yes and the recommendation from previous studies like early directed goal therapy should be revisited however in real life still CVP monitoring is widely used and after reading this systematic review i will change my practice
yes, we started to use non invasive parameters for assessment of volume status post operataive, however, unfortunately, intraoperative we still depend on CVP.
I think we might utilize that tool as on case by case setting, and it has to be considered in the context of other findings elicited by history,physical examination and other tools like stroke volume variation study and trans esophageal echo.
Introduction:
There are only a few clinical studies that compared the CVP guided fluid therapy with the other modern techniques and their relation to the outcome in renal transplantation.
This work sheds some light on the available published data in renal transplantation, together with data from other disciplines evaluating the utility of central venous pressure measurement.
Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status, therefore it’s value in fluid management of renal transplant recipient is at the best speculative. DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION:
CVP reading is affected by several physical and anatomical factors as:
Central venous blood volume:
Venous return/cardiac output, Total blood volume Regional vascular tone
Compliance of central compartment:
Vascular tone Right ventricular compliance, myocardial disease, pericardial disease Tamponade
Tricuspid valve disease:
Stenosis Regurgitation
Cardiac rhythm:
Junctional rhythm atrial fibrillation Atrio-ventricular dissociation.
Reference level of transducer:
Positioning of patient Intrathoracic pressure.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING: The introduction of equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in peri-operative fluid management.
TED.
Lithium dilution technology (e.g., LiDCOplusTM machine).
Arterial pulse wave analysis (e.g., FloTrac/VigileoTM). CONCLUSION:
Although CVP measurement continues to be popular, yet it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Alternative to CVP, we recommend using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipient.
LEVEL OF EVIDENCE V.
Rehab Fahmy
2 years ago
This article advice against use of CVP in deciding of IV fluid post kidney transplant as it can be affected by many factors and give false readings
in our practice although our routine protocol is still using CVP readings but we usually correlate CVP readings with clinical status of the patent (determining volume status by symptoms(is there any SOB ,orthopnea,dyspnea, vitals (O2 sat,BP,HR),chest exam:any fine creps ,LL edema ,I/O balance) and modify the protocol according to it .
Nasrin Esfandiar
2 years ago
As fluid therapy is important during kidney transplantation, the best technique to guide fluid therapy is changing from CVP to the new ones.
CVP reading could be affected by several factors.
Such as venous return, total body volume, vascular tone.
Myocardial or pericardial or tricuspid valve diseases, AF respiration, PPV, PEEP and pneumothorax.
Factors that influence CVP during surgery are:
1- position of the patient
2- abdominal retractors
3- PPV during surgery
4- there is no consensus about intra –operative CVP.
5- Fluctuation between over load and dry state in CKD patient and using β-block, CCBs or α-blockers is confounding.
6- CV stenosis due to CVP placement may affect dialysis vascular access in the future.
Possible alternative for fluid status monitoring are:
Dynamic preload variables like stroke volume variation (SVV) assessed by commercially available equipment are better choice for fluid management especially in peri-operative period.
Using trans esophageal Doppler (TED)intra operatively was associated with lower fluid overload
Use of SVV (by minimally invasive cardiac output monitoring was associated with improve patient outcomes.
Non-invasive techniques like lithium dilution technology or arterial pulse wave analysis are utilized, too.
Electrical bio impedance partial CO2 rebreathing and pulsed dye densitometry are the other techniques.
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based?Summarise this article
INTRODUCTION
The objective of this study to answer the question
in regards to clinical application of CVP and its benefits and limitation.
Many studies conducted that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status. The optimum fluid resuscitation is essential to maximise the outcomes in critically ill patients. HISTORICAL USE OF CVP
The clinical correlation between CVP and the intravascular fluid volume were established more than 50 years ago.
Marik et al published a systematic review article that evaluated the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management. DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
CVP is not the right tool in assessing the fluid balance and guide fluid therapy in renal transplantation.
CVP reading is affected by several physical and anatomical factors.
During kidney transplant operation, the recipient is
exposed to many intraoperative factors which may alter the CVP reading :
(1) During the operation, the position of the patient is not always in flat supine position.
(2) transplant surgery always entails the use of abdominal retractors and must have a pressure effect on the
viscera and subsequently affect the venous return.
(3) There is positive pressure ventilation (PPV) during the
transplant operation will affect the CVP reading.
(4) The target intra-operative CVP remains elusive.
While aggressive hydration ensures good allograft perfusion. However, over hydration carries the risk of pulmonary congestion, pulmonary oedema, and prolonged intubation.
(5) CKD patients on dialysis fluctuate between the volume overload state and the dry state during the post-dialysis period, which makes it difficult to declare which CVP reading should be considered as a normal reading.
(6)The placement of central venous catheters and other devices may result in central vein stenosis. POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
Srivastava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected
flow time and variation in stroke volume values.
They concluded that TED was associated with a similar rate of immediate graft function, a significantly less amount of intra-operative intravenous (IV) fluids, and reduced incidence of postoperative fluid overload.
Kumar et al studied the use of SVV to guide the perioperative fluid therapy in major abdominal surgery.
Lower amount of IV fluids used with the new technique, shorter ICU stay, and a non-significant shorter hospital stay.
Several other non-invasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology and arterial pulse wave analysis. CONCLUSION
CVP continues to be popular methods, however it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Large variations in intravascular volume status and the patients have limited range of intravascular volume. Pulmonary oedema could be the first sign of fluid overload.
The patient position, use of abdominal retractors, and the positive pressure ventilation make any CVP reading meaningless.
CVP measurement be abandoned in renal transplantation since it may be misleading.
Using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
What is the evidence provided by this article?
Level of evidence is level 5
Wael Jebur
2 years ago
central venous pressure CVP measurement is commonly utilized in everyday practice to assess volume status as its theoretically reflecting pressure in superior vena cava SVC and right atrium which is supposedly echoing preload pressure in right ventricle. This concept was challenged over years by several studies, that emphasized on different mechanisms can interfere with transducing the preload ventricular pressure to jugular veins through SVC .
Factors interfere with credibility of CVP include:
Tricuspid valve disease, stenosis and regurgitation. right ventricular failure and hypertrophy, pericardial disease and tamponade.
several factors might interfere with proper assessment of CVP, such as hypertension , aging, anti-hypertensive , vasodilators, and previous central venous cannulation , which could result in stenosis and fibrosis of the denoted veins.
The current non-invasive tools were proved to be more sensitive and specific in addressing cardiac output and pre-load.such trans esophageal echo TEE and stoke volume variation SVV and lithium dilution study.
In transplantation:
CVP is falling short of credibility due to several issues,
1) Positioning of the patient
2) Abdomen retractors.
3)Positive pressure ventilation.
Level of Evidence is 5
Rihab Elidrisi
2 years ago
In this article, Prof Halawa and other doctors try to reflect on the most suitable way to assess the volume status of a renal transplant recipient
A lot of centers depend on CVP to assess the volume status
Limitations of CVP use in renal transplantation:
There are many factors which affect CVP in renal transplantation including the position of the patient, which is not flat supine (essential for accurate CVP measurement), use of abdominal retractors (affect venous return due to pressure effects and intrathoracic pressure), the effect of positive pressure ventilation, non-standardization of target intra-operative CVP, non-availability of baseline CVP due to fluid fluctuations in dialysis patients, risk of central venous stenosis, and presence of various confounding factors like age, hypertension, and medications affecting the peripheral vascular resistance.
Conclusion:
CVP monitoring is the most extensively used modality for volume monitoring and fluid management, however, it has limitations. Novel cardiac output monitoring technologies can improve intraoperative and postoperative volume monitoring and fluid management. Physicians should be aware of their limitations. In the ward, frequent weighing and vital signs monitoring may better assess fluid status than CVP readings.
Mohamad Habli
2 years ago
Introduction: Central venous pressure (CVP) monitoring, used widely in ICUs to identify patients’ volume status, may be beneficial in cases of heart failure and volume depletion, but it has many limitations, so many other modalities have been studied to better evaluate volume status intra-operatively.
CVP measurement influences:
1. Venous return, cardiac output, total blood volume, regional vascular tone.
Tricuspid valve disorders.
3. Junctional rhythm, A-fib, etc.
Patient placement.
5. Intrathoracic pressure—respiratory fluctuations, pneumothorax, and mechanical ventilation.
6. Cardiovascular issues: vascular tone, myocardia/pericardial disorders, and Rt. Ventricular compliance.
CVP’s renal transplantation drawbacks:
Positive pressure ventilation during operation.
Retractors affect venous return.
CKD patients’ volume status might change from overload to dry, which may impact CVP measurements. Chronic medicines (alfa blockers, beta blockers, etc.) may influence peripheral vascular resistance.
When the renal transplant fails and the patient returns to dialysis, central vein stenosis may threaten the future of the ipsilateral arteriovenous fistula and graft.
Fluid monitoring alternatives:
Intra-operative trans-esophageal Doppler calculates adjusted flow time and stroke volume variations, improving volume status evaluation. Studies show even shorter ICU stays improve patient outcomes and recovery.
Lithium dilution by peripheral arterial lines permits continuous CO monitoring, however neuromuscular inhibiting medicines may influence it.
Electrical bio-impedance partial CO2 rebreathing: noninvasive, requires several mathematical assumptions, impacted by dysrhythmias, requires intubation and MV with minimal gas exchange settings.
Pulse dye densitometry: noninvasive, impacted by vasoconstriction, sensor movement, and interstitial edema.
Conclusion: CVP monitoring is the most extensively used modality for volume monitoring and fluid management, however it has limitations.
Novel cardiac output monitoring technologies can improve intraoperative and postoperative volume monitoring and fluid management. Physicians should be aware of their limitations.
In the ward, frequent weighing and vital signs monitoring may better assess fluid status than CVP readings.
Thank you professor for such a professional approach, I took lot of things to additions/ correct my program.
specially fluid management.
Mohammad Alshaikh
2 years ago
Summarise this article: Introduction: Central venous pressure (CVP) monitoring, used widely in ICU setting to identify volume status of the patients, it may be beneficial in cases of heart failure and volume depletion, but this would not be the case in intra-operative volume status evaluation because it has a lot of limitations, so many other modalities have been studied in this setting to better evaluate volume status. Factors affecting CVP measurement are: 1. Venous return, cardiac output, total blood volume, and regional vascular tone. 2. Tricuspid valve diseases. 3. Cardiac arrhythmias: junctional rhythm, A.fib,.. etc. 4. Positioning of the patient. 5. Intrathoracic pressure: respiratory variations, pneumothorax, and modalities of mechanical ventilation. 6. Cardiovascular issues: vascular tone, myocardia or pericardial diseases, and Rt. Ventricular compliance. Drawbacks and limitations of CVP in relation to renal transplantation: · Frequent positioning for better vascular approach. · Use of positive pressure ventilation during surgery. · The use of retractors may affect venous return. · CKD patients fluctuate in volume status from overload to dry and vice versa, which might affect the CVP readings. As well as the chronic medications used (Alfa blockers, beta blockers, ..etc.) may affect peripheral vascular resistant. · The placement of central line may result in central vein stenosis, that can jeopardise the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity when the renal graft fails, and the patient returns to dialysis. Alternatives for fluid status monitoring: – Intra-operative trans-esophageal Doppler: estimates the corrected flow time and the stroke volume variations, allows better intra-operative volume status evaluation. Studies show even less ICU stay, improves patient outcome, and enhance recovery. – Lithium dilution: by peripheral arterial lines, allows continuous CO monitoring, but may be affected by some neuromuscular blocking drugs. – Electrical bio-impedance partial CO2 rebreathing: noninvasive, requires a lot of mathematical assumptions, affected by dysrhythmias, requires intubation and MV with minimal gas exchange settings. – Pulse dye densitometry: noninvasive, affected by vasoconstriction, movement of the sensor, and interstitial edema. Conclusion: The CVP monitoring continued to be the most commonly used modality for volume monitoring guiding fluid management, but it is not ideal due to its limitations explained above. For better intraoperative and postoperative volume monitoring and fluid management, novel cardiac output monitoring devices, can be used, physicians should be familiar with, knowing their limitations. In the ward, frequent weighing, and vital signs monitoring may be better in evaluation of fluid status than CVP readings.
What is the evidence provided by this article? Level of evidence V, erratic review.
Manal Malik
2 years ago
summary of Utility of central venous pressure measurement in renal transplantation – Is it evidence based?Introduction:3
Several studies proved that CVP measurement are neither correlated to cardiac output nor have a precise correlation with intravascular volume. Aim of this review to answer the question in regard to clinical application of CVP and it is benefit and limitation. Drawback and limitation of CVP in relation to renal transplantation:
CVP is not a suitable tool in assessing the fluid balance Guide fluid therapy in renal transplantation:
As affecting several physical and anatomical factors:
1. During operation the patient is not always in flat supine position
2. Use of abdominal retractors by transplant surgeon
3. There is positive pressure ventilation (PPV) during the transplant operation
4. The target of intraoperative CVP remain exclusive
5. CKD patients on dialysis fluctuate between the volume overload state
6. Central venous stenosis due to previous catheterization Possible alternative for fluid status monitoring:
Interoperative transoesophageal doppler (TED): to estimate the corrected flow time and variation in stroke volume.
· TED associated with significant less amount of interoperative intravenous fluid and reduce of postoperative fluid overload
· Use of SVU to guide the perioperative fluid therapy in major abdominal surgery
· Treatment of IV fluid shorter ICU stay
· Other non-invasive technique are: Lithium dilution technology and arterial pulse === Conclusion:
CVP is not ideal for guiding and monitoring of fluid management in renal transplantation due to large variation in intervascular volume status and the patients have limited range of intravascular volume.
Factors made CVP cannot be relay on:
· Doubtful of fluid status balance
· Patient position, abdominal retraction and positive pressure ventilation make any CVP reading meaningless
· Alternative to CVP: intraoperative and postoperative cardiac output maintain devices for guiding fluid therapy in renal transplant recipient
2- evidence level 5
Mohamed Saad
2 years ago
Utility of central venous pressure measurement in renal transplantation: Is it evidence based? INTRODUCTION.
Fluid therapy post kidney transplant is an important issue because our patients may be have DGF with oliguria or polyuria of the recovery state.
Central venous catheter is one of the tools that used for assessing intravascular volume and affect our decision regarding fluid therapy for many years back, Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status. CVP IN RELATION TO RENAL TRANSPLANTATION.
Many factors intraoperative and post-operative can affect the accurate readings of CVP such as .
1-The effect of posture (on table during operation) changes on CVP reading .
2-Abdominal retractors have a pressure effect on the
viscera and will resist movement of the diaphragm and will eventually affect the intrathoracic pressure and these mechanical
factors will give a false CVP reading.
3-Positive pressure ventilation (PPV) during the transplant operation will affect the CVP.
4-Effect of ageing, long-standing hypertension and the
use of various medications affecting the peripheral vascular resistance (alpha blockers, beta blockers and calcium channel blockers) would be further confounding parameters.
5-Better to preserve central venous systems, for future access insertion for Hemodialysis. ALTERNATIVES FOR FLUID STATUS MONITORING.
=Trans esophageal Doppler (TED) to estimate the corrected
flow time and variation in stroke volume values, studies shown that TED associated with a significantly less amount of intra-operative intravenous(IV) fluids, and reduced incidence of postoperative fluid overload with the same rate of immediate
graft function.
=SVV (obtained from minimally invasive cardiac output monitor) to guide the perioperative fluid therapy in major
abdominal surgery has lower amount of IV fluids used with the new technique, not only that but also there was a significantly shorter ICU stay, and a non-significant shorter hospital stay.
=Other non -invasive methods as lithium dilution technology and arterial pulse wave analysis but each one has its limitations that should be clear to physician to chose the best modality. CONCLUSION.
Many studies shown that CVP affected by many factors intraoperative and factors related to patients medical condition which affects our decision regarding the fluid therapy post kidney transplant , so it not be more considered as a tool for intravascular volume assessment and better to be abandoned , using newer intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients is suggested but we should understand their limitations that help us to provide more robust monitoring
of fluid therapy.
Level of evidence 5
Amit Sharma
2 years ago
Summarise this article
Central venous pressure (CVP) has been used as a measure to guide fluid therapy, the adequacy of which is vital in kidney transplant recipients. CVP measures the pressure in superior vena cava or right atrium, which is a marker for right ventricular preload. Many studies have shown that CVP is not a reliable marker for assessing fluid status, but may be useful in certain situations like severe congestive heart failure or hypovolemia. CVP is still used very frequently for monitoring intravascular fluid status.
Limitations of CVP use in renal transplantation: There are many factors which affect CVP in renal transplantation including the position of the patient, which is not flat supine (essential for accurate CVP measurement), use of abdominal retractors (affect venous return due to pressure effects and intrathoracic pressure), effect of positive pressure ventilation, non-standardization of target intra-operative CVP, non-availability of baseline CVP due to fluid fluctuations in dialysis patients, risk of central venous stenosis, and presence of various confounding factors like age, hypertension, and medications affecting the peripheral vascular resistance.
Fluid status monitoring options: Dynamic preload variables like stroke volume variation (SVV) can be assessed using newer equipment like intraoperative transesophageal Doppler (TED). TED assesses corrected flow time and variation in stroke volume values and its use has been shown to be associated with reduced amount of intra-operative fluid used and decreased incidence of post-operative fluid overload. Minimally invasive cardiac output monitoring systems available include pulse wave analysis modality (FloTrac), lithium dilution technology (LiDCOplus), electrical bioimpedance, partial CO2 rebreathing, and oulsed dye densitometry. SVV obtained by using minimally invasive cardiac output monitor used to monitor perioperative fluid therapy has resulted in shorter ICU stay and hospital stay. Most of these monitoring devices require an arterial line and get affected by arrhythmias.
To conclude, it is suggested to abandon CVP measurement in renal transplantation in favor of intra-operative and post-operative cardiac output monitoring devices for guiding fluid management in renal transplantation in addition to monitoring vital signs including daily body weight.
2. What is the evidence provided by this article?
Level of evidence: Level 5 – Narrative review.
Huda Al-Taee
2 years ago
Summary:
Central venous pressure measurements have been in use for more than half a century to assess the intravascular fluid status of renal transplant recipients and, thereby, be used as a guide for intravenous fluid therapy in renal transplantation.
Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status. Therefore it’s value in fluid management of renal transplant recipients is at best speculative.
HISTORICAL USE OF CVP
The theoretical basis of CVP is to measure the pressure in the superior vena cava or right atrium pressure, which reflects the right ventricle preload.
The clinical correlation between CVP and the intravascular fluid volume were established more than 50 years ago.
DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
CVP reading is affected by several physical and anatomical factors.
During kidney transplant operation, the recipient is exposed to many intraoperative factors which may alter the CVP reading, hence, can be misleading in decision making, these factors are:
During the operation, the position of the patient is not always in flat supine position.
transplant surgery always entails the use of abdominal retractors. These retractors must have a pressure effect on the viscera and subsequently affect the venous return.
there is positive pressure ventilation during the transplant operation will affect the CVP reading.
the target intra-operative CVP remains elusive.
CKD patients on dialysis fluctuate between the volume overload state and the dry state during the post-dialysis period, which makes it difficult to declare which CVP reading should be considered as a normal reading.
placement of central venous catheters and other devices may result in central vein stenosis. Central vein stenosis can jeopardise the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity when the renal graft fails, and the patient returns to dialysis.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
The introduction of commercially available equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] is considered a revolutionary advance in peri-operative fluid management.
A study evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values. the outcome was compared with the historical records of the controls who received CVP-guided fluid management. They concluded that TED was associated with a similar rate of immediate graft function. Moreover, it was associated with a significantly less amount of intraoperative intravenous fluids, and reduced incidence of postoperative fluid overload.
A study about the use of SVV to guide perioperative fluid therapy in major abdominal surgery found a significantly lower amount of IV fluids used with this new technique, also there was a significantly shorter ICU stay, and a non-significant shorter hospital stay.
Several other non-invasive techniques are utilised for cardiac output assessment and IV fluid guidance, like lithium dilution technology and arterial pulse wave analysis, each one of these novels, non-invasive techniques has its own limitations.
Level of Evidence:
Level 5 (mini-review article).
Abhijit Patil
2 years ago
Summary
Introduction
CVP has been historically used to assess intravascular fluid status of renal transplant patient and guide fluid therapy
this study aimed to re-assess the role of CVP in fluid monitoring and objectively review its benefits and limitations.
Limitations of CVP
The authors strongly feel that CVP is not the right tool in assessing the fluid balance and guide fluid therapy in renal transplantation.
Several physical and anatomical factors affect it.
The intra-operative position especially head down and tilting of table affects the CVP reading.
Abdominal retractors during surgery cause pressure effect on the viscera and subsequently affect the venous return. It also restricts diaphragmatic movement and gives false CVP reading
Positive pressure ventilation during the transplant operation affects the CVP
the target intra-operative CVP remains elusive. there needs to be a balance between proper hydration and overhydration leading to pulmonary edema and cardiac conditions.
CVP may be affected by ageing, long-standing hypertension and the use of various medications affecting the peripheral vascular resistance (alpha blockers, beta blockers and calcium channel blockers)
CVP placement may lead to central vein stenosis which may jeopardise the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity.
Conclusion:
CVP is imprecise in predicting fluid volume status
Pulmonary oedema could be the first sign of fluid overload.
Other variables such as the patient position, the use of abdominal retractors, and the positive pressure ventilation make any CVP reading meaningless.
The authors conclude that CVP measurement be abandoned in renal transplantation
Alternative to CVP, there are various intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
Sir, we have also abandoned the use of CVP for fluid monitoring in general urology and kidney transplant patients.
Hussam Juda
2 years ago
· Many studies found that CVP measurements are not reliable to evaluate intravascular volume status
· Fluid resuscitation is important to maximise the outcomes in critically ill patients, but only a few studies have attempted to assess the role of CVP in comparison to other modern techniques in the field of renal transplantation
· Marik et al in his systematic review article concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management
· Cecconi et al found that CVP is unreliable guide to fluid resuscitation
· 89.2% of Canadian physicians still use CVP as a monitoring parameter in septic shock
· Bignami et al found that CVP was used most frequently for monitoring intravascular volume status after cardiac surgery in Italy
· During kidney transplant operation, the recipient is exposed to many intraoperative factors which may alter the CVP reading. These factors are:
1) patient posture according to the table direction
2) abdominal retractors have a pressure effect on the viscera and subsequently affect the venous return
3) positive pressure ventilation (PPV) during the transplant operation
4) the target intra-operative CVP still unknown
5) Fluctuation of hydration state in patients on dialysis during the post dialysis period
6) central vein stenosis due to previous central venous catheters
· Srivastava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values
· TED was associated with a similar rate of immediate graft function, but less amount of intra-operative (IV) fluids, and reduced incidence of postoperative fluid overload
· non-invasive techniques for cardiac output assessment and IV fluid guidance:
1) Pulse wave analysis (LiDCOrapid and FloTrac/Vigileo)
2) Lithium dilution (LiDCOplus)
3) Electrical bioimpedance (BioZ)
4) Partial CO2 rebreathing (NICO)
5) Pulsed dye densitometry (DDG-330)
CONCLUSION
· CVP measurement is not ideal guide for fluid management in renal transplantation.
· Pulmonary oedema could happen due to unreliability of CVP evaluation
· CVP measurement should be abandoned in renal transplantation since it may be misleading
· intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients are recommended
Level of evidence 5
Zahid Nabi
2 years ago
Fluid management is cornerstone of initial patient care of kidney transplant patients . How to guide this therapy is another area of debate. Central venous pressure (CVP) monitoring for years is considered as stanadard however current paper has resided serious questions on validity of CVP in this regard.
The authors have strongly challenged it.They suggest that central venous pressure (CVP) measurement should be abandoned in renal transplantation since it may be misleading. They recommend using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
The clinical correlation between CVP and the intra vascular fluid volume were established more than 50 years ago[. Theoretical basis of CVP is to measure the pressure in the superior vena cava (SVC) or right atrium pressure, which reflects the right ventricle pre load
Marik et al published a systematic review article that evaluated the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management. Similarly Cecconi et al pointed that commonly used preload measurements such as CVP or end diastolic volume, when used in isolation, cannot be used reliably as a guide to fluid resuscitation.
The article was published in 2018 and authors mentioned that 89% of Canadian physicians were using CVP as a guide to monitor fluid therapy reflecting the practicing style at that time.
According to authors one can not rely on CVP during transplant surgery for multiple reasons like
Changing position of patients
use of abdominal retractors
Positive pressure ventilation
Effect of antihypertensive affecting peripheral vascular resistance.
The introduction of commercially available equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in perioperative fluid management. Sriva stava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values. TED was used to guide intraoperative fluid management in 110 living donor renal transplant recipients, and the outcome was compared with the historical records of 104 control recipients who received CVP guided fluid management over the previous year. They concluded that TED was associated with a similar rate of immediate graft function. Moreover, it was associated with a significantly less amount of intraoperative intr avenous (IV) fluids, and reduced incidence of posto perative fluid overload.
Similarly, Kumar et al studied the use of SVV (obtained from minimally invasive cardiac output mo nitor) to guide the perioperative fluid therapy in major abdominal surgery. Furthermore, several other noninvasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM)[19,20]. However, each one of these novel, noninvasive techniques has its own limitations.
CONCLUSION.
The authors concluded by saying that As clearly evident from the data we suggest that CVP measurement be abandoned in renal transplantation since it may be misleading. Alternative to CVP, we re commend using intraoperative and postoperative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
Assafi Mohammed
2 years ago
Summary of the article “Utility of central venous pressure measurement in renal transplantation – Is it evidence based?”
Factors affecting the measured CVP readings:the measured central venous pressure readin
1. Central venous blood volume
· Venous return/cardiac output
· Total blood volume
· Regional vascular tone
2. Compliance of central compartment
· Vascular tone
· Right ventricular compliance:
§ Myocardial disease
§ Pericardial disease
§ Tamponade
3. Tricuspid valve disease
· Stenosis
· Regurgitation
4. Cardiac rhythm
· Junctional rhythm
· Atrial fibrillation
· Atrio-ventricular dissociation
5. Reference level of transducer
· Positioning of patient; the patient is not always in flat supine position.
6. Intrathoracic pressure
· Respiration
· Intermittent positive pressure ventilation
· Positive end-expiratory pressure
· Tension pneumothorax
Alternatives to CVP measurement in assessing the volume status:
Commercially available equipment for assessing dynamic preload variables:
· Stroke volume variation (SVV) using transesophageal Doppler (TED).
· Minimally invasive cardiac output monitoring devices:
§ Pulse wave analysis
§ Lithium dilution CO
§ Electrical bioimpedance
§ Partial CO2 rebreathing
§ Pulsed dye densitometry
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 8; CVP use in KT Summary
· CVP was used for decades as an indicator of the volume status, need for fluid resuscitation and response to fluid resuscitation therapy.
· However, many studies concluded that it is not reliable tool to assess the volume status. Instead, combination of many clinical and none invasive tools can be utilized to assess the volume status.
· CVP is not the ideal assessment tool in kidney transplant recipients as it is affected by many factors as ventricular compliance, vascular tone, presence of any arrhythmia, any valvular lesion, pericardial or myocardial disease, position of the patient and transducer, intrathoracic pressure which is affected by mechanical ventilation.
· Assessment of volume status in transplant patient is crucial as hypovolemia impairs the graft perfusion and over-hydration leads to pulmonary edema and prolonged hospitalization.
· Causes of inappropriateness of CVP Intraoperative:
o table tilt affects the readings as the patient not lie flat.
o Pressure of retractors affects the intra-abdominal pressure,
o Swing in vascular tone in those patients with use of vasodilator anti-hypertensives as ccb, alpha and beta blockers.
o Use of CVC itself carries a risk of central vein stenosis and precludes ipsilateral AVF creation.
· New available tools for assessment of volume status:
o Intraoperative trans-esophageal Doppler to measure SVV (stroke volume variability), had similar outcome as regard graft function with less risk of fluid overload than CVP guided fluid therapy, with less ICU stay and rapid recovery.
o In conclusion, new available methods as pulse wave analysis and lithium dilution technology have their own limitations and should be used on individual bases.
Level of evidence: level V (narrative review)
saja Mohammed
2 years ago
This review article was published in chest journal an impact factor of10.26 .
SUMMARY
This article reviews the data from previous research between 1966=2007 addressing the value of CVP to guide IVF management in critically ill patients, by a systematic review of all studies from midline PubMed, Cochrane
CVP central venous is referred to the pressure measured in the right atrium or SVC and its thoughts its correlated to intravascular volume and can help in estimating the intravascular fluid and blood depletion it’s used for assessment of fluid management in critically ill patients in ICU, ER and intraoperative however the evidence of such practice been tested by a systematic review of previous studies which support such practice.
According to this systematic review of 24 studies that fit the inclusion criteria all failed to show any correlation between the CVP and the volume status, none of these studies took into consideration the positive end-expiratory pressure levels or changes in intrathoracic pressure account when measuring the CVP, the rt ventricular filling does not depend on CVP only we need the transmural rt atrial pressure gradient which in reality barely calculated
By principle, the only reason to challenge patients with volume is to increase the stroke volume, and once the starling law reached the even level (plateau) at this stage continuing the given volume will do harm and lead to interstitial edema with tissue hypoxemia so it’s important during resuscitation to assess the patient for fluid responsiveness or not.
CVP measurement can mislead the calculation of the IVF replacement and increase the risk of volume overload and pulmonary edema in sepsis, ICU critical patients, and intraoperative which is associated with higher mortality, the fact that CVP is not ideal to reflect the vascular volume status and can be misleading tool have been studied a long time ago by many observational studies back to 1970s, however, after this systematic review the CVP should not be used for ICU, intraoperative and in an emergency as a tool to guide IVF replacement and should be still used in selection post-cardiac surgery and PE in order to assess the RT ventricular filling, not the volume status.
alternative suggestion includes intra and post-operative cardiac output monitoring devices and not CVP monitoring in kidney transplant candidates .
Strength of this review
1. Demanding selection criteria used to identify relevant studies
2. the use of quantitative endpoints
3. The studies are outstanding for the consistency
(Both in magnitude and direction) of their findings which point to the true findings
What is the evidence provided by this article?
Level of evidence 5, a narrative systematic review of observational studies no RCT
KAMAL YOUSIF ELGORASHI ADAM
2 years ago
Summary of the article; In the CPV was used for halve century , as guide for fluid status in renal transplantation. In present with advances in tools measuring and assessing fluid status, CVP was obsolete and prooved that neither it indicate cardiac stroke volume, nor intravascular volume. Marik et al,; Found that CVP is not realiable indicator for fluid ststus. Cecconi et al,;
CVP can not be reabily used as guide fluid status. A survey study in Canadian physician found that 89% of them use CVP as guidance in septic shock. Bignami et al.; Questionare dine in 77 centers in Italy found that CVP used frequently as fluid guidance, by 26% followed by Arterial blood pressure 19% and Echo 5.6%.
Sendergaard et al.; CVP was not though guide Preload, use to assess fluid load, cardiac performance and vascular resistance. During transplant operation, recipient exposed to many intraoperative factors that alter the CVP reading, thesefactors are;
The position of the patient is not always the flat supine position.
The operation use abdominal retractors, that may affect abdominal viscera and venous return, so affect accuracy of CVP reading.
There is a positive ventilator pressure that affect CVP.
The traget intraoperative CVP is elusive.
Variation of CVP as CKD patient on dialysis varies between overload and dry weight so accurate target to built on is unclear.
Many drugs and AHM affect BP and make misleading in assessing right CVP.
Central venous catheter may affect lumen of the veins and may cause stenosis and thrombosis.
Possible alternative for fluid measurement;
SVV, Stroke Volume Variation.
TED, intraoperative transoesophageal doppler.
Conclusion;
Although CVP use to have still popular, it is not reliable in assessing fluid status.
There may be large variation in real fluid status, for which patient can considered euvolemic while many factors can affect CVP; Drugs, Atherosclerosis, Stenosis, Aging.
CVP during transplantation is misleading and should not be relaible on.
Level of evidence ((V))
Ghalia sawaf
2 years ago
only a few studies have reliably to assess the role of CVP in comparison to other modern techniques in the field of renal transplantation.
This study aims to answer this question in regards to clinical application of CVP
Marik et al published a systematic review article concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management.
Cecconi et al pointed that commonly used preload measurements such as CVP or end diastolic volume, when used in isolation, cannot be used reliably as a guide to fluid resuscitation.
the study validated the role of CVP in certain situations as severe congestive heart failure or hypovolemia, where the use of CVP is valuable in guiding fluid managemen
Bignami et al analyzed data collected from 71 centers for monitoring intravascular volume status, CVP was used most frequently (26.7%), followed by arterial BP (19.7%) and echocardiography (5.6%)
Sondergaard et al reported that CVP, though not a direct measure of preload, can be used to assess volume status, heart performance and systemic vascular resistance.
LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
CVP reading is affected by several physical and anatomical factors
During kidney transplant operation, the recipient is exposed to many intraoperative factors which may alter the CVP reading, hence, can be misleading in decision
These factors can be summarized in the following points:
(1) During the operation, the position of the patient is not always inflat supine position.
The effect of posture changes on CVP reading was documented since a long time
(2) transplant surgery always entails the use of abdominal retractors. These retractors must have a pressure effect on the viscera and subsequently affect the venous return
(3) (PPV) during the transplant operation will affect the CVP reading
(4) The target intraoperative CVP remains elusive.
aggressive hydration ensures good allograft pe rfusion. On the other hand, overhydration carries the risk of pulmonary congestion, pulmonary oedema
(5) the effect of ageing, longstanding hypertension and the use of various medications affecting the peripheral vascular resistance
(6) place ment of central venous catheters and other devices may result in central vein stenosis.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
The introduction of stroke volume variation (SVV)] considered a revolutionary advance in perioperative fluid management.
Sriva stava et al evaluated the use of intraoperative (TED)
TED was used to guide intraoperative fluid management in 110 living donor renal transplant recipients, and the outcome was compared with the historical records of 104 control recipients who received CVP guided fluid management over the previous year.
They concluded that TED was associated with a similar rate of imm ediate graft function.
with a significantly less amount of intraoperative (IV) fluids, and reduced incidence of postoperative fluid overload
Kumar et al studied the use of SVV to guide the perioperative fluid therapy in major abdominal surgery.
The study documented a significantly lower amount of IV fluids used with the new technique,
not only that but also there was a significantly shorter ICU stay,
and a nonsignificant shorter hospital stay
Several other noninvasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM
each one of these novel, noninvasive techniques has its own limitations
Lithium dilution LiDCOplus™ advantages
Simple technique (can use peripheral arterial line);
Continuous CO monitoring
Disadvantages
Arterial line required;
Accuracy affected by some neuromuscular blocking drugs;
Lithium chloride is contraindicated in patients undergoing treatment with lithium salts
Pulse wave analysis
LiDCOrapid™ and FloTrac/Vigileo™ Advantages
Requires only arterial line;
Beat-by-beat CO monitoring (this may help to evaluate response to IV fluids).
– Validated by clinical studies in different medical and surgical conditions
Disadvantages
Presence of arterial line with optimum waveform signal is a prerequisite;
Accuracy may be reduced by sever arrhythmia;
Needs frequent recalibration during periods of hemodynamic Instability
Level 5
This level of evidence doesn’t have the power of evidence to change of practice we need more and more studies
Last edited 2 years ago by Ghalia sawaf
Eusha Ansary
2 years ago
Summary:
Adequate intravenous fluid therapy is essential in renal transplant recipients to ensure a good allograft perfusion. Central venous pressure (CVP) has been considered the cornerstone to guide the fluid therapy for decades; it was the only available simple tool worldwide. However, the revolutionary advances in assessing the dynamic preload variables together with the availability of new equipment to precisely measure the effect of intravenous fluids on the cardiac output had created a question mark on the future role of CVP.
The introduction of commercially available equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in peri-operative fluid management. The use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values.
TED was used to guide intraoperative fluid management in 110 living donor renal transplant recipients, and the outcome was compared with the historical records of 104 control recipients who received CVP guided fluid management over the previous year. They concluded that TED was associated with a similar rate of immediate graft function. Moreover, it was associated with a significantly less amount of intra-operative intravenous (IV) fluids, and reduced incidence of postoperative fluid overload.
Furthermore, several other non-invasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM).
Although CVP measurement continues to be popular, yet it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Level of evidence 5
Hadeel Badawi
2 years ago
CVP has been used to guide fluid therapy in therapy in kidney transplantation. Several studies showed that CVP correlates poorly with cardiac output or intravascular volume. The utility of CVP measurement in KT
needs further evaluation.
It is not the best tool for assessing and guiding fluid therapy in renal transplantation as It is affected by several physical and anatomical factors.
Drawbacks and limitations of CVP in relation to renal transplantation:
– The effect of posture changes on CVP reading, as the patient is not always in a flat supine position.
– The use of abdominal retractors affects intrabdominal and intrathoracic pressure, affecting venous return.
– PPV during the transplant operation will affect the CVP reading.
– The target of intra-operative CVP is not yet identified.
– Fluctuation of CKD patients’ fluid status make the CVP target difficult.
– The effect of ageing, long-standing hypertension, and medications would be confounding.
– Consider the risk of central vein stenosis when using a central device.
A possible alternative for fluid status monitoring: –Intraoperative transesophageal Doppler (TED).
-lithium dilution technology.
-Arterial pulse wave analysis
– Electrical bio-impedance Partial CO2 rebreathing.
– Pulsed dye densitometry
Several trials investigated the reliability of these new techniques to guide fluid therapy in surgical cases.
Conclusion:
Due to several limitations, CVP is not ideal for guiding and monitoring fluid management in renal transplantation. Using output monitoring devices combined with other hemodynamic variables for patient evaluation and management is recommended in KT
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based? 1. Summarise this article History
CVP for assessment of intravascular fluid volume is in use for >50 years; it measures pressure in the SVC or RA, & thus reflects RV preload.
Marik et al: said CVP is not a reliable indicator of fluid status & should not be used to guide fluid management.
Marik et al (meta-analysis): abandoned use of CVP as a guide in fluid management.
Cecconi et al: CVP or end diastolic volume can’t reliably guide fluid resuscitation; >1 hemodynamic variable recommended. Current practice Canada:
89.2% of physicians use CVP monitoring in septic shock.
78.7% of clinicians consider CVP defined endpoints as the end-point of volume resuscitation in early septic shock. Italy (Bignami et al): after cardiac surgery, CVP used most frequently (26.7%); arterial BP (19.7%) & echo-cardiography (5.6%).
Sondergaard et al: CVP used to assess volume status, heart performance & systemic vascular resistance. CVP in KTX
CVP reading is affected by:
1.Position of the patient (not always flat supine during surgery).
2.Abdominal retractors have a pressure effect on the viscera & thus affect the venous return.
3.The PPV during the TX operation will affect the CVP.
4.Ageing
5.Long-standing HTN
6.Medications affecting the peripheral vascular resistance (α-blockers, β-blockers & CCBs)
7.Fluctuation between the volume overload state
& the dry state during the post-dialysis period. Commercial tools for assessing fluid management:
1.Intra-op TED (Srivastava et al, 110 LKD KTRs): outcome comparable to the historical records of 104 control recipients who received CVP guided fluid management over the previous year.
2.Kumar et al: use of SVV (obtained from minimally invasive cardiac output monitor): the new technique was associated with:
– lower amount of IV fluids
– shorter ICU stay
– shorter hospital stay (non-significant)
3.Lithium dilution technology (e.g., LiDCO plusTM machine) & arterial pulse wave analysis (e.g., FloTrac /Vigileo TM):
Each has its own limitations. Conclusion
CVP measurement is not ideal for guiding fluid management in KTRs.
The large variations in intravascular volume status will render reliance on CVP imprecise; pulmonary edema could be the 1stsign of fluid overload.
The patient position, the use of retractors, & the PPV make any CVP reading meaningless.
The authors suggest that CVP measurement be abandoned in KTX because it may be misleading.
The authors recommend, as an alternative to CVP, using intra-op & post-op cardiac output monitoring devices for guiding fluid therapy in KTRs. ///////////////////////////////// 2.What is the evidence provided by this article? Level V
-Introduction
Multiple studies concluded that CVP does not correlate with intravascular volume nor valid as a guide for fluid therapy.
Fluid resuscitation is crucial in critically ill patients, which directly affect the outcome. CVP historical use
Marik et al stated that CVP is not an indicator of fluid status and must be abandoned as a guide for fluid management.
Cecconi et al adviced using multiple hemodynamic variables together for better evaluation of the volume status and highlighted the CVP utility in certain cases for fluid therapy guidance as in CHF and hypovolemia. CVP in current practice
CVP remains the base of clinical practice as noted in a survey done in Canada and still in use as declared by other studies . Limitations of CVP in renal transplantation
CVP is affected by multiple factors as central venous blood volume , compliance of central compartment as positive pressure ventilation (PPV) during the
transplant operation can affect the CVP ,heart rhythms , tricuspid valve diseases, the reference transducer level as CVP is variable with different positioning and retractors used intraoperative can affect the venous return and can affect the intrathoracic pressure as well as ageing , long standing hypertension and the use of drugs affecting peripheral vascular resistance therefore CVP can mislead decision making of fluid therapy in renal transplantation.
Targeted intraoperative CVP is unknown , in the postdialysis period the CVP is fluctuating for the patients so it is difficult to know the normal CVP reading.
Central venous stenosis is a complication of central venous catheter introduction which can negatively affect AV fistula or graft needed to be done on the same limb if the patient needed dialysis in a later stage. Alternatives for fluid staus monitoring
Srivastava et al published that TED correlated with immediate graft function, TED use was associated with a significantly less amount of intra-operative IV fluids, and less incidence of postoperative fluid overload.
Kumar et al stated that stroke volume velocity decreased the amount of IV perioperative fluid used as well as ICU stay.
Lithium dilution technology and arterial pulse wave analysis are noninvasive methods used for assessment of cardiac output and guide IV fluid therapy.
Each one of those methods have it’s limitations and advantages.
For example pulse wave analysis advantage are only requiring arterial line,CO monitoring beat by beat ,but drawbacks is that arrhythmia can reduce it’s accuracy.
Lithium dilution is a simple method but is affected by neuromuscular blocking drugs.
Pulse dye densitometry is non invasive but it’s assessment is intermittent and hemodynamic instability affects it’s accuracy. Conclusion
CVP continues to be the most popular method used although it was proved that it is not reliable for fluid assessment nor for guidance of fluid therapy.
CVP is affected by multiple factors rendering it an unreliable method to monitor or navigate fluid management in renal transplantation.
Intra-operative and post-operative cardiac output monitoring devices are adviced for guiding fluid therapy in renal transplant recipients instead of CVP.
For ward monitoring regular vital signs monitoring is recommended as daily body weight.
-Level of evidence is V
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based?
Summarise this article
What is the evidence provided by this article?
——————————————————————————————————————-
Central venous pressure (CVP) measurement century to assess in travascular fluid status of renal transplant recipients intravenous fluid therapy in renal transplantation.
The study concluded CVP is an unreliable indicator of the fluid status and hence it would be unwise to use it as a guide to fluid management. Cecconi et al published a study that concluded that using CVP or end diastolic volume in isolation is not a reliable guide to fluid resuscitation.
CVP can be used for certain conditions, for example in severe congestive heart failure or hypovolemia.
Theoretical basis of CVP is to measure the pressure in the superior vena cava (SVC) or right atrium pressure, which reflects the right ventricle pre load.
Drawbacks and limitations to the use of CVP in kidney transplantation
These factors can be summarised in the fol lowing points:
During the operation, the position of the patient is not always in flat supine position.
Transplant surgery always entails the use of abdominal retractors.)
There is positive pressure ventilation (PPV) during the transplant operation will affect the CVP reading .
The target intra operative CVP remains elusive.
. On the other hand, overhydration carries the risk of pulmonary congestion, pulmonary oedema, and prolonged intubation especially in patients with pre existing cardiac conditions.
CKD patients on dialysis fluctuate between the volume overload state and the dry state during the post dialysis period, which makes it difficult .
Should not forget that placement of central venous catheters and other devices may result in central vein stenosis.
Alternative tools to CVP in monitoring of fluid status
Evaluated the use of intraoperative transesophageal Doppler (TED).
Several other non invasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology.
Arterial pulse wave analysis.
Electrical bioimpedance.
Partial co2 rebreathing.
Pulse wave densitometry.
Conclusion
CVP measurement continues to be popular,yet it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Other alternative devices should be used in renal transplantation for guiding fluid therapy (intraoperative and postoperative cardiac output monitoring devices).
Understanding their limitations helps to provide more robust monitoring of fluid therapy.
Introduction
The assessment of intravascular fluid status either in the ICU or during surgeries has rested solely on the use of central venous pressure for over half of the century, but the narrative is gradually changing due to more recent ways of measurement of CVP and also the outcome of some studies against its reliability. However, some studies validated the use of CVP for fluid management in some situation, but it uses in kidney transplantation has not been helpful and this is part of what this article is set out to answer.
Drawbacks and limitations to the use of CVP in kidney transplantation
patients during the surgery are not always in supine position
the use of abdominal retractor will affect the diaphragmatic movement
presence of positive pressure ventilation during kidney transplant
no known intraoperative target CVP during kidney transplantation
fluctuation in fluid status of CKD patients
CVP line can cause vascular stenosis
Alternative tools to CVP in monitoring of fluid status
transesophageal doppler
lithium dilution technology
arterial pulse wave analysis
electrical bioimpedance
partial co2 rebreathing
pulse wave densitometry
Conclusion
CVPstill has a growing popularity, but this is not enough to certify it as a reliable tool to measure fluid status particularly during kidney transplantation surgery as it has been shown to be with a lot of drawbacks and limitations which can also affect the successful outcome of the procedure.
Introduction
Central venous pressure (CVP) measurements have been used to assess intravascular fluid status of patients, especially renal transplant recipients. Some studies have shown that CVP measurements do not correlate with cardiac output and the intravascular volume status. The study is aimed to objectively assess the validity of using CVP measurements in renal transplant patients.
In theory, CVP measurements involve the measure of the pressure in the superior vena cava (SVC) or the pressure in the right atrium – these reflect the right ventricle preload.
Marik et al published a systematic review which evaluated the relationship between CVP and the fluid status of the patient. The study concluded CVP is an unreliable indicator of the fluid status and hence it would be unwise to use it as a guide to fluid management.
Cecconi et al published a study that concluded that using CVP or end diastolic volume in isolation is not a reliable guide to fluid resuscitation. However, CVP can be used for certain conditions, for example in severe congestive heart failure or hypovolemia.
Data collected from Italy and Canada indicated that clinicians prefer to use CVP measurements for monitoring intravascular fluid status, followed by arterial BP and echocardiography.
Drawbacks and limitations of CVP in relation to renal transplantation:
Availability of modern medical advances have altered the approach of assessing intravascular fluid status.
CVP readings are affected by several factors, such as:
Central venous blood volume
Venous return/cardiac output
Total blood volume
Regional vascular tone
Compliance of central compartment
Vascular tone
Myocardial disease
Pericardial disease
Tamponade
Tricuspid valve disease
Stenosis
Regurgitation
Cardiac rhythm
Junctional rhythm
Atrial fibrillation
Atrio-ventricular dissociation
Reference level of transducer
Positioning of the patient
Intrathoracic pressure
Respiration
Intermittent positive pressure ventilation
Positive end-expiratory pressure
Tension pneumothorax
Intraoperatively, CVP measurements can also be altered:
Position of the patient
Use of abdominal retractors – affects venous return due to the pressure on the viscera
Positive pressure ventilation during the operation
No definitive target CVP intra-operatively
CKD patients on dialysis have fluctuating fluid status, hence it is difficult to determine the ideal CVP for them
There is also the increased risk of central vein stenosis.
Possible alternatives for fluid status monitoring
Pulse wave analysis
Requires an arterial line
Validated by clinical studies in different medical and surgical conditions
Optimum waveform is required
Lithium dilution
Peripheral arterial line
Continuous CO2 monitoring
Accuracy is affected by some neuromuscular blocking medications
Electrical bio-impedance
Non-invasive
Limited validity in patients with arrhythmias
Partial CO2 rebreathing
Requires the patient to be intubated and on mechanical ventilation
Affected by hemodynamic instability
Pulsed dye densitometry
Non-invasive
Affected by movement of sensor, vasoconstriction and interstitial edema.
ConclusionCVP is shown to be the popular option amongst clinicians. However, the readings may be misleading, as many factors affect the measurement. Understanding the limitations of the cardiac output monitoring devices will help us better utilize them for more robust monitoring of fluid status in renal transplant patients. It is recommended not to use the CVP to guide fluid management in renal transplant patients
Level of evidence is Level V
CVP measurement is commonly used to assess fluid status and guide fluid therapy in kidney transplant recipients.
It is used to determine resuscitation goals, however several studies showed no correlation between CVP measurement and intravascular volume. Historical use of CVP:
It was used to correlate with intravascular fluid volume and volume status of the patients as it measure pressure in right atrium that reflect the right ventricle preload.
A systemic review and meta analysis showed CVP was indicating fluid status and shouldn’t guide fluid management.
CVP also was not reliable when used alone. CVP in the current practice:
It is very popular in clinical practice, in resuscitation practices, it is used for monitoring in septic shock and determine the endpoint of fluid resuscitation.
After cardiac surgery, It is the most commonly used method for hemodynamic monitoring. Drawbacks and limitations of CVP in relation to renal transplantation:
The measurement is affected by several physiological and anatomical factors including:
The position of patient during surgery which is usually not flat supine and is commonly head down.
Presence of abdominal retractors which increase intrathoracic pressure.
Positive pressure ventilation during surgery
Targeted intraoperative CVP is not determined due to the fluctuation between dry state and fluid overload state in patients or hemodialysis.
Long standing HTN and use of medications affecting peripheral vascular resistance.
Insertion of central venous catheter may cause central vein stenosis which may cause difficulty in performing arteriovenous graft or fistulas.
Possible alternatives for fluid status monitoring:
Intraoperative transesophageal doppler: guide fluid management and was associated with similar rate of intraoperative IV fluids with reduced post operative fluid overload.
Minimally invasive cardiac output measurement assessing stroke volume variation was associated with lower amount of IV fluids and significantly shorter ICU stay
Noninvasive tools are used as part of enhanced recovery programs.
Lithium dilution technology and arterial pulse wave analysis are recent and non invasive but with several limitations. Clinician should choose the modality according to each clinical scenario individually Conclusion:
It is suggested that CVP shouldn’t be used in kidney transplant recipients as it may be misleading.
Cardiac output monitoring devices are recommended to be used intra and post operative, while in ward, regular monitoring of vital signs and daily body weight can be used.
Optimum fluid resuscitation is essential to maximise the outcomes in critically ill patients
Although CVP have been used for a long time, it is correlated to cardiac output and intravascular volume status
CVP
Historical use
Marik et al studied the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management
Cecconi et al recommended that CVP should not be used alone for evaluation and management unless in severe CHF or hypovolemia
CVP in the current practice
CVP still used in most clinical practice. For example, in Canada 89.2% of physicians use CVP in septic shock
Limitations in renal transplantation
CVP is not the ideal tool of measurement of fluid balance. It is affected by several factors:
1. Central venous blood volume
2. Compliance of central compartment
3. Tricuspid valve disease
4. Cardiac rhythm
5. Reference level of transducer (postion of the patient)
6. Intrathoracic pressure
Intraoperative factors that change the CVP reading:
1. The position of the patient is not always in flat supine position
2. Use of abdominal retractors (reduce venous return by pressing the viscera)
3. Positive pressure ventilation (PPV )
4. No intraoperative exact target of CVP
5. Determination of the normal CVP is difficult in dialysis patient
6. Central vein stenosis
7. Ageing, longstanding HTN and the use of medications affecting the peripheral vascular resistance (alpha blockers, beta blockers and calcium channel blockers)
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
1. Intraoperative transesophageal Doppler (TED). When compared with CVP, TED was associated with a similar rate of immediate graft function and significant less amount of intraoperative intravenous fluids, and reduced incidence of postoperative fluid overload
CVP is not ideal for guiding fluid therapy in renal transplantation
Intraoperative factors like position and refractors affect the CVP
Other alternative devices should be used in renal transplantation for guiding fluid therapy (intraoperative and postoperative cardiac output monitoring devices)
Since the 1960s, central venous pressure (CVP) has been used to monitor intravascular fluid status in renal transplant patients and guide intravenous fluid management. With diagnostic tool advancements, CVP’s utility is debatable. Several investigations showed that CVP measures are not connected to cardiac output nor intravascular volume status, hence its utility in fluid management of renal transplant recipients remains questionable.
Current CVP measurement :
CVP assessment is important in clinical practice. 89.2% of Canadian doctors utilize CVP to monitor septic shock. 78.7% of Canadian doctors considered CVP endpoints the end-point of volume resuscitation in early septic shock.
LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION:
–During kidney transplant surgery, intraoperative variables may change CVP.
-Patient isn’t always supine throughout the surgery.
-Transplants need abdominal retractors. These retractors will alter visceral pressure and venous return.
-Positive pressure ventilation (PPV) affects CVP during transplant surgery.
-the target intra-operative CVP remains elusive.
-CKD patients on dialysis oscillate between volume overload and dry state post-dialysis, making it difficult to determine a normal CVP measurement.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING:
–Pulse wave analysis:limitation: The presence of an arterial line with optimum waveform signal is a prerequisite.
-Intraoperative trans-esophageal Doppler (TED): to measure flow time and stroke volume (SVV). It reduced intra-op IV fluids and post-op fluid overload.
-Lithium dilution: Some neuromuscular blocking medicines impact accuracy; lithium chloride is contraindicated for lithium salt patients.
-CONCLUSION
CVP measurement remains popular, although it’s not suitable for renal transplant fluid management.
We advocate intra- and post-operative cardiac output monitoring devices to guide fluid treatment in renal transplant patients. Knowing their limits improves fluid treatment monitoring.
CVP measures the pressure in the SVC or the right atrium pressure, which reflects the right ventricle preload. It is assumed to provide a reliable information about the patients circulatory and volume status. Studies showed that CVP is an unreliable indicator of the fluid status and some authors suggested abandoning the use of CVP as a guide in fluid management, while others reported that it can be used to assess volume status, heart performance, and systemic vascular resistance. Factors affecting the CVP reading during kidney transplant operation:
· Position of the patient as the operating table may be tilted during surgery,
· Pressure and tension of abdominal retractors,
· Positive pressure ventilation,
· Difficulty in determining the normal CVP of a CKD patient on dialysis,
· The risk of damage to central veins during catheterization, which may affect future dialysis access. Alternatives to CVP measurement in renal transplant:
· Intraoperative trans-esophageal Doppler (TED): to estimate the corrected flow time and variation in stroke volume values(SVV). it was associated with a decreased amount of intra-op IV fluids, decreased incidence of postop fluid overload.
· SVV: from minimally invasive cardiac output monitor, to guide the peri-op IVF fluid replacement in major abdominal surgery. It helps lower the amount of IVF, offers shorter ICU stay, and a non-significant shorter hospital stay.
· Lithium dilution technology: e.g., LiDCOplusTM machine, and
· Arterial pulse wave analysis.
This is a review (level of evidence V) evaluating the rule of CVP in assessment of fluid status in renal transplantation in comparison to the recent dynamic monitoring strategies and they suggest the following:
A- CVP should not be used for assessment of fluid status in renal transplantation due to the following :
Accurate CVP measurement needs putting he patient in the flat supine position which is not feasible sometimes intraoporetively since the surgeon may elevate the left or right side of the patients for better exploration of iliac vessels more over the head of the patient may be tilted down
CVP measurement can be affected by the use of retractors with subsequent pressure over the organs (increasing the venous return) and over the diaphragm (increasing the intrathoracic pressure)
The use of PPV during operation will increase intrathoracic pressure and can falsely increase he CVP
ESRD patients on hemodialysis have no baseline CVP reading since they fluctuate between volume depletion and volume overload
CVP reading can be affected by the variation in SVR which is affected by age, long standing hypertension, beta, alpha and calcium channel blockers
Central vein stenosis can occur due to placement of CVP which can affect the vascular access later on if the graft fail
Measure only the right atrial pressure and not the blood volume
CVP can be affected by any cardiac condition that increase the right atrial pressure
CVP insertion is associated with increase in the risk of infection since these patients are immunocompromised
B- Fluid therapy can be guided using cardiac output monitoring devices
Assessment of stroke volume variation using TEE provide excellent guide for fluid therapy intraoperatively and was associated with lower incidence of fluid overload post operatively
The use of TEE is not suitable for awake patients, so can be used only intraoperatively
Other methods can be used but they have several limitations including pulse wave analysis, lithium dilution, electrical bioimpedance Partial CO2 rebreathing and pulsed dye densitometry
Summary : Utility of central venous pressure measurement in renal transplantation – is it evidence based?
This study is about CVP measurement in renal transplant and its efficacy and place in improving transplant outcome for the graft and patient.
CVP has been used to guide fluid therapy in transplant patients. However, the authors of this study recommend avoiding CVP measurement as it can mislead the transplant team in terms of fluid resuscitation. In particular, even changes in patient position influence CVP reading, making it highly unreliable as a single marker for action.
titled table position during surgery can change CVP reading in comparison with the patient lying flat in supine position.
abdominal retractors used during the surgery can increase pressure on viscera and affect venous return influencing and altering CVP reading. In addition, the tension created by the retractors could possibly affect intrathoracic pressure giving a false CVP reading.
PPV during serge could again change CVP reading.
Fluctuation in the fluid status of CKD patients makes it difficult to zero in on one particular CVP reading as the only accurate or correct value.
Alternatively, intraoperative and postoperative cardiac output monitoring devices are recommended to be used. Regular monitoring of vital signs along with daily body weight measurement has been seen to be useful in recognizing harmful changes in the patient, allowing space for immediate action and early treatment. This can bring about a better outcome than manipulation of fluids based on CVP readings alone.
These devices that can be used as alternatives to CVP for fluid status monitoring include intraoperative TED or transedophageal doppler, SVV, lithium dilution technology and arterial pulse waves analysis. Each of these techniques has limitations but their advantages warrant their use.
Level of evidence
This article is a narrative review, hence level of evidence is 5.
Definitely, considering the fluctuation of CVP because it is influenced by multiple factors. Like the article mentions, a combination of different factors need to be considered in guiding fluid management appropriately in critically ill patients so that we do not ignore possible dehydration and at the same time avoid fluid overload and the host of complications that come along with it such as pulmonary edema.
Ban Mezher
2 years ago
CVP used for >50 years for intravascular fluid status in renal transplant recipients to guide IV fluid administration.
Several studies proved that CVP was not correlated with COP or intravascular fluid volume.
Theoretically CVP reflect SVC or right atrial pressure.
Both Marik et al & Cecconi et al studies show that cVP is not dependable method for intravascular fluid volume assessment.
Recently CVP still used in septic shock & during major cardiac surgery.
CVP reading can be affected by :
central venous blood volume.
compliance of central compartment.
tricuspid valve disease.
cardiac arrhythmia.
reference level of transducer
intra-thoracic pressure.
During transplant surgery several factors can alter CVP reading:
Patient position.
Using of abdominal retracts which can change venous return & retracted can limit diaphragm movement leading to increased intra-thoracic pressure.
PPV.
Intravascular volume fluctuation between overload before dialysis & dry state after dialysis.
Target intra-operative CVP remain difficult.
Central vein stenosis due to central vein catheter .
Alternatives to CVP for intravascular volume assessment:
SVV.
TED
Lithium dilution technology.
Arterial pulse wave analysis.
Advantages & limitations of these non invasive methods should be considered in chosen the best method.
Fluid management is critical in transplantation to guarantee adequate perfusion of the allogarft
Central venous pressure(CVP) has been used for longtime to monitor fluid management in transplantation but it is not accurate, may be affected by patient position, use of abdominal retractors and positive pressure ventilation. Therefore, it is misleading and it is use should be prohibited in kidney transplantation.
The utilization of the intra-operative and postoperative cardiac output monitoring devices is a better option than CVP in managing fluid therapy in renal transplantation.
In the ward continuous check of the vital signs including daily weight is better than CVP.
Thank you
Will you change your practice based on this article?
In this article, it was explained clearly that the CVP reading during transplantation is always NOT accurate.
Yes as CVP is proved not to be a reliable indicator of volume status nor guidance for fluid therapy
Yes, Dr Doaa.
Ajay
yes and the recommendation from previous studies like early directed goal therapy should be revisited however in real life still CVP monitoring is widely used and after reading this systematic review i will change my practice
yes, we started to use non invasive parameters for assessment of volume status post operataive, however, unfortunately, intraoperative we still depend on CVP.
I do not rely on CVP measurement.
Yes, CVP has its own drawbacks and limitations.
We do not use CVP measurement for fluid assessment in our transplant unit
yes ,will change my practise regarding use of CVP as indicator of volume status
I think we might utilize that tool as on case by case setting, and it has to be considered in the context of other findings elicited by history,physical examination and other tools like stroke volume variation study and trans esophageal echo.
Yes, we don’t relay on CVP for fluid management.
Introduction:
There are only a few clinical studies that compared the CVP guided fluid therapy with the other modern techniques and their relation to the outcome in renal transplantation.
This work sheds some light on the available published data in renal transplantation, together with data from other disciplines evaluating the utility of central venous pressure measurement.
Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status, therefore it’s value in fluid management of renal transplant recipient is at the best speculative.
DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION:
CVP reading is affected by several physical and anatomical factors as:
Central venous blood volume:
Venous return/cardiac output, Total blood volume Regional vascular tone
Compliance of central compartment:
Vascular tone Right ventricular compliance, myocardial disease, pericardial disease Tamponade
Tricuspid valve disease:
Stenosis Regurgitation
Cardiac rhythm:
Junctional rhythm atrial fibrillation Atrio-ventricular dissociation.
Reference level of transducer:
Positioning of patient Intrathoracic pressure.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING:
The introduction of equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in peri-operative fluid management.
TED.
Lithium dilution technology (e.g., LiDCOplusTM machine).
Arterial pulse wave analysis (e.g., FloTrac/VigileoTM).
CONCLUSION:
Although CVP measurement continues to be popular, yet it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Alternative to CVP, we recommend using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipient.
LEVEL OF EVIDENCE V.
This article advice against use of CVP in deciding of IV fluid post kidney transplant as it can be affected by many factors and give false readings
in our practice although our routine protocol is still using CVP readings but we usually correlate CVP readings with clinical status of the patent (determining volume status by symptoms(is there any SOB ,orthopnea,dyspnea, vitals (O2 sat,BP,HR),chest exam:any fine creps ,LL edema ,I/O balance) and modify the protocol according to it .
As fluid therapy is important during kidney transplantation, the best technique to guide fluid therapy is changing from CVP to the new ones.
CVP reading could be affected by several factors.
Such as venous return, total body volume, vascular tone.
Myocardial or pericardial or tricuspid valve diseases, AF respiration, PPV, PEEP and pneumothorax.
Factors that influence CVP during surgery are:
1- position of the patient
2- abdominal retractors
3- PPV during surgery
4- there is no consensus about intra –operative CVP.
5- Fluctuation between over load and dry state in CKD patient and using β-block, CCBs or α-blockers is confounding.
6- CV stenosis due to CVP placement may affect dialysis vascular access in the future.
Possible alternative for fluid status monitoring are:
Dynamic preload variables like stroke volume variation (SVV) assessed by commercially available equipment are better choice for fluid management especially in peri-operative period.
Using trans esophageal Doppler (TED)intra operatively was associated with lower fluid overload
Use of SVV (by minimally invasive cardiac output monitoring was associated with improve patient outcomes.
Non-invasive techniques like lithium dilution technology or arterial pulse wave analysis are utilized, too.
Electrical bio impedance partial CO2 rebreathing and pulsed dye densitometry are the other techniques.
The level of evidence is 5.
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based?Summarise this article
INTRODUCTION
The objective of this study to answer the question
in regards to clinical application of CVP and its benefits and limitation.
Many studies conducted that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status. The optimum fluid resuscitation is essential to maximise the outcomes in critically ill patients.
HISTORICAL USE OF CVP
The clinical correlation between CVP and the intravascular fluid volume were established more than 50 years ago.
Marik et al published a systematic review article that evaluated the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management.
DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
CVP is not the right tool in assessing the fluid balance and guide fluid therapy in renal transplantation.
CVP reading is affected by several physical and anatomical factors.
During kidney transplant operation, the recipient is
exposed to many intraoperative factors which may alter the CVP reading :
(1) During the operation, the position of the patient is not always in flat supine position.
(2) transplant surgery always entails the use of abdominal retractors and must have a pressure effect on the
viscera and subsequently affect the venous return.
(3) There is positive pressure ventilation (PPV) during the
transplant operation will affect the CVP reading.
(4) The target intra-operative CVP remains elusive.
While aggressive hydration ensures good allograft perfusion. However, over hydration carries the risk of pulmonary congestion, pulmonary oedema, and prolonged intubation.
(5) CKD patients on dialysis fluctuate between the volume overload state and the dry state during the post-dialysis period, which makes it difficult to declare which CVP reading should be considered as a normal reading.
(6)The placement of central venous catheters and other devices may result in central vein stenosis.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
Srivastava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected
flow time and variation in stroke volume values.
They concluded that TED was associated with a similar rate of immediate graft function, a significantly less amount of intra-operative intravenous (IV) fluids, and reduced incidence of postoperative fluid overload.
Kumar et al studied the use of SVV to guide the perioperative fluid therapy in major abdominal surgery.
Lower amount of IV fluids used with the new technique, shorter ICU stay, and a non-significant shorter hospital stay.
Several other non-invasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology and arterial pulse wave analysis.
CONCLUSION
CVP continues to be popular methods, however it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Large variations in intravascular volume status and the patients have limited range of intravascular volume. Pulmonary oedema could be the first sign of fluid overload.
The patient position, use of abdominal retractors, and the positive pressure ventilation make any CVP reading meaningless.
CVP measurement be abandoned in renal transplantation since it may be misleading.
Using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
What is the evidence provided by this article?
Level of evidence is level 5
central venous pressure CVP measurement is commonly utilized in everyday practice to assess volume status as its theoretically reflecting pressure in superior vena cava SVC and right atrium which is supposedly echoing preload pressure in right ventricle. This concept was challenged over years by several studies, that emphasized on different mechanisms can interfere with transducing the preload ventricular pressure to jugular veins through SVC .
Factors interfere with credibility of CVP include:
Tricuspid valve disease, stenosis and regurgitation. right ventricular failure and hypertrophy, pericardial disease and tamponade.
several factors might interfere with proper assessment of CVP, such as hypertension , aging, anti-hypertensive , vasodilators, and previous central venous cannulation , which could result in stenosis and fibrosis of the denoted veins.
The current non-invasive tools were proved to be more sensitive and specific in addressing cardiac output and pre-load.such trans esophageal echo TEE and stoke volume variation SVV and lithium dilution study.
In transplantation:
CVP is falling short of credibility due to several issues,
1) Positioning of the patient
2) Abdomen retractors.
3)Positive pressure ventilation.
Level of Evidence is 5
In this article, Prof Halawa and other doctors try to reflect on the most suitable way to assess the volume status of a renal transplant recipient
A lot of centers depend on CVP to assess the volume status
Limitations of CVP use in renal transplantation:
There are many factors which affect CVP in renal transplantation including the position of the patient, which is not flat supine (essential for accurate CVP measurement), use of abdominal retractors (affect venous return due to pressure effects and intrathoracic pressure), the effect of positive pressure ventilation, non-standardization of target intra-operative CVP, non-availability of baseline CVP due to fluid fluctuations in dialysis patients, risk of central venous stenosis, and presence of various confounding factors like age, hypertension, and medications affecting the peripheral vascular resistance.
Conclusion:
CVP monitoring is the most extensively used modality for volume monitoring and fluid management, however, it has limitations.
Novel cardiac output monitoring technologies can improve intraoperative and postoperative volume monitoring and fluid management. Physicians should be aware of their limitations.
In the ward, frequent weighing and vital signs monitoring may better assess fluid status than CVP readings.
Introduction: Central venous pressure (CVP) monitoring, used widely in ICUs to identify patients’ volume status, may be beneficial in cases of heart failure and volume depletion, but it has many limitations, so many other modalities have been studied to better evaluate volume status intra-operatively.
CVP measurement influences:
1. Venous return, cardiac output, total blood volume, regional vascular tone.
Tricuspid valve disorders.
3. Junctional rhythm, A-fib, etc.
Patient placement.
5. Intrathoracic pressure—respiratory fluctuations, pneumothorax, and mechanical ventilation.
6. Cardiovascular issues: vascular tone, myocardia/pericardial disorders, and Rt. Ventricular compliance.
CVP’s renal transplantation drawbacks:
Positive pressure ventilation during operation.
Retractors affect venous return.
CKD patients’ volume status might change from overload to dry, which may impact CVP measurements. Chronic medicines (alfa blockers, beta blockers, etc.) may influence peripheral vascular resistance.
When the renal transplant fails and the patient returns to dialysis, central vein stenosis may threaten the future of the ipsilateral arteriovenous fistula and graft.
Fluid monitoring alternatives:
Intra-operative trans-esophageal Doppler calculates adjusted flow time and stroke volume variations, improving volume status evaluation. Studies show even shorter ICU stays improve patient outcomes and recovery.
Lithium dilution by peripheral arterial lines permits continuous CO monitoring, however neuromuscular inhibiting medicines may influence it.
Electrical bio-impedance partial CO2 rebreathing: noninvasive, requires several mathematical assumptions, impacted by dysrhythmias, requires intubation and MV with minimal gas exchange settings.
Pulse dye densitometry: noninvasive, impacted by vasoconstriction, sensor movement, and interstitial edema.
Conclusion: CVP monitoring is the most extensively used modality for volume monitoring and fluid management, however it has limitations.
Novel cardiac output monitoring technologies can improve intraoperative and postoperative volume monitoring and fluid management. Physicians should be aware of their limitations.
In the ward, frequent weighing and vital signs monitoring may better assess fluid status than CVP readings.
Thank you professor for such a professional approach, I took lot of things to additions/ correct my program.
specially fluid management.
Summarise this article:
Introduction:
Central venous pressure (CVP) monitoring, used widely in ICU setting to identify volume status of the patients, it may be beneficial in cases of heart failure and volume depletion, but this would not be the case in intra-operative volume status evaluation because it has a lot of limitations, so many other modalities have been studied in this setting to better evaluate volume status.
Factors affecting CVP measurement are:
1. Venous return, cardiac output, total blood volume, and regional vascular tone.
2. Tricuspid valve diseases.
3. Cardiac arrhythmias: junctional rhythm, A.fib,.. etc.
4. Positioning of the patient.
5. Intrathoracic pressure: respiratory variations, pneumothorax, and modalities of mechanical ventilation.
6. Cardiovascular issues: vascular tone, myocardia or pericardial diseases, and Rt. Ventricular compliance.
Drawbacks and limitations of CVP in relation to renal transplantation:
· Frequent positioning for better vascular approach.
· Use of positive pressure ventilation during surgery.
· The use of retractors may affect venous return.
· CKD patients fluctuate in volume status from overload to dry and vice versa, which might affect the CVP readings. As well as the chronic medications used (Alfa blockers, beta blockers, ..etc.) may affect peripheral vascular resistant.
· The placement of central line may result in central vein stenosis, that can jeopardise the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity when the renal graft fails, and the patient returns to dialysis.
Alternatives for fluid status monitoring:
– Intra-operative trans-esophageal Doppler: estimates the corrected flow time and the stroke volume variations, allows better intra-operative volume status evaluation. Studies show even less ICU stay, improves patient outcome, and enhance recovery.
– Lithium dilution: by peripheral arterial lines, allows continuous CO monitoring, but may be affected by some neuromuscular blocking drugs.
– Electrical bio-impedance partial CO2 rebreathing: noninvasive, requires a lot of mathematical assumptions, affected by dysrhythmias, requires intubation and MV with minimal gas exchange settings.
– Pulse dye densitometry: noninvasive, affected by vasoconstriction, movement of the sensor, and interstitial edema.
Conclusion:
The CVP monitoring continued to be the most commonly used modality for volume monitoring guiding fluid management, but it is not ideal due to its limitations explained above.
For better intraoperative and postoperative volume monitoring and fluid management, novel cardiac output monitoring devices, can be used, physicians should be familiar with, knowing their limitations.
In the ward, frequent weighing, and vital signs monitoring may be better in evaluation of fluid status than CVP readings.
What is the evidence provided by this article?
Level of evidence V, erratic review.
summary of Utility of central venous pressure measurement in renal transplantation – Is it evidence based?Introduction:3
Several studies proved that CVP measurement are neither correlated to cardiac output nor have a precise correlation with intravascular volume. Aim of this review to answer the question in regard to clinical application of CVP and it is benefit and limitation.
Drawback and limitation of CVP in relation to renal transplantation:
CVP is not a suitable tool in assessing the fluid balance
Guide fluid therapy in renal transplantation:
As affecting several physical and anatomical factors:
1. During operation the patient is not always in flat supine position
2. Use of abdominal retractors by transplant surgeon
3. There is positive pressure ventilation (PPV) during the transplant operation
4. The target of intraoperative CVP remain exclusive
5. CKD patients on dialysis fluctuate between the volume overload state
6. Central venous stenosis due to previous catheterization
Possible alternative for fluid status monitoring:
Interoperative transoesophageal doppler (TED): to estimate the corrected flow time and variation in stroke volume.
· TED associated with significant less amount of interoperative intravenous fluid and reduce of postoperative fluid overload
· Use of SVU to guide the perioperative fluid therapy in major abdominal surgery
· Treatment of IV fluid shorter ICU stay
· Other non-invasive technique are: Lithium dilution technology and arterial pulse ===
Conclusion:
CVP is not ideal for guiding and monitoring of fluid management in renal transplantation due to large variation in intervascular volume status and the patients have limited range of intravascular volume.
Factors made CVP cannot be relay on:
· Doubtful of fluid status balance
· Patient position, abdominal retraction and positive pressure ventilation make any CVP reading meaningless
· Alternative to CVP: intraoperative and postoperative cardiac output maintain devices for guiding fluid therapy in renal transplant recipient
2- evidence level 5
Utility of central venous pressure measurement in renal
transplantation: Is it evidence based?
INTRODUCTION.
Fluid therapy post kidney transplant is an important issue because our patients may be have DGF with oliguria or polyuria of the recovery state.
Central venous catheter is one of the tools that used for assessing intravascular volume and affect our decision regarding fluid therapy for many years back, Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status.
CVP IN RELATION TO RENAL
TRANSPLANTATION.
Many factors intraoperative and post-operative can affect the accurate readings of CVP such as .
1-The effect of posture (on table during operation) changes on CVP reading .
2-Abdominal retractors have a pressure effect on the
viscera and will resist movement of the diaphragm and will eventually affect the intrathoracic pressure and these mechanical
factors will give a false CVP reading.
3-Positive pressure ventilation (PPV) during the transplant operation will affect the CVP.
4-Effect of ageing, long-standing hypertension and the
use of various medications affecting the peripheral vascular resistance (alpha blockers, beta blockers and calcium channel blockers) would be further confounding parameters.
5-Better to preserve central venous systems, for future access insertion for Hemodialysis.
ALTERNATIVES FOR FLUID
STATUS MONITORING.
=Trans esophageal Doppler (TED) to estimate the corrected
flow time and variation in stroke volume values, studies shown that TED associated with a significantly less amount of intra-operative intravenous(IV) fluids, and reduced incidence of postoperative fluid overload with the same rate of immediate
graft function.
=SVV (obtained from minimally invasive cardiac output monitor) to guide the perioperative fluid therapy in major
abdominal surgery has lower amount of IV fluids used with the new technique, not only that but also there was a significantly shorter ICU stay, and a non-significant shorter hospital stay.
=Other non -invasive methods as lithium dilution technology and arterial pulse wave analysis but each one has its limitations that should be clear to physician to chose the best modality.
CONCLUSION.
Many studies shown that CVP affected by many factors intraoperative and factors related to patients medical condition which affects our decision regarding the fluid therapy post kidney transplant , so it not be more considered as a tool for intravascular volume assessment and better to be abandoned , using newer intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients is suggested but we should understand their limitations that help us to provide more robust monitoring
of fluid therapy.
Level of evidence 5
Central venous pressure (CVP) has been used as a measure to guide fluid therapy, the adequacy of which is vital in kidney transplant recipients. CVP measures the pressure in superior vena cava or right atrium, which is a marker for right ventricular preload. Many studies have shown that CVP is not a reliable marker for assessing fluid status, but may be useful in certain situations like severe congestive heart failure or hypovolemia. CVP is still used very frequently for monitoring intravascular fluid status.
Limitations of CVP use in renal transplantation: There are many factors which affect CVP in renal transplantation including the position of the patient, which is not flat supine (essential for accurate CVP measurement), use of abdominal retractors (affect venous return due to pressure effects and intrathoracic pressure), effect of positive pressure ventilation, non-standardization of target intra-operative CVP, non-availability of baseline CVP due to fluid fluctuations in dialysis patients, risk of central venous stenosis, and presence of various confounding factors like age, hypertension, and medications affecting the peripheral vascular resistance.
Fluid status monitoring options: Dynamic preload variables like stroke volume variation (SVV) can be assessed using newer equipment like intraoperative transesophageal Doppler (TED). TED assesses corrected flow time and variation in stroke volume values and its use has been shown to be associated with reduced amount of intra-operative fluid used and decreased incidence of post-operative fluid overload. Minimally invasive cardiac output monitoring systems available include pulse wave analysis modality (FloTrac), lithium dilution technology (LiDCOplus), electrical bioimpedance, partial CO2 rebreathing, and oulsed dye densitometry. SVV obtained by using minimally invasive cardiac output monitor used to monitor perioperative fluid therapy has resulted in shorter ICU stay and hospital stay. Most of these monitoring devices require an arterial line and get affected by arrhythmias.
To conclude, it is suggested to abandon CVP measurement in renal transplantation in favor of intra-operative and post-operative cardiac output monitoring devices for guiding fluid management in renal transplantation in addition to monitoring vital signs including daily body weight.
2. What is the evidence provided by this article?
Level of evidence: Level 5 – Narrative review.
Summary:
Central venous pressure measurements have been in use for more than half a century to assess the intravascular fluid status of renal transplant recipients and, thereby, be used as a guide for intravenous fluid therapy in renal transplantation.
Several studies proved that CVP measurements are neither correlated to cardiac output nor have a precise correlation with intravascular volume status. Therefore it’s value in fluid management of renal transplant recipients is at best speculative.
HISTORICAL USE OF CVP
The theoretical basis of CVP is to measure the pressure in the superior vena cava or right atrium pressure, which reflects the right ventricle preload.
The clinical correlation between CVP and the intravascular fluid volume were established more than 50 years ago.
DRAWBACKS AND LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
Level of Evidence:
Level 5 (mini-review article).
Summary
Introduction
CVP has been historically used to assess intravascular fluid status of renal transplant patient and guide fluid therapy
this study aimed to re-assess the role of CVP in fluid monitoring and objectively review its benefits and limitations.
Limitations of CVP
The authors strongly feel that CVP is not the right tool in assessing the fluid balance and guide fluid therapy in renal transplantation.
Several physical and anatomical factors affect it.
Conclusion:
Sir, we have also abandoned the use of CVP for fluid monitoring in general urology and kidney transplant patients.
· Many studies found that CVP measurements are not reliable to evaluate intravascular volume status
· Fluid resuscitation is important to maximise the outcomes in critically ill patients, but only a few studies have attempted to assess the role of CVP in comparison to other modern techniques in the field of renal transplantation
· Marik et al in his systematic review article concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management
· Cecconi et al found that CVP is unreliable guide to fluid resuscitation
· 89.2% of Canadian physicians still use CVP as a monitoring parameter in septic shock
· Bignami et al found that CVP was used most frequently for monitoring intravascular volume status after cardiac surgery in Italy
· During kidney transplant operation, the recipient is exposed to many intraoperative factors which may alter the CVP reading. These factors are:
1) patient posture according to the table direction
2) abdominal retractors have a pressure effect on the viscera and subsequently affect the venous return
3) positive pressure ventilation (PPV) during the transplant operation
4) the target intra-operative CVP still unknown
5) Fluctuation of hydration state in patients on dialysis during the post dialysis period
6) central vein stenosis due to previous central venous catheters
· Srivastava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values
· TED was associated with a similar rate of immediate graft function, but less amount of intra-operative (IV) fluids, and reduced incidence of postoperative fluid overload
· non-invasive techniques for cardiac output assessment and IV fluid guidance:
1) Pulse wave analysis (LiDCOrapid and FloTrac/Vigileo)
2) Lithium dilution (LiDCOplus)
3) Electrical bioimpedance (BioZ)
4) Partial CO2 rebreathing (NICO)
5) Pulsed dye densitometry (DDG-330)
CONCLUSION
· CVP measurement is not ideal guide for fluid management in renal transplantation.
· Pulmonary oedema could happen due to unreliability of CVP evaluation
· CVP measurement should be abandoned in renal transplantation since it may be misleading
· intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients are recommended
Level of evidence 5
Fluid management is cornerstone of initial patient care of kidney transplant patients . How to guide this therapy is another area of debate. Central venous pressure (CVP) monitoring for years is considered as stanadard however current paper has resided serious questions on validity of CVP in this regard.
The authors have strongly challenged it.They suggest that central venous pressure (CVP) measurement should be abandoned in renal transplantation since it may be misleading. They recommend using intra-operative and post-operative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
The clinical correlation between CVP and the intra vascular fluid volume were established more than 50 years ago[. Theoretical basis of CVP is to measure the pressure in the superior vena cava (SVC) or right atrium pressure, which reflects the right ventricle pre load
Marik et al published a systematic review article that evaluated the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management. Similarly Cecconi et al pointed that commonly used preload measurements such as CVP or end diastolic volume, when used in isolation, cannot be used reliably as a guide to fluid resuscitation.
The article was published in 2018 and authors mentioned that 89% of Canadian physicians were using CVP as a guide to monitor fluid therapy reflecting the practicing style at that time.
According to authors one can not rely on CVP during transplant surgery for multiple reasons like
Changing position of patients
use of abdominal retractors
Positive pressure ventilation
Effect of antihypertensive affecting peripheral vascular resistance.
The introduction of commercially available equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in perioperative fluid management. Sriva stava et al evaluated the use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values. TED was used to guide intraoperative fluid management in 110 living donor renal transplant recipients, and the outcome was compared with the historical records of 104 control recipients who received CVP guided fluid management over the previous year. They concluded that TED was associated with a similar rate of immediate graft function. Moreover, it was associated with a significantly less amount of intraoperative intr avenous (IV) fluids, and reduced incidence of posto perative fluid overload.
Similarly, Kumar et al studied the use of SVV (obtained from minimally invasive cardiac output mo nitor) to guide the perioperative fluid therapy in major abdominal surgery. Furthermore, several other noninvasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM)[19,20]. However, each one of these novel, noninvasive techniques has its own limitations.
CONCLUSION.
The authors concluded by saying that As clearly evident from the data we suggest that CVP measurement be abandoned in renal transplantation since it may be misleading. Alternative to CVP, we re commend using intraoperative and postoperative cardiac output monitoring devices for guiding fluid therapy in renal transplant recipients.
Summary of the article
“Utility of central venous pressure measurement in renal transplantation – Is it evidence based?”
Factors affecting the measured CVP readings:the measured central venous pressure readin
1. Central venous blood volume
· Venous return/cardiac output
· Total blood volume
· Regional vascular tone
2. Compliance of central compartment
· Vascular tone
· Right ventricular compliance:
§ Myocardial disease
§ Pericardial disease
§ Tamponade
3. Tricuspid valve disease
· Stenosis
· Regurgitation
4. Cardiac rhythm
· Junctional rhythm
· Atrial fibrillation
· Atrio-ventricular dissociation
5. Reference level of transducer
· Positioning of patient; the patient is not always in flat supine position.
6. Intrathoracic pressure
· Respiration
· Intermittent positive pressure ventilation
· Positive end-expiratory pressure
· Tension pneumothorax
Alternatives to CVP measurement in assessing the volume status:
Commercially available equipment for assessing dynamic preload variables:
· Stroke volume variation (SVV) using transesophageal Doppler (TED).
· Minimally invasive cardiac output monitoring devices:
§ Pulse wave analysis
§ Lithium dilution CO
§ Electrical bioimpedance
§ Partial CO2 rebreathing
§ Pulsed dye densitometry
What is the evidence provided by this article?
This is a narrative review article
Level of evidence grade 5.
Club 8; CVP use in KT
Summary
· CVP was used for decades as an indicator of the volume status, need for fluid resuscitation and response to fluid resuscitation therapy.
· However, many studies concluded that it is not reliable tool to assess the volume status. Instead, combination of many clinical and none invasive tools can be utilized to assess the volume status.
· CVP is not the ideal assessment tool in kidney transplant recipients as it is affected by many factors as ventricular compliance, vascular tone, presence of any arrhythmia, any valvular lesion, pericardial or myocardial disease, position of the patient and transducer, intrathoracic pressure which is affected by mechanical ventilation.
· Assessment of volume status in transplant patient is crucial as hypovolemia impairs the graft perfusion and over-hydration leads to pulmonary edema and prolonged hospitalization.
· Causes of inappropriateness of CVP Intraoperative:
o table tilt affects the readings as the patient not lie flat.
o Pressure of retractors affects the intra-abdominal pressure,
o Swing in vascular tone in those patients with use of vasodilator anti-hypertensives as ccb, alpha and beta blockers.
o Use of CVC itself carries a risk of central vein stenosis and precludes ipsilateral AVF creation.
· New available tools for assessment of volume status:
o Intraoperative trans-esophageal Doppler to measure SVV (stroke volume variability), had similar outcome as regard graft function with less risk of fluid overload than CVP guided fluid therapy, with less ICU stay and rapid recovery.
o In conclusion, new available methods as pulse wave analysis and lithium dilution technology have their own limitations and should be used on individual bases.
Level of evidence: level V (narrative review)
This review article was published in chest journal an impact factor of10.26 .
SUMMARY
This article reviews the data from previous research between 1966=2007 addressing the value of CVP to guide IVF management in critically ill patients, by a systematic review of all studies from midline PubMed, Cochrane
CVP central venous is referred to the pressure measured in the right atrium or SVC and its thoughts its correlated to intravascular volume and can help in estimating the intravascular fluid and blood depletion it’s used for assessment of fluid management in critically ill patients in ICU, ER and intraoperative however the evidence of such practice been tested by a systematic review of previous studies which support such practice.
According to this systematic review of 24 studies that fit the inclusion criteria all failed to show any correlation between the CVP and the volume status, none of these studies took into consideration the positive end-expiratory pressure levels or changes in intrathoracic pressure account when measuring the CVP, the rt ventricular filling does not depend on CVP only we need the transmural rt atrial pressure gradient which in reality barely calculated
By principle, the only reason to challenge patients with volume is to increase the stroke volume, and once the starling law reached the even level (plateau) at this stage continuing the given volume will do harm and lead to interstitial edema with tissue hypoxemia so it’s important during resuscitation to assess the patient for fluid responsiveness or not.
CVP measurement can mislead the calculation of the IVF replacement and increase the risk of volume overload and pulmonary edema in sepsis, ICU critical patients, and intraoperative which is associated with higher mortality, the fact that CVP is not ideal to reflect the vascular volume status and can be misleading tool have been studied a long time ago by many observational studies back to 1970s, however, after this systematic review the CVP should not be used for ICU, intraoperative and in an emergency as a tool to guide IVF replacement and should be still used in selection post-cardiac surgery and PE in order to assess the RT ventricular filling, not the volume status.
alternative suggestion includes intra and post-operative cardiac output monitoring devices and not CVP monitoring in kidney transplant candidates .
Strength of this review
1. Demanding selection criteria used to identify relevant studies
2. the use of quantitative endpoints
3. The studies are outstanding for the consistency
(Both in magnitude and direction) of their findings which point to the true findings
Level of evidence 5, a narrative systematic review of observational studies no RCT
Summary of the article;
In the CPV was used for halve century , as guide for fluid status in renal transplantation.
In present with advances in tools measuring and assessing fluid status, CVP was obsolete and prooved that neither it indicate cardiac stroke volume, nor intravascular volume.
Marik et al,;
Found that CVP is not realiable indicator for fluid ststus.
Cecconi et al,;
CVP can not be reabily used as guide fluid status.
A survey study in Canadian physician found that 89% of them use CVP as guidance in septic shock.
Bignami et al.;
Questionare dine in 77 centers in Italy found that CVP used frequently as fluid guidance, by 26% followed by Arterial blood pressure 19% and Echo 5.6%.
Sendergaard et al.;
CVP was not though guide Preload, use to assess fluid load, cardiac performance and vascular resistance.
During transplant operation, recipient exposed to many intraoperative factors that alter the CVP reading, thesefactors are;
Possible alternative for fluid measurement;
Conclusion;
Level of evidence ((V))
only a few studies have reliably to assess the role of CVP in comparison to other modern techniques in the field of renal transplantation.
This study aims to answer this question in regards to clinical application of CVP
the study validated the role of CVP in certain situations as severe congestive heart failure or hypovolemia, where the use of CVP is valuable in guiding fluid managemen
LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION
These factors can be summarized in the following points:
(1) During the operation, the position of the patient is not always inflat supine position.
The effect of posture changes on CVP reading was documented since a long time
(2) transplant surgery always entails the use of abdominal retractors. These retractors must have a pressure effect on the viscera and subsequently affect the venous return
(3) (PPV) during the transplant operation will affect the CVP reading
(4) The target intraoperative CVP remains elusive.
aggressive hydration ensures good allograft pe rfusion. On the other hand, overhydration carries the risk of pulmonary congestion, pulmonary oedema
(5) the effect of ageing, longstanding hypertension and the use of various medications affecting the peripheral vascular resistance
(6) place ment of central venous catheters and other devices may result in central vein stenosis.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
The introduction of stroke volume variation (SVV)] considered a revolutionary advance in perioperative fluid management.
Several other noninvasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM
each one of these novel, noninvasive techniques has its own limitations
Lithium dilution
LiDCOplus™
advantages
Disadvantages
Pulse wave analysis
LiDCOrapid™ and FloTrac/Vigileo™
Advantages
Disadvantages
Level 5
This level of evidence doesn’t have the power of evidence to change of practice we need more and more studies
Summary:
Adequate intravenous fluid therapy is essential in renal transplant recipients to ensure a good allograft perfusion. Central venous pressure (CVP) has been considered the cornerstone to guide the fluid therapy for decades; it was the only available simple tool worldwide. However, the revolutionary advances in assessing the dynamic preload variables together with the availability of new equipment to precisely measure the effect of intravenous fluids on the cardiac output had created a question mark on the future role of CVP.
The introduction of commercially available equipment for assessing dynamic preload variables [e.g., stroke volume variation (SVV)] considered a revolutionary advance in peri-operative fluid management. The use of intraoperative transesophageal Doppler (TED) to estimate the corrected flow time and variation in stroke volume values.
TED was used to guide intraoperative fluid management in 110 living donor renal transplant recipients, and the outcome was compared with the historical records of 104 control recipients who received CVP guided fluid management over the previous year. They concluded that TED was associated with a similar rate of immediate graft function. Moreover, it was associated with a significantly less amount of intra-operative intravenous (IV) fluids, and reduced incidence of postoperative fluid overload.
Furthermore, several other non-invasive techniques are utilised for cardiac output assessment and IV fluid guidance like lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM).
Although CVP measurement continues to be popular, yet it is not ideal for guiding and monitoring of fluid management in renal transplantation.
Level of evidence 5
CVP has been used to guide fluid therapy in therapy in kidney transplantation. Several studies showed that CVP correlates poorly with cardiac output or intravascular volume. The utility of CVP measurement in KT
needs further evaluation.
It is not the best tool for assessing and guiding fluid therapy in renal transplantation as It is affected by several physical and anatomical factors.
Drawbacks and limitations of CVP in relation to renal transplantation:
– The effect of posture changes on CVP reading, as the patient is not always in a flat supine position.
– The use of abdominal retractors affects intrabdominal and intrathoracic pressure, affecting venous return.
– PPV during the transplant operation will affect the CVP reading.
– The target of intra-operative CVP is not yet identified.
– Fluctuation of CKD patients’ fluid status make the CVP target difficult.
– The effect of ageing, long-standing hypertension, and medications would be confounding.
– Consider the risk of central vein stenosis when using a central device.
A possible alternative for fluid status monitoring:
–Intraoperative transesophageal Doppler (TED).
-lithium dilution technology.
-Arterial pulse wave analysis
– Electrical bio-impedance Partial CO2 rebreathing.
– Pulsed dye densitometry
Several trials investigated the reliability of these new techniques to guide fluid therapy in surgical cases.
Conclusion:
Due to several limitations, CVP is not ideal for guiding and monitoring fluid management in renal transplantation. Using output monitoring devices combined with other hemodynamic variables for patient evaluation and management is recommended in KT
Level of evidence: 5 narrative review.
Thank you.
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based?
1. Summarise this article
History
CVP for assessment of intravascular fluid volume is in use for >50 years; it measures pressure in the SVC or RA, & thus reflects RV preload.
Marik et al: said CVP is not a reliable indicator of fluid status & should not be used to guide fluid management.
Marik et al (meta-analysis): abandoned use of CVP as a guide in fluid management.
Cecconi et al: CVP or end diastolic volume can’t reliably guide fluid resuscitation; >1 hemodynamic variable recommended.
Current practice
Canada:
89.2% of physicians use CVP monitoring in septic shock.
78.7% of clinicians consider CVP defined endpoints as the end-point of volume resuscitation in early septic shock.
Italy (Bignami et al): after cardiac surgery, CVP used most frequently (26.7%); arterial BP (19.7%) & echo-cardiography (5.6%).
Sondergaard et al: CVP used to assess volume status, heart performance & systemic vascular resistance.
CVP in KTX
CVP reading is affected by:
1.Position of the patient (not always flat supine during surgery).
2.Abdominal retractors have a pressure effect on the viscera & thus affect the venous return.
3.The PPV during the TX operation will affect the CVP.
4.Ageing
5.Long-standing HTN
6.Medications affecting the peripheral vascular resistance (α-blockers, β-blockers & CCBs)
7.Fluctuation between the volume overload state
& the dry state during the post-dialysis period.
Commercial tools for assessing fluid management:
1.Intra-op TED (Srivastava et al, 110 LKD KTRs): outcome comparable to the historical records of 104 control recipients who received CVP guided fluid management over the previous year.
2.Kumar et al: use of SVV (obtained from minimally invasive cardiac output monitor): the new technique was associated with:
– lower amount of IV fluids
– shorter ICU stay
– shorter hospital stay (non-significant)
3.Lithium dilution technology (e.g., LiDCO plusTM machine) & arterial pulse wave analysis (e.g., FloTrac /Vigileo TM):
Each has its own limitations.
Conclusion
CVP measurement is not ideal for guiding fluid management in KTRs.
The large variations in intravascular volume status will render reliance on CVP imprecise; pulmonary edema could be the 1stsign of fluid overload.
The patient position, the use of retractors, & the PPV make any CVP reading meaningless.
The authors suggest that CVP measurement be abandoned in KTX because it may be misleading.
The authors recommend, as an alternative to CVP, using intra-op & post-op cardiac output monitoring devices for guiding fluid therapy in KTRs.
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2.What is the evidence provided by this article?
Level V
Thank you.
-Introduction
Multiple studies concluded that CVP does not correlate with intravascular volume nor valid as a guide for fluid therapy.
Fluid resuscitation is crucial in critically ill patients, which directly affect the outcome.
CVP historical use
Marik et al stated that CVP is not an indicator of fluid status and must be abandoned as a guide for fluid management.
Cecconi et al adviced using multiple hemodynamic variables together for better evaluation of the volume status and highlighted the CVP utility in certain cases for fluid therapy guidance as in CHF and hypovolemia.
CVP in current practice
CVP remains the base of clinical practice as noted in a survey done in Canada and still in use as declared by other studies .
Limitations of CVP in renal transplantation
CVP is affected by multiple factors as central venous blood volume , compliance of central compartment as positive pressure ventilation (PPV) during the
transplant operation can affect the CVP ,heart rhythms , tricuspid valve diseases, the reference transducer level as CVP is variable with different positioning and retractors used intraoperative can affect the venous return and can affect the intrathoracic pressure as well as ageing , long standing hypertension and the use of drugs affecting peripheral vascular resistance therefore CVP can mislead decision making of fluid therapy in renal transplantation.
Targeted intraoperative CVP is unknown , in the postdialysis period the CVP is fluctuating for the patients so it is difficult to know the normal CVP reading.
Central venous stenosis is a complication of central venous catheter introduction which can negatively affect AV fistula or graft needed to be done on the same limb if the patient needed dialysis in a later stage.
Alternatives for fluid staus monitoring
Srivastava et al published that TED correlated with immediate graft function, TED use was associated with a significantly less amount of intra-operative IV fluids, and less incidence of postoperative fluid overload.
Kumar et al stated that stroke volume velocity decreased the amount of IV perioperative fluid used as well as ICU stay.
Lithium dilution technology and arterial pulse wave analysis are noninvasive methods used for assessment of cardiac output and guide IV fluid therapy.
Each one of those methods have it’s limitations and advantages.
For example pulse wave analysis advantage are only requiring arterial line,CO monitoring beat by beat ,but drawbacks is that arrhythmia can reduce it’s accuracy.
Lithium dilution is a simple method but is affected by neuromuscular blocking drugs.
Pulse dye densitometry is non invasive but it’s assessment is intermittent and hemodynamic instability affects it’s accuracy.
Conclusion
CVP continues to be the most popular method used although it was proved that it is not reliable for fluid assessment nor for guidance of fluid therapy.
CVP is affected by multiple factors rendering it an unreliable method to monitor or navigate fluid management in renal transplantation.
Intra-operative and post-operative cardiac output monitoring devices are adviced for guiding fluid therapy in renal transplant recipients instead of CVP.
For ward monitoring regular vital signs monitoring is recommended as daily body weight.
-Level of evidence is V
I liked reading your summary and analysis.
Ajay
VIII. Utility of central venous pressure measurement in renal transplantation – Is it evidence based?
——————————————————————————————————————-
Drawbacks and limitations to the use of CVP in kidney transplantation
Alternative tools to CVP in monitoring of fluid status
Conclusion
What is the evidence provided by this article?
The level of evidence is V
I liked reading your summary and analysis.
Ajay
Thanks alot Prof.Sharma
SUMMARY
Introduction
The assessment of intravascular fluid status either in the ICU or during surgeries has rested solely on the use of central venous pressure for over half of the century, but the narrative is gradually changing due to more recent ways of measurement of CVP and also the outcome of some studies against its reliability. However, some studies validated the use of CVP for fluid management in some situation, but it uses in kidney transplantation has not been helpful and this is part of what this article is set out to answer.
Drawbacks and limitations to the use of CVP in kidney transplantation
Alternative tools to CVP in monitoring of fluid status
Conclusion
CVP still has a growing popularity, but this is not enough to certify it as a reliable tool to measure fluid status particularly during kidney transplantation surgery as it has been shown to be with a lot of drawbacks and limitations which can also affect the successful outcome of the procedure.
The level of evidence is 5
Thank you
Introduction
Central venous pressure (CVP) measurements have been used to assess intravascular fluid status of patients, especially renal transplant recipients. Some studies have shown that CVP measurements do not correlate with cardiac output and the intravascular volume status. The study is aimed to objectively assess the validity of using CVP measurements in renal transplant patients.
In theory, CVP measurements involve the measure of the pressure in the superior vena cava (SVC) or the pressure in the right atrium – these reflect the right ventricle preload.
Marik et al published a systematic review which evaluated the relationship between CVP and the fluid status of the patient. The study concluded CVP is an unreliable indicator of the fluid status and hence it would be unwise to use it as a guide to fluid management.
Cecconi et al published a study that concluded that using CVP or end diastolic volume in isolation is not a reliable guide to fluid resuscitation. However, CVP can be used for certain conditions, for example in severe congestive heart failure or hypovolemia.
Data collected from Italy and Canada indicated that clinicians prefer to use CVP measurements for monitoring intravascular fluid status, followed by arterial BP and echocardiography.
Drawbacks and limitations of CVP in relation to renal transplantation:
Availability of modern medical advances have altered the approach of assessing intravascular fluid status.
CVP readings are affected by several factors, such as:
Central venous blood volume
Compliance of central compartment
Tricuspid valve disease
Cardiac rhythm
Reference level of transducer
Intrathoracic pressure
Intraoperatively, CVP measurements can also be altered:
CKD patients on dialysis have fluctuating fluid status, hence it is difficult to determine the ideal CVP for them
There is also the increased risk of central vein stenosis.
Possible alternatives for fluid status monitoring
Pulse wave analysis
Lithium dilution
Electrical bio-impedance
Partial CO2 rebreathing
Pulsed dye densitometry
ConclusionCVP is shown to be the popular option amongst clinicians. However, the readings may be misleading, as many factors affect the measurement. Understanding the limitations of the cardiac output monitoring devices will help us better utilize them for more robust monitoring of fluid status in renal transplant patients. It is recommended not to use the CVP to guide fluid management in renal transplant patients
Level of evidence is Level V
Thank you
CVP measurement is commonly used to assess fluid status and guide fluid therapy in kidney transplant recipients.
It is used to determine resuscitation goals, however several studies showed no correlation between CVP measurement and intravascular volume.
Historical use of CVP:
It was used to correlate with intravascular fluid volume and volume status of the patients as it measure pressure in right atrium that reflect the right ventricle preload.
A systemic review and meta analysis showed CVP was indicating fluid status and shouldn’t guide fluid management.
CVP also was not reliable when used alone.
CVP in the current practice:
It is very popular in clinical practice, in resuscitation practices, it is used for monitoring in septic shock and determine the endpoint of fluid resuscitation.
After cardiac surgery, It is the most commonly used method for hemodynamic monitoring.
Drawbacks and limitations of CVP in relation to renal transplantation:
The measurement is affected by several physiological and anatomical factors including:
Possible alternatives for fluid status monitoring:
Intraoperative transesophageal doppler: guide fluid management and was associated with similar rate of intraoperative IV fluids with reduced post operative fluid overload.
Minimally invasive cardiac output measurement assessing stroke volume variation was associated with lower amount of IV fluids and significantly shorter ICU stay
Noninvasive tools are used as part of enhanced recovery programs.
Lithium dilution technology and arterial pulse wave analysis are recent and non invasive but with several limitations.
Clinician should choose the modality according to each clinical scenario individually
Conclusion:
It is suggested that CVP shouldn’t be used in kidney transplant recipients as it may be misleading.
Cardiac output monitoring devices are recommended to be used intra and post operative, while in ward, regular monitoring of vital signs and daily body weight can be used.
Level of evidence: 5 (Review article)
Thank you
Summarise this article
INTRODUCTION
Optimum fluid resuscitation is essential to maximise the outcomes in critically ill patients
Although CVP have been used for a long time, it is correlated to cardiac output and intravascular volume status
CVP
Historical use
Marik et al studied the relationship between CVP and the fluid status of the patients and concluded that CVP is an unreliable indicator of the fluid status and should not be used as a guide to fluid management
Cecconi et al recommended that CVP should not be used alone for evaluation and management unless in severe CHF or hypovolemia
CVP in the current practice
CVP still used in most clinical practice. For example, in Canada 89.2% of physicians use CVP in septic shock
Limitations in renal transplantation
CVP is not the ideal tool of measurement of fluid balance. It is affected by several factors:
1. Central venous blood volume
2. Compliance of central compartment
3. Tricuspid valve disease
4. Cardiac rhythm
5. Reference level of transducer (postion of the patient)
6. Intrathoracic pressure
Intraoperative factors that change the CVP reading:
1. The position of the patient is not always in flat supine position
2. Use of abdominal retractors (reduce venous return by pressing the viscera)
3. Positive pressure ventilation (PPV )
4. No intraoperative exact target of CVP
5. Determination of the normal CVP is difficult in dialysis patient
6. Central vein stenosis
7. Ageing, longstanding HTN and the use of medications affecting the peripheral vascular resistance (alpha blockers, beta blockers and calcium channel blockers)
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING
1. Intraoperative transesophageal Doppler (TED). When compared with CVP, TED was associated with a similar rate of immediate graft function and significant less amount of intraoperative intravenous fluids, and reduced incidence of postoperative fluid overload
2. Stroke volume variation (SVV)
3. lithium dilution technology (e.g., LiDCOplusTM machine) and arterial pulse wave analysis (e.g., FloTrac/VigileoTM)
CONCLUSION
CVP is not ideal for guiding fluid therapy in renal transplantation
Intraoperative factors like position and refractors affect the CVP
Other alternative devices should be used in renal transplantation for guiding fluid therapy (intraoperative and postoperative cardiac output monitoring devices)
What is the evidence provided by this article?
Level 5 (narrative review)
Thank you
INTRODUCTION:
Since the 1960s, central venous pressure (CVP) has been used to monitor intravascular fluid status in renal transplant patients and guide intravenous fluid management. With diagnostic tool advancements, CVP’s utility is debatable. Several investigations showed that CVP measures are not connected to cardiac output nor intravascular volume status, hence its utility in fluid management of renal transplant recipients remains questionable.
Current CVP measurement :
CVP assessment is important in clinical practice. 89.2% of Canadian doctors utilize CVP to monitor septic shock. 78.7% of Canadian doctors considered CVP endpoints the end-point of volume resuscitation in early septic shock.
LIMITATIONS OF CVP IN RELATION TO RENAL TRANSPLANTATION:
–During kidney transplant surgery, intraoperative variables may change CVP.
-Patient isn’t always supine throughout the surgery.
-Transplants need abdominal retractors. These retractors will alter visceral pressure and venous return.
-Positive pressure ventilation (PPV) affects CVP during transplant surgery.
-the target intra-operative CVP remains elusive.
-CKD patients on dialysis oscillate between volume overload and dry state post-dialysis, making it difficult to determine a normal CVP measurement.
POSSIBLE ALTERNATIVES FOR FLUID STATUS MONITORING:
–Pulse wave analysis:limitation: The presence of an arterial line with optimum waveform signal is a prerequisite.
-Intraoperative trans-esophageal Doppler (TED): to measure flow time and stroke volume (SVV). It reduced intra-op IV fluids and post-op fluid overload.
-Lithium dilution: Some neuromuscular blocking medicines impact accuracy; lithium chloride is contraindicated for lithium salt patients.
-CONCLUSION
CVP measurement remains popular, although it’s not suitable for renal transplant fluid management.
We advocate intra- and post-operative cardiac output monitoring devices to guide fluid treatment in renal transplant patients. Knowing their limits improves fluid treatment monitoring.
Level of evidence V
Thank you
CVP measures the pressure in the SVC or the right atrium pressure, which reflects the right ventricle preload. It is assumed to provide a reliable information about the patients circulatory and volume status. Studies showed that CVP is an unreliable indicator of the fluid status and some authors suggested abandoning the use of CVP as a guide in fluid management, while others reported that it can be used to assess volume status, heart performance, and systemic vascular resistance.
Factors affecting the CVP reading during kidney transplant operation:
· Position of the patient as the operating table may be tilted during surgery,
· Pressure and tension of abdominal retractors,
· Positive pressure ventilation,
· Difficulty in determining the normal CVP of a CKD patient on dialysis,
· The risk of damage to central veins during catheterization, which may affect future dialysis access.
Alternatives to CVP measurement in renal transplant:
· Intraoperative trans-esophageal Doppler (TED): to estimate the corrected flow time and variation in stroke volume values(SVV). it was associated with a decreased amount of intra-op IV fluids, decreased incidence of postop fluid overload.
· SVV: from minimally invasive cardiac output monitor, to guide the peri-op IVF fluid replacement in major abdominal surgery. It helps lower the amount of IVF, offers shorter ICU stay, and a non-significant shorter hospital stay.
· Lithium dilution technology: e.g., LiDCOplusTM machine, and
· Arterial pulse wave analysis.
This is a level 5 evidence, review article
Thank you
This is a review (level of evidence V) evaluating the rule of CVP in assessment of fluid status in renal transplantation in comparison to the recent dynamic monitoring strategies and they suggest the following:
A- CVP should not be used for assessment of fluid status in renal transplantation due to the following :
B- Fluid therapy can be guided using cardiac output monitoring devices
Thank you
Summary : Utility of central venous pressure measurement in renal transplantation – is it evidence based?
This study is about CVP measurement in renal transplant and its efficacy and place in improving transplant outcome for the graft and patient.
CVP has been used to guide fluid therapy in transplant patients. However, the authors of this study recommend avoiding CVP measurement as it can mislead the transplant team in terms of fluid resuscitation. In particular, even changes in patient position influence CVP reading, making it highly unreliable as a single marker for action.
Alternatively, intraoperative and postoperative cardiac output monitoring devices are recommended to be used. Regular monitoring of vital signs along with daily body weight measurement has been seen to be useful in recognizing harmful changes in the patient, allowing space for immediate action and early treatment. This can bring about a better outcome than manipulation of fluids based on CVP readings alone.
These devices that can be used as alternatives to CVP for fluid status monitoring include intraoperative TED or transedophageal doppler, SVV, lithium dilution technology and arterial pulse waves analysis. Each of these techniques has limitations but their advantages warrant their use.
Level of evidence
This article is a narrative review, hence level of evidence is 5.
Thank you,
Will you change your practice based on this article?
Definitely, considering the fluctuation of CVP because it is influenced by multiple factors. Like the article mentions, a combination of different factors need to be considered in guiding fluid management appropriately in critically ill patients so that we do not ignore possible dehydration and at the same time avoid fluid overload and the host of complications that come along with it such as pulmonary edema.
Alternatives to CVP for intravascular volume assessment:
Advantages & limitations of these non invasive methods should be considered in chosen the best method.
level of evidence is 5.
Thank you,
Will you change your practice based on this article?
Yes I will
This was a narrative review, level 5
Hi Dr Ban,
I liked reading your summary and analysis, Will you change your practice based on this article?
Ajay
Yes, prof
thank you