Kidney transplantation: recent developments and recommendations for anesthetic management

Considerations regarding anesthesia for renal transplantation

Renal transplantation is a complex surgical procedure requiring meticulous anesthetic planning to ensure patient safety and optimal graft function. In this comprehensive review, we examined various aspects of anesthesia management during renal transplantation, including preoperative, intraoperative, and postoperative care. Preoperative optimization involves the identification and management of risks to mitigate perioperative complications. Treatment with erythropoiesis-stimulating agents is recommended to correct anemia in transplant recipients with hemoglobin levels below 9-10 g/dl. Intraoperative management focuses on hemodynamic monitoring, maintenance of intravascular volume, and careful selection of anesthetic techniques. Neuromuscular monitoring and the appropriate use of neuromuscular blocking and reversal agents are considered essential. Further, hemodynamic goals include maintaining the mean arterial pressure within the range of 80-110 mmHg. In addition, attention should be paid to perioperative glycemic control, temperature management, and diuretic use. In postoperative management, multimodal analgesia and the prevention of postoperative delirium contribute to optimal recovery. The implementation of enhanced recovery after surgery principles can further improve outcomes. Collaborative efforts among surgical teams, anesthesiologists, and healthcare professionals are crucial for achieving successful renal transplantation outcomes.

Robot-assisted kidney transplantation: an update

Renal transplantation has become the gold-standard treatment for the majority of patients with established renal failure. Recent decades have seen significant progress in immunosuppressive therapies and advances in post-transplant management of recipients, resulting in improved graft and patient outcomes. However, the open technique of allograft implantation has stood the test of time, remaining largely unchanged. In a world where major advances in surgery have been facilitated by innovations in the fields of biotechnology and medical instrumentation, minimally invasive options have been introduced for the recipient undergoing kidney transplantation. In this review we present the evolution of minimally invasive kidney transplantation, with a specific focus on robot-assisted kidney transplant and the benefits it offers to specific patient groups. We also discuss the ethical concerns that must be addressed by transplant teams considering developing or referring to robotic programs.

The effect of pulse pressure variation compared with central venous pressure on intraoperative fluid management during kidney transplant surgery: a randomized controlled trial

BACKGROUND

Traditionally, fluid administration during kidney transplant surgery is guided by central venous pressure (CVP) despite its limited reliability as a parameter for assessing intravascular fluid volume, particularly in patients with cardiovascular diseases. The recommended goals at graft reperfusion are a mean arterial pressure of 90 mm Hg and a CVP of 12-14 mm Hg. This approach may increase the risk of significant adverse effects due to volume overload. Perioperative fluid therapy guided by dynamic indices of fluid responsiveness has been shown to optimize intravascular volume and prevent complications associated with overzealous administration of fluids in major abdominal surgeries. We hypothesized that pulse pressure variation (PPV)-guided fluid administration would result in better optimization of intravascular fluid volume compared with a CVP-guided strategy during kidney transplant surgery.

METHODS

In this single-centre randomized double blinded trial, 77 end-stage renal disease patients, who underwent kidney transplant surgery under general anesthesia with epidural analgesia, were randomized to receive either CVP-guided (n = 35) or PPV-guided (n = 35) fluid therapy using predefined hemodynamic endpoints. The primary outcome was the total volume of intraoperative fluids administered. Secondary outcomes were intraoperative hemodynamic changes, serum lactate levels, serum creatinine, need for dialysis within the first week, creatinine elimination ratio, and incidence of immediate and delayed graft dysfunction.

RESULTS

Results were analyzed for 70 patients. Eighty percent of the patients underwent living-related donor allograft kidney transplant. Operative variables related to donor characteristics, duration of surgery, graft cold ischemia time, and blood loss were comparable in both groups. The mean (standard deviation) volume of intravenous fluids administered intraoperatively was 1,346 (337) mL in the PPV-guided group vs 1,901 (379) mL in the CVP-guided group (difference in means, 556 mL; 95% confidence interval, 385 to 727; P = 0.001). There were no significant differences in secondary outcomes between the two groups.

CONCLUSION

Pulse pressure variation -guided fluid administration significantly decreased the total volume of crystalloids compared with CVP-guided fluid therapy during the intraoperative period in patients who underwent kidney transplant surgery. Nevertheless, our study was underpowered to detect differences in secondary outcomes.

TRIAL REGISTRATION

www.ctri.nic.in (CTRI/2018/01/011638); registered 31 January 2018.

Blood Pressure Management After Reperfusion in Living-Donor Kidney Transplantation

BACKGROUND

The central focus of anesthesia management in kidney transplantation is to avoid hypotensive episodes and maintain adequate perfusion pressure to the graft. However, it is not clear whether there is an optimal systolic blood pressure (SBP) level after reperfusion for living-donor transplant outcomes. The aim of this study is to investigate the effect of SBP after reperfusion on early graft function in living-donor kidney transplantation.

METHODS

We retrospectively analyzed 315 patients who underwent living-donor kidney transplantation from January 2013 to December 2017. We divided the patients into 4 groups according to SBP after reperfusion and compared the postoperative estimated glomerular filtration rate and creatinine.

RESULTS

There were no differences in the postoperative recovery of kidney graft function in the first 7 postoperative days among the 4 SBP groups after reperfusion. However, the urine output after reperfusion was significantly less in the group with SBP < 140 mm Hg after reperfusion compared with the remaining 3 groups in a multivariate analysis (P = .04).

CONCLUSIONS

No significant differences in early graft function were observed among the 4 SBP groups. SBP ≥ 140 mm Hg after reperfusion, which is linked to greater urine output, can be beneficial in terms of long-term graft survival and mortality.

[Pulse pressure variation guided fluid therapy during kidney transplantation: a randomized controlled trial]

PURPOSE

Kidney transplantation is the gold-standard treatment for end stage renal disease. Although different hemodynamic variables, like central venous pressure and mean arterial pressure, have been used to guide volume replacement during surgery, the best strategy still ought to be determined. Respiratory arterial Pulse Pressure Variation (PPV) is recognized to be a good predictor of fluid responsiveness for perioperative hemodynamic optimization in operating room settings. The aim of this study was to investigate whether a PPV-guided fluid management strategy is better than a liberal fluid strategy during kidney transplantation surgeries. Identification of differences in urine output in the first postoperative hour was the main objective of this study.

METHODS

We conducted a prospective, single blind, randomized controlled trial. We enrolled 40 patients who underwent kidney transplantation from deceased donors. Patients randomized in the PPV Group received fluids whenever PPV was higher than 12%, patients in the Free Fluid Group received fluids following our institutional standard care protocol for kidney transplantations (10mL.kg^-1.h^-1).

RESULTS

Urinary output was similar at every time-point between the two groups, urea was statistically different from the third postoperative day with a peak at the fourth postoperative day and creatinine showed a similar trend, being statistically different from the second postoperative day. Urea, creatinine and urine output were not different at the hospital discharge.

CONCLUSION

PPV-guided fluid therapy during kidney transplantation significantly improves urea and creatinine levels in the first week after kidney transplantation surgery.

Pulse pressure variation guided fluid therapy during kidney transplantation: a randomized controlled trial

Purpose

Kidney transplantation is the gold-standard treatment for end stage renal disease. Although different hemodynamic variables, like central venous pressure and mean arterial pressure, have been used to guide volume replacement during surgery, the best strategy still ought to be determined. Respiratory arterial Pulse Pressure Variation (PPV) is recognized to be a good predictor of fluid responsiveness for perioperative hemodynamic optimization in operating room settings. The aim of this study was to investigate whether a PPV guided fluid management strategy is better than a liberal fluid strategy during kidney transplantation surgeries. Identification of differences in urine output in the first postoperative hour was the main objective of this study.

Methods

We conducted a prospective, single blind, randomized controlled trial. We enrolled 40 patients who underwent kidney transplantation from deceased donors. Patients randomized in the “PPV” group received fluids whenever PPV was higher than 12%, patients in the “free fluid” group received fluids following our institutional standard care protocol for kidney transplantations (10 mL.kg^-1. h^-1).

Results

Urinary output was similar at every time-point between the two groups, urea was statistically different from the third postoperative day with a peak at the fourth postoperative day and creatinine showed a similar trend, being statistically different from the second postoperative day. Urea, creatinine and urine output were not different at the hospital discharge.

Conclusion

PPV guided fluid therapy during kidney transplantation significantly improves urea and creatinine levels in the first week after kidney transplantation surgery.

Perioperative fluid management in kidney transplantation: a black box

The incidence of delayed graft function in patients undergoing kidney transplantation remains significant. Optimal fluid therapy has been shown to decrease delayed graft function after renal transplantation. Traditionally, the perioperative volume infusion regimen in this patient population has been guided by central venous pressure as an estimation of the patient’s volume status and mean arterial pressure, but this is based on sparse evidence from mostly retrospective observational studies. Excessive volume infusion to the point of no further fluid responsiveness can damage the endothelial glycocalyx and is no longer considered to be the best approach. However, achievement of adequate flow to maintain sufficient tissue perfusion without maximization of cardiac filling remains a challenge. Novel minimally invasive technologies seem to reliably assess volume responsiveness, heart function and perfusion adequacy. Prospective comparative clinical studies are required to better understand the use of dynamic analyses of flow parameters for adequate fluid management in kidney transplant recipients. We review perioperative fluid assessment techniques and discuss conventional and novel monitoring strategies in the kidney transplant recipient.

The New Kidney Donor Allocation System and Implications for Anesthesiologists

Given potential disparity and limited allocation of deceased donor kidneys for transplantation, a new federal kidney allocation system was implemented in 2014. Donor organ function and estimated recipient survival in this system has implications for perioperative management of kidney transplant recipients. Early analysis suggests that many of the anticipated goals are being attained. For anesthesiologists, implications of increased dialysis duration and burdens of end-stage renal disease include increased cardiopulmonary disease, challenging fluid, hemodynamic management, and central vein access. With no recent evidence to guide anesthesia care within this new system, we describe the kidney allocation system, summarize initial data, and briefly review organ systems of interest to anesthesiologists. As additional invasive and echocardiographic monitoring may be indicated, one consideration may be development of a dedicated anesthesiology team experienced in management and monitoring of complex patients, in a similar manner as has been done for liver transplant recipients.

Intraoperative hemodynamic factors predicting early postoperative renal function in pediatric kidney transplantation

BACKGROUND

The anesthetic management of kidney transplantation in children remains somewhat empirical. The goal of the present study was to investigate intraoperative hemodynamic factors affecting posttransplantation kidney function.

METHODS

We performed a retrospective analysis of data from patients undergoing kidney transplantation in our pediatric teaching hospital from 2000 to 2014. Data collected included: donor and recipient demographic data, recipient comorbidities, fluids administered intraoperatively, and intraoperative blood pressure and central venous pressure. The main outcome of the study was the creatinine clearance at day 1 corrected to a body surface area of 1.73 m². Analysis was performed using Classification Tree Analysis with 10-fold cross-validation.

RESULTS

One hundred and two patients were included. The following predictors of increased postoperative creatinine clearance at day 1 were identified: decreasing recipient weight, mean blood pressure-to-weight ratio 10 minutes after reperfusion, reduced cold ischemia duration, and increased intraoperative albumin infusion. Increased creatinine clearance was observed when mean blood pressure-to-weight ratio 10 minutes after reperfusion was ≥4.3 in patients weighing 13-21 kg and ≥2.5 in those ≥22 kg. Overall, the model explained 64% (and at cross-validation 60%) of creatinine clearance variability at day 1.

CONCLUSION

Intraoperative hemodynamics during kidney transplantation should be optimized in order to increase mean blood pressure according to values indicated by our analyses. Cold ischemia duration should be shortened as far as possible.

Risk factors and outcomes associated with a higher use of inotropes in kidney transplant recipients

Preservation of adequate perfusion pressures to the graft is a main focus of intraoperative management during kidney transplantation. We undertook this study to investigate the incidence of the higher use of inotropes in kidney transplant recipients and identify the patient outcomes and preoperative and intraoperative variables related to this.We retrospectively analyzed 1053 patients who underwent kidney transplantation at Asan Medical Center between January 2006 and February 2012, stratified by their inotropic score ([dopamine] + [dobutamine] + [epinephrine × 100] + [norepinephrine × 100]) <7 versus ≥7, wherein all doses are expressed as μg/kg/min. We evaluated preoperative characteristics, hemodynamic parameters, and intraoperative variables as well as postoperative outcomes, such as length of hospital stay and 1-year rejection and mortality rate.Receiver-operating characteristic analysis was performed to determine inotropic score to predict 1-year mortality. An inotropic score of 7 had the best combined sensitivity and specificity. An inotropic score ≥7 (137 patients, 13.0%) was significantly more prevalent in older patients, those with polycystic kidney disease, and at a 2nd transplant. Anesthesia time, the amounts of crystalloid and 5% albumin infused, and the need for red blood cell transfusion were significantly higher in the inotropic score ≥7 group. The patients with a higher use of inotropes required longer postoperative hospital stay and experienced a >2-fold higher rejection within the 1st year and a 4-fold higher 1-year mortality rate.A higher use of inotropes in kidney transplant recipients is more prevalent in older patients, those with a 2nd transplant and in patients with polycystic kidney disease as their primary renal disease. The postoperative hospital stay, rejection within the 1st year, and 1-year mortality rate are increased in patients with an inotropic score ≥7.

Influence of hemodynamics and intra-operative hydration on biochemical outcome of renal transplant recipients

BACKGROUND AND AIMS

Early graft function is crucial for successful kidney transplantation. The aim of our study was to evaluate the effect of intra-operative central venous pressure (CVP) and mean arterial pressure (MAP) on early graft function and biochemical outcome.

MATERIAL AND METHODS

This was a retrospective study carried out on patients undergoing renal transplant only from live-related donors between March 2011 and May 2013. We mainly divided the patients into two groups based on CVP and mean MAP. One group had CVP more than 12 and other with CVP <12 mmHg at the time of declamping. Further one group was with mean MAP >100 mmHg and other with mean MAP of <100 mmHg. The graft outcome of genetically related and genetically unrelated donors was also evaluated in early postoperative period. The trend in fall of serum creatinine was studied during the first five post-operative days. The effect of age, dry weight, sex, relation with donor and intraoperative factors like MAP and CVP on early graft function were analysed. Correlation analysis, analysis of variance test (ANOVA) and multivariate analysis technique were used in this study for statistical computation.

RESULTS

The mean CVP at the time of declamping was 13.91 mmHg. The minimum CVP was 6 mmHg in one patient who had ischemic heart disease with low ejection fraction. All 5 days mean serum creatinine values were comparable in two groups on 1(st), 2(nd), 3(rd) and 4(th) postoperative days. The mean MAP at the time of declamping was 111.22 mmHg. Mean MAP varied from a minimum of 95 mmHg to maximum of 131 mmHg. There was no significant difference in two groups on 1(st), 2(nd), 3(rd), 4(th) and 5(th) postoperative days.

CONCLUSION

A CVP around 12 mmHg and mean MAP >95 mmHg with good perioperative fluid hydration is associated with good early graft function.

Preconditioning renoprotective effect of isoflurane in a rat model of virtual renal transplant

BACKGROUND

The development of warm-cold ischemia-reperfusion (IR) injury of the kidney grafts is inevitable during renal transplantation. However, there is currently no definite renoprotective strategy available in the protection of the graft tissue. In the present study, we compared the renal protection of preconditioning isoflurane with N-acetylcysteine (NAC) in a novel rat model of warm-cold renal IR injury.

MATERIALS AND METHODS

Adult Sprague-Dawley rats were randomly assigned to receive inhaled isoflurane (1.5% for 2 h), NAC (1 g/kg, intra-arterial injection) or placebo before the induction of brief warm ischemia (10 min) followed by cold ischemia (45 min) periods. Plasma levels of creatinine and tissue inflammatory reaction in the kidney were analyzed 72 h after reperfusion.

RESULTS

Elevated plasma level of creatinine and urea indicated the development of acute renal injury secondary to IR injury. The creatinine levels were reduced in animals pretreated with inhaled isoflurane and NAC, and the level was more significantly decreased in the isoflurane-treated group. Preconditioning with volatile isoflurane also significantly suppressed the tissue myeloperoxidase activity and expression of the inducible nitric oxide synthase. Immunostaining confirmed that myeloperoxidase expression was most significantly attenuated in the glomerulus and peritubular capillaries of rats pre-exposed to isoflurane.

CONCLUSIONS

We present the first study demonstrating that the administration of volatile isoflurane before induction of experimental warm-cold renal IR injury provides preconditioning renoprotective effect, which is superior to the treatment with NAC. The beneficial renoprotective effect of isoflurane is most likely mediated by attenuation of proinflammatory reaction in the injured kidney.

Hyperkalemia by Euro-Collins solution in anesthesia for renal transplantation: a case report

OBJECTIVE

To describe anesthesia for renal transplantation that progressed to a sharp potassium increase after kidney reperfusion with Euro-Collins' solution in the operative field. We will also report on diagnosis and treatment used.

CONCLUSION

The use of infusion solutions in the surgical field requires careful monitoring, such as electrocardiography, measurement of serum potassium, and availability of calcium gluconate, insulin, and albuterol for immediate use. The replacement of Euro-Collins' solution for saline solution immediately before the implant may be a useful option in patients with high levels of potassium.

Interactions between hemodynamics and pharmacology in kidney transplantation

INTRODUCTION

Renal transplantation (RT) is considered the treatment of choice for patients with end-stage renal disease due to the improved short- and long-term survival benefits over dialysis treatment. The success of RT can be improved by working within a multidisciplinary team.

OBJECTIVE

The aim of this work was to assess the anesthetic management of RT to guarantee success.

DISCUSSION

Anesthesiologists who work in RT should know the interactions between hemodynamics and pharmacology in these patients. But to be able to work as a team, there are three questions that need to be answered: What do the urologist and the anesthesiologist need to know about renal transplantation? What does the urologist need to know about anesthesia? Or, in other words, what do anesthesiologists really want the urologists to know, and what does an anesthesiologist want to know about RT?

CONCLUSIONS

RT is a complex procedure that needs a multidisciplinary approach, especially in patients with important comorbidities. It is necessary to learn how to look through the eyes of the rest of the team. Working within a multidisciplinary team is basic to ensure the success of the RT.