The crystalloids solutions expands the extracellular compartment, with time and due to increased capillary leak in critically ill patients, the IV solutions leave the intravascular space and distribute in the extracellular space, leading to edema and to fluid overload. This leads to impaired oxygen and metabolite diffusion, tissue disruption, impaired capillary blood flow and lymphatic flow, disturbed intrecellular interactions, all leading to progressive organ dysfunction. These effects are seen mostly in encapsulated organs.
Fluid overload (an increase in body weight of over 10 %) in critically ill patients with acute respiratory distress syndrome, acute lung injury, sepsis, and AKI, led to higher incidence of respiratory failure, need of mechanical ventilation, and sepsis. AKI patients with fluid overload had higher 30-day and 60-day mortality.
Studies suggested that positive fluid balances is associated with poorer respiratory outcomes and that conservative fluid management protocols had lower cumulative fluid balance, better oxygenation index and lung injury score, more ventilator-free days, and reduced ICU length of stay.
Fluid overload recognition and assessment:
Fluid overload diagnosis and assessment in critically ill patients requires meticulous intakes and outputs charting. The following definitions are helpful:
Daily fluid balance: this is the difference in intakes and outputs, it does not usually include insensible losses.
Cumulative fluid balance: sum of fluiddf balances over a period of time.
· Fluid overload: usually implies a degree of pulmonary edema or peripheral edema.
· Fluid accumulation: this is the positive fluid balance, with or without fluid overload.
· Percentage of fluid overload adjusted for body weight: this is the cumulative fluid balance expressed as a percent. ≥10 % is associated with higher mortality.
There are several methods to evaluate fluid status; however, most of the tests currently used to evaluate fluid overload are inaccurate.
These include:
· History and physical examination along with routine diagnostic studies. Pulmonary rales, lower extremity edema, and jugular venous distention may have significant limits in fluid overload assessment.
· High levels of Natriuretic peptides: however, many clinical conditions are associated with high and low levels BNP such as myocardial infraction and pulmonary embolism obesity, and renal failure. low BNP levels have a high negative predictive value for excluding heart failure diagnosis. On the other hand, high BNP levels can be nonspecific for volume overload.
· Bioimpedance vector analysis: the Bioelectrical impedance analysis is commonly used for estimating body composition, it detects soft tissue hydration with a 2–3 % measurement error. It is a non-invasive, non-expensive, and highly versatile test.
· Thoracic ultrasound: the B-lines (comet-tail images) on thoracic US suggest thickened-fluid-filled alveoli.
· Vena cava diameter ultrasound: the IVC diameter can also be used for volume status assessment. Normal diameter of IVC is 1.5 to 2.5 cm. Bedside IVC and right ventricle diameter measurement is a practical non-invasive test for assessment of fluid status and the response to fluid therapy in critically ill patients.
Fluid overload management:
· Diuretic therapy:
· Diuretics, especially loop diuretics, relieve symptoms, and improve effects of fluid overload. There is no evidence favouring ultrafiltration (UF) over diuretic use in volume overload patients with or without AKI. Aggressive use of loop diuretics associated with improved outcomes. Diuretics infusion- compared to boluses -resulted in more diuresis with a lesser dose, and fewer adverse side effects. Electrolytes levels and acid-based status should be monitored closely. High doses of furosemide may result in MI due to furosemide-induced vasoconstriction.
· Extracorporeal therapies
· If medical therapy fails, extracorporeal therapies such as continuous renal replacement therapies (CRRT) can be used. Studies found that CRRT is an independent predictor of renal recovery among survivors. CRRT and IHD should be considered as complementary therapies. CRRT is preferred to intermittent haemodialysis (IHD) as it offers:
· Slower fluid removal leading to more hemodynamic stability,
· Better fluid status control,
· Slower control of solute concentration avoiding large fluctuations and fluid shifts, which may lead to cerebral edema,
· Great flexibility of treatment adjustment to patient’s needs at any time,
· Ability to perform the treatment with simple and user friendly machines.
Other modalities are: Slow continuous ultrafiltration (SCUF) (a type of CRRT that is usually performed with low blood flow rates), Continuous veno-venous hemofiltration (CVVH), and the new smaller and more portable devices like the Aquadex FlexFlow System.
Role of IV fluid with volume overload development:
Fluid overload outcomes:
Fluid overload assessment:
Fluid overload management:
Level of evidence is 5
Background
Patients with acute kidney injury, in critical ill conditions, have been frequently found to experience fluid overload. This is often a consequence of resuscitation or severe acute kidney injury (AKI). It is also related to adverse outcomes. Observational studies have shown a link between fluid overload and mortality. Acute respiratory distress syndrome and post-operative states require restrictive fluid management, because it reduces the length of mechanical ventilation and the incidence of cardiopulmonary complications. Fluid overload leads to pulmonary and peripheral edema. The review focused on evaluation and management of fluid overload in the intensive care unit (ICU).
Discussion
The role of fluid therapy in the development of fluid overload
For patients who are critically ill, cardiogenic or septic shock is more prevalent. Therefore, fluid resuscitation is often the management of choice, to restore cardiac output, systemic blood pressure and renal perfusion. This depends on understanding the underlying pathology, evaluating the volume status, selection of the appropriate fluid for administration, and maintain and adjusting it for adequate tissue perfusion.
Critically ill patients benefit from crystalloid solutions initially, but over time, they are prone to the risk of increased capillary leaks, leading to increased extracellular volume and thereby causing edema and fluid overload. This causes impaired oxygenation in the lung tissue, distorted tissue architecture, obstruction of capillary flow and lymphatic drainage. These will eventually lead to organ dysfunction. Sepsis may also cause increased capillary permeability.
Fluid overload and outcomes
Bouchard et al showed that patients with fluid overload of more than 10% of their body weight had significantly more respiratory distress, which required mechanical ventilator support, and increased incidence of sepsis. In the pediatric population, a multicenter prospective study found that the percentage of fluid accumulation at the start of CRRT was significantly lower in the survivors.
Acute pulmonary edema and acute respiratory distress syndrome are the most evident adverse effects of fluid overload. Many studies have proven that the patients with acute lung injury and septic shock, who were resuscitated with conservative fluid management had lower mortality rates.
Fluid overload recognition
%fluid overload = (total fluid in-total fluid out)/admission body weight x 100
Fluid status assessment
The normal diameter of the inferior vena cava (IVC) is 1.5 to 2.5cm
In volume depletion, the IVC diameter is <1.5cm
In volume overload, the IVC is >2.5cm
Fluid overload management
1.Loop diuretics relieve symptoms and pathophysiologic states of fluid overload in patients with AKI
Diuretics can be administered by bolus or as a continuous infusion
Requires monitoring of electrolytes
Urine output needs to be monitored.
2.Extracorporeal therapies
Continuous renal replacement therapy in critically ill patients results in more hemodynamic stability and better fluid balance control and reduces the risk of cerebral edema
Slow continuous ultrafiltration can also be used
Continuous veno-venous hemofiltration is an alternative to provide continuous fluid, electrolyte and toxic clearance.
Conclusion
Some of the complications of fluid overload include congestive heart failure, pulmonary edema, delayed wound healing, tissue breakdown and impaired bowel function. Fluid overload has been associated with increased mortality. Optimal assessment of fluid status is important in early management of the patients, to maintain hemodynamic stability and optimize organ function. Initial therapy is the use of diuretics, but they may not always be ideal due to renal dysfunction. Renal replacement therapies are usually needed for volume management in critically ill patients due to underlying kidney injury.
Level of evidence is Level V as this is a narrative review
Summary:
In critical care units fluid overload frequently found in AKI and related to adverse outcomes, like increased mortality and several complications like pulmonary edema, cardiac failure, delayed wound healing, tissue breakdown, and impaired bowel function. Management of fluid balance becomes a central component of critically ill patients.
Appropriate fluid resuscitation is essential in critically ill patients to restore cardiac output, systemic blood pressure and renal perfusion. For this purpose evaluation of volume status, selection of appropriate solution for volume repletion, and maintenance of tissue perfusion is the priority.
Recent studies have established a correlation between fluid overload and mortality in critically ill patients. Recognition and assessment of fluid overload need accurate documentation of intake and output. Accurate volume status evaluation is essential for appropriate therapy since errors of volume evaluation can result in either in lack of essential treatment or unnecessary fluid administration, and both scenarios are associated with increased mortality.
Loop diuretics remain the treatment option of fluid overload. Fluid overload refractory to medical therapy may requires extracorporeal therapies.
Level 5 evidence
Thank you.
VI. Transplant Renal Vein Thrombosis
1. Please summarise this article
Introduction
TRVT is one of the major causes of early graft dysfunction & almost inevitably leads to graft loss.
The prevalence of TRVT is 0.1% – 4.2 % of all TXs; higher in DD than in LD TXs.
Causes
Donor factors:
·Use of a donor’s RK (short vein & long artery)
·Multiple graft vessels
·Prolonged ischemia time
·Vascular injuries
·Older age of donors(donor hypotension with IRI)
Recipient factors:
Extremes of age
Pre-TX dialysis modality; PD more than HD
Perioperative hemodynamic status
Primary renal (e.g. membranous nephropathy)
Operative factors:
Rena vein kink
Compression by hematomas or lymphoceles
Anastomotic stenosis
Extension of a DVT
Compression of the renal vein by the renal artery ( contra-lateral TXs-RK into LIF & LK into the RIF).
Immunosuppression:
Prothrombotic drugs (Cyclosporine, OKT3, high doses of pulsed methyl prednisolone, & ATG)
Clinical features:
Rapid onset of oliguria or anuria
Hematuria
Worsening graft function
Painful swollen graft which may progress to rupture
Chronic vein thrombosis is usually asymptomatic.
PE may complicate TRVT.
Diagnosis
1.Highly suspicious clinical presentation
2.Doppler USS:
Allows early detection
Noninvasive
Easily available
Safe in the hands of a trained & skilled operator
Duplex USS features of TRVT:
a.Reversed arterial diastolic flow (arterial wave form +ve during systole & -ve during diastole)
b.A spike-like systolic component
c.Non-visualization of the renal vein.
Typical shapes of reversed diastolic waveforms:
i- type 1 or “transient” waveform (the reversed diastolic waveform returns to baseline before end
Diastole)
ii- type 2 or “plateau” waveform (a flat reversed flow remains constant throughout diastole)
iii- type 3 or “inverted M” waveform (reversed flow throughout diastole has mid-diastolic deceleration).
Differential diagnosis of isolated reversed or absent diastolic arterial:
i- Severe AR
ii- Severe ATN
iii-Hematoma
iv-Vascular kink
TRVT remains an uncommon cause of reversed diastolic flow.
3. MRI
Magnetic resonance angiography is increasingly being reliably used.
Limitations:
Inability to image patients with pace makers
Greater cost
Lack of portability
Prolonged examination time (not suitable in the critically ill)
Management
A. Thrombolytic therapy:
Suitable for TRVT in late TX period
Risk of life-threatening hemorrhage.
B. Surgical thrombectomy:
TRVT in the early post-TX.
Risks of anesthesia & post-op infection in an immunosuppressed state.
C. Combined percutaneous mechanical thrombectomy & localized catheter-directed thrombolysis: safe & effective
Prevention
Meticulous surgical techniques
Sufficient training in the techniques of anastomosis
Ipsilateral TX (R to R & left to left) whenever possible.
Attention to intravascular volume status (TE Doppler more accurate than CVP)
Meticulous clinical assessment & duplex USS monitoring early post-TX & timely intervention.
Low-dose aspirin & LMWH may benefits in preventing TRVT in high-risk patients.
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4. What is the level of evidence provided by this article?
Level V
Thank you.
Fluid overload is frequently found in critically ill patients, it has significant adverse outcomes and increases the mortality; hence, manage and optimization of fluid balance becomes a central component of the management of critically ill patients.
The role of fluid therapy in the development of fluid overload
– Adequate fluid resuscitation is essential to the restoration of volume.
– Achieving an appropriate level of volume management requires knowledge of the underlying pathophysiology, evaluation of volume status, selection of appropriate solution.
– Critically ill patients have an increased capillary leak intravenous leading to edema and to fluid overload that result in progressive organ dysfunction.
Fluid overload and outcomes
Several observational studies have demonstrated a correlation between fluid overload and mortality in critically
ill patients with ARDS, ALI, sepsis, and AKI and reduced renal recovery.
Fluid overload recognition and assessment:
-Accurate documentation of intakes and outputs; by using one of the following: daily fluid balance, cumulative fluid balance, fluid overload , fluid accumulation, percentage of fluid overload adjusted for body weight.
– History and physical examination: Sings like rales, edema, and elevated JVP. The combination of these signs had a sensitivity of 58 % and specificity of 100 %
-Chest radiography finding include dilated upper lobe vessels, cardiomegaly, interstitial edema, enlarged pulmonary
artery, pleural effusion, alveolar edema, prominent superior vena cava, and Kerley lines. However, up to
20 % of patients had negative chest radiographs, especially in late-stage heart failure. Technique and severty of overload contribute to detecting finding.
-Natriuretic peptides
low BNP levels have a high NPV for excluding heart failure diagnosis
High levels of BNP nonspecific for volume overload, can be high in other cardiac condition. Therefore, we have to take in account the baseline BNP level.
– Bioimpedance vector analysis BIVA
Commonly used method for estimating body composition, specifically detecting soft tissue hydration.
The agreement between BIVA and CVP indications is good, combining BIVA and CVP could provide a
useful tool in the planning of fluid therapy.
– Thoracic ultrasound; B-lines that suggest thickened interstitial or fluid-filled alveoli can be
PCWP and fluid accumulation in lungs have been correlated with the presence of B-lines
Vena cava diameter ultrasound
Normal diameter of IVC is 1.5 to 2.5 cm; volume depletion is considered with an IVC diameter <1.5 cm while an
IVC diameter >2.5 cm suggests volume overload.
Fluid overload management
Diuretic therapy
Loop diuretics, remain a valid therapeutic alternative for relieving symptoms of overload.
Some authors advocate that diuretic infusion is superior to boluses since urinary output could be maintain easily
it is important to monitor electrolytes levels and also to assess acid-based status during therapy.
A recent comprehensive review have shown that torsemide and bumetanide have more favorable pharmacokinetic profiles than furosemide.
Extracorporeal therapies
Fluid overload refractory to medical therapy requires the use of extracorporeal therapies such as CRRT since critically ill patients often show hemodynamic instability and/or multiple organ dysfunctions.
The optimal RRT for patients with AKI and fluid overload has not been defined yet and there is still an ongoing debate. The choice based on the availability, expertise; the individual needs and hemodynamic status.
Conclusion:
Fluid overload has also been related to increased mortality.
The optimal assessment of volume status in critically ill patients is of vital importance.
Meticulous monitoring of fluid balance is critical for all patients
One key aspect of fluid overload management is to maintain hemodynamic stability and optimize organ function
Level of evidence : 5 narrative review.
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Ajay
Summarise this article
Introduction
Fluid overload is common in AKI patients in the CCU and is associated with adverse outcomes
Aim of the study: evaluation and management of fluid overload in the ICU
Discussion
The role of fluid therapy in the development of fluid overload
Appropriate fluid management requires knowledge of the pathophysiology, evaluation of volume status, selection of appropriate solution, and maintenance and modulation of the tissue perfusion
Consequences of fluid overload in organ systems are cerebral edema, myocardial edema, pulmonary edema, renal interstitial edema, hepatic congestion, gut edema, and tissue edema
Fluid overload and outcomes
There is a correlation between fluid overload and mortality in critically ill patients with ARDS, acute lung injury, sepsis, and AKI according to several studies
Fluid overload recognition and assessment
1. Daily fluid balance
2. Cumulative fluid balance
3. Fluid overload (pulmonary edema or peripheral edema)
4. Fluid accumulation
5. Percentage of fluid overload adjusted for body weight (A cutoff of ≥10 % has been associated with increased mortality)
% Fluid overload = ((total fluid in−total fluid out) /admission body weight * 100)
Fluid status assessment
History and physical examination
Chest x ray
Natriuretic peptides high levels of BNP (can be elevated in MI and PE). Has a high negative predictive value
Bioimpedance vector analysis detects soft tissue hydration
Thoracic ultrasound B-lines suggest thickened interstitial or fluid-filled alveoli
Vena cava diameter ultrasound
Normal diameter of IVC is 1.5 to 2.5 cm (measured 3 cm from the right atrium)
Volume depletion is when an IVC diameter <1.5 cm and IVC diameter >2.5 cm suggests volume overload
Fluid overload management
Diuretic therapy
Urine output of 3–4 ml/kg/h rarely causes intravascular volume depletion
Either bolus or using a continuous infusion
Electrolyte disturbances are common and need monitoring assessment of acid base balance
In patients with AKI the response to furosemide may be reduced due to reduced tubular secretion of furosemide and blunted response of Na-K-2Cl co-transporters at the loop of Henle (higher doses are needed with the risk of ototoxicity and myocardial dysfunction)
Extracorporeal therapies
In fluid overload refractory to medical therapy (CRRT/SCUF)
Conclusions
Fluid overload is associated with complications (CHF, pulmonary edema, delayed wound healing, tissue breakdown, and impaired bowel function) and increase mortality
It is important to assess the volume status early in critically ill patient
Loop diuretics are used to treat fluid overload in critically ill patients with fluid overload but diuretic resistance developed particularly in AKI
I liked reading your summary and analysis, Will you change your practice based on this article?
Ajay
-Background
Multiple studies empathised the association between fluid overload and mortality specially in critically ill patients.
Restrictive fluid therapy is suitable in ARDS and after major surgeries because it can decrease the duration of mechanical ventilation and the rate of cardiopulmonary complications .
Volume status evaluation is crucial particularly in critically ill patients .
Discussion
Fluid therapy role in the development of fluid
Overload
Achieving appropriate fluid therapy in critically ill patients is crucial meanwhile this achievement necessitate proper evaluation of the patient volume status, suitable solution for volume repletion, and maintenance of tissue perfusion.
The use of crystalloid as an initial therapy in patients at risk of AKI and with sepsis can increase the fluid overload incidence leading to impairment of tissue oxygenation and organ dysfunction.
Fluid overload and outcomes
Bouchard et al. mentioned that patients with fluid overload occurring with more than 10% increase in body weight is accompanied by higher incidence of respiratory failure , mechanical ventilation and sepsis .
AKI cases having fluid overload has high 30 and 60 day mortality also their renal recovery is much lower.
Multiple studies conducted on adults and paediatrics stated that accumulation of fluid detected on starting CCRT therapy was much lower in cases who survived.
Fluid overload can lead to pulmonary oedema or ARDS ,a study declared that cases with septic shock and ALI had lower hospitalisation mortality with conservative fluid therapy.
VASST study published that fluid overload therapy specially those with CVP> 12 mmHg are associated with increased mortality.
Fluid overload detection and evaluation
There is no standardization for documentation of intake and output, that is why it is highly variable therefore not reliable enough.
Suggestions were proposed to achieve standardization
including daily fluid balance excluding insensible water loss, cumulative fluid balance,fluid overload, fluid accumulation with or without fluid overload ,fluid overload % adjusted for body weight.
Most of methods used to evaluate fluid status are inaccurate involving
– History and physical signs of fluid overload in addition to basic investigations as chest xray which has a poor predictive value of volume overload , ECG ,BNP which seemed to be the most beneficial test as if it is high can correlate with volume overload but harbours falses as well because BNP level can increase with RF and decrease with obesity , low levels have higher negative predictive values and not higher levels.
– Bioimpedance vector analysis (BIVA) detects whole
body fluid volume and is dependent on patterns of the resistance-reactance graph, relating body impedance to body hydration
BIVA and CVP was compared in a study and concluded that both were in accordance with each other in the high CVP group(13-20 mmHg), moderate accordance in the medium CVP(4-12mmHg)group, and poor in low CVP group(0-3 mmHg).
Therefore combing both BIVA and CVP can represent a useful diagnostic tool for deciding for the fluid therapy specialy in cases with low CVP.
-Thoracic US
Agricola et al declared that PCWP correlated with the B-lines “comet-tail images”detected by thoracic US in patients with congestive heart failure.
-IVC diameter US
IVC diameter <1.5 cm can be indicative of volume depletion while an IVC diameter >2.5 cm indicates volume overload.
Lyon et al demonstrated appreciable difference between the IVCde before and after blood donation and between IVCdi before and after donation .
IVC d and right ventricule diameter assessment could be a non invasive method for evaluation of the fluid status and the response to fluid therapy in critically ill cases.
Treatment of fluid overload
Diuretics
Ultrafiltration is not superior till now on diuretics in treatment of overloaded cases with or without AKI regarding the AKI progression and overall outcomes.
Aggressive diuretic use can decrease fluid overload and outcome but at the same time carrier a risk of AKI.
A target of t a urine output of 3–4 ml/kg/h was suggested as it rarely causes hypovolemia.
A study demonstrated that diuretic infusion can be better as it can achieve better diuresis with higher urinary output meanwhile using smaller doses therefore avoiding the side effects.
On the other hand DOSE-AHF study stated that AHF cases can need bolus doses.
The treatment method either bolus of infusion is debatable.
Electrolyte monitoring is important due to high risk of electrolyte disturbance as hypokalaemia ,hypomagnesemia and hypochloremic metabolic alkalosis that need correction.
Torsemide and bumetanide were introduced as having better pharmacokinetic profiles than furosemide, but their effects are conflicting.
Higher doses of frusemide are needed in AKI due to the reduced response to frusemide ,leading to higher risk of side effects as ototoxicity and myocardial dysfunction.
Extracorporeal therapy
It is needed in refractory cases to medical therapy in critically ill patients with hemodynamic instability and organ dysfunction.
CRRT advantage over intermittent hemodialysis is that it removes the fluid slowly preserving hemodynamic stability as well as slow control of solute concentration avoiding cerebral oedema due to fluid shift.
Studies suggested that CRRT is an independent predictor of renal recovery among the surviving cases.
In critically ill patients with AKI and volume overload the use of CRRT or IHD depends on the patient needs and hemodynamic status.
SCUF is a type of CRRT done with low blood flow rates and low ultrafiltration rates.
CVVH provides continuous fluid ,electrolytes and toxin clearance.
The aim is preserving tissue perfusion, maximizing fluid balance by removal of fluid without decreasing the effective circulating volume, therefore, precise monitoring of fluid balance is mandatory .
Costanzo et al. found that patient treated with ultrafiltration experienced a longer time to recurrence of heart failure
, and fewer heart fail[1]ure and cardiovascular events.
Compared to cases treated with intravenous loop diuretics.
Conclusion
Fluid overload is associated with many complications as heart failure and even mortality.
Therefore assessment of fluid status is mandatory specially in critically ill cases.
The aim of fluid therapy is to preserve hemodynamic stability and organ functions.
Loop diuretic effectiveness is limited
RRT can be needed in management of fluid overload in critically ill patients.
-level of evidence is V
I liked reading your summary and analysis, Will you change your practice based on this article?
Ajay
VI. Fluid overload in the ICU – evaluation and management
——————————————————————————————————————-
Discussion
The role of fluid therapy in the development of fluid overload
Fluid overload and outcomes
Fluid overload recognition and assessmen
-Fluid overload percentage can be calculated using the following formula :
% Fluid overload ¼ total fluid in−total fluid out / addmmesiom body weight X 100
Fluid status assessment
History and physical examination:
Chest radiography
Natriuretic peptides
Bioimpedence vector analysis
Thoracic ultrasound
Vena cava diameter Ultrasound
Fluid overload management
Diuretic therapy:
Extracorporeal therapies
–Other advantages of CRRT over IHD include:-
Conclusions
What is the evidence provided by this article?
The evidence level is V
I liked reading your summary and analysis, Will you change your practice based on this article?
Ajay
Thank you very much Prof.Sharma
Yes, Prof.
SUMMARY
Introduction
One of the most important aspects of care in ICU is fluid management as this has a major role to play on how long a patient will remain on ventilator or even the outcome of the care. Recovery has been seen to be better and faster among patient with AKI but not fluid congested compared to those that are overload with fluid
Fluid overload and outcome
Assessment of fluid status
Fluid overload management
-CRRT – preferred
-IHD – not the idea for critically ill patient
Conclusion
Alot of severe complications including mortality has been attributed to fluid overload, hence optimal fluid management is key to survival of critically ill patient
The level of evidence is 5
Thank you
Fluid overload is commonly found in critically ill patients with AKI, it is associated with several adverse effects as peripheral edema, pulmonary edema and delayed wound healing.
The role of fluid therapy in development of fluid overload:
Adequate fluid resuscitation is essential in patients with septic and cardiogenic shock, initially, crystalloids are administered then distributed to extracellular volume due to increased capillary leak leading to fluid overload, impaired cell to cell interaction and progressive organ dysfunction especially kidney and liver.
Also, fluid overload occurs due to severe sepsis due to altered microcirculation.
Fluid overload and outcome:
Several studies suggested an association between fluid overload and mortality in critically ill patients, fluid overload was associated with difficulty in weaning from mechanical ventilation and more sepsis while conservative fluid management resulted in lower hospital mortality, improved oxygenation and shorter hospital stay
The VASST trial showed higher mortality rates in patients with fluid overload.
Fluid overload recognition and assessment:
Includes daily fluid balance, cumulative balance, fluid overload, fluid accumulation and percentage of fluid overload adjusted for body weight.
Fluid status assessment:
Most of tests are considered inaccurate.
History and physical examination:
History of heart failure and PNDs, signs as lower limb edema, jugular venous pressure.
Have variable sensitivity and specificities and should be combined with other measures.
Chest radiography:
Chest X-ray commonly used with limitations as absent signs of pulmonary congestion in some patients at time of diagnosis, portable X-ray have reduced sensitivity in supine patients.
Natriuretic peptide:
Increase in volume overload, MI and pulmonary embolism, may be lowered in obesity and may be increased in renal failure
Low BNP has negative predictive value for excluding heart failure.
Bioimpedence vector analysis:
Estimate body composition and soft tissue hydration, noninvasive and inexpensive.
Combined BIVA and CVP may improve clinical assessment and fluid therapy management.
Thoracic U/S:
Sonographic artifacts as B-lines suggest fluid filled alveoli and thickened interstitial
Vena cava diameter U/S:
IVC diameter and right ventricle diameter are practical and noninvasive, used in fluid state estimation.
Fluid overload management:
Diuretic therapy:
Alternative to ultrafiltration in AKI and congestive heart failure, no evidence suggesting better outcome with ultrafiltration than with diuretic therapy.
Although diuretic may increase risk of AKI, they are associated with more volume removal and better outcome.
Given as bolus or continuous infusion, infusion is associated with more response and less adverse effects in some studies.
May lead to hypokalemia, hypomagnesemia and hypochloremic metabolic alkalosis.
Torsemide and bumetanide are more favorable than frusemide.
Extracorporeal therapy:
used in fluid overload resistant to diuretic therapy, the optimal RRT in patients with AKI and overload is not well determined.
Modality is determined by available resources, local expertise and hemodynamic state.
CRRT maintain hemodynamic stability, better fluid balance control and avoid large fluid shift
CRRT and IHD can be used as complementary therapy according to hemodynamics.
Slow continuous ultrafiltration and continuous veno-enous hemofiltration are other types of CRRT.
The goal is to maintain tissue perfusion and removing fluid without affecting circulating fluid volume.
Aquadex FlexFlow system is a new small portable device for treatment of fluid overload.
Thankyou well done
Volume overload in critically ill patients is associated with higher incidence of mortality and complications including heart failure, pulmonary edema, delayed wound healing, GIT function impairment,
It was reported that in critically ill patients a 10 % increase in weight due to volume overload is associated with increase in the risk of respiratory distress, mechanical ventilation and mortality after 30 and 60 days
The use of IV fluids is represents an important cause of volume overloads and thus restrictive fluid management strategies are usually advised
Large proportion of crystalloids infused are distributed in the extravascular space with subsequent impairment of the diffusion of oxygen and metabolites and obstruction of capillary and lymphatic drainage of the tissues
The accurate assessment of volume status will help to minimize the gap between volume overload (associated with high mortality) and volume depletion (associated with organ hypoperfusion and AKI) and will also decrease the need for CRRT
Assessment of fluid status
A- History
B-Clinical assessment
C- Laboratory investigations
D- Radiological investigations
E- Cardiac assessment
F- Bioimpedance vector analysis
Management of fluid overload
Diuretics
Extracorporeal therapies
Well done
Thankyou
Welcome prof
Summary
This article has a central theme of evaluating and managing appropriately fluid overload in the ICU.
The occurrence of fluid overload in critically ill patients is significant because it can lead to pulmonary edema, cardiac failure, delayed wound healing, tissue breakdown, and impaired bowel function. This article focusses on understanding the background behind fluid overload and how fluid therapy can be sustainably maintained to avoid complications in the patient.
Fluid resuscitation is important to maintain good cardiac output, systemic BP and renal perfusion. However, with constant administration of crystalloid solutions as part of initial treatment for AKI patients, there can develop a leakage of IV fluids into the extravascular space, causing edema and fluid overload. Edema can occur from increased capillary permeability proteins, as well as increased hydrostatic pressure because of reduced pre capillary vasoconstriction.
This has several harmful effects like
Liver, lungs and kidneys are affected to the maximum from these effects. Renal recovery is lower in patients with fluid overload.
Fluid overload recognition and assessment needs recording of daily fluid balance, cumulative fluid balance, fluid overload, fluid accumulation, and percentage of fluid overload adjusted for body.
In terms of investigation,
Treatment options include
Level of evidence
This is a narrative review, hence level of evidence is 5.
Well done