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

Haemodynamic effect of dexmedetomidine during paediatric kidney transplantation

BACKGROUND

Dexmedetomidine is increasingly used for its ability to stabilise haemodynamic status during general anaesthesia. However, there is currently no data on paediatric kidney transplant recipients (pKTR). This study investigates the haemodynamic impact of dexmedetomidine administered perioperatively in pKTR.

METHODS

From 2019 to 2023, a retrospective study was conducted at Nantes University Hospital involving all pKTR under 18 years of age. The study compared intraoperative haemodynamic parameters between patients administered dexmedetomidine during kidney transplantation (DEX group) and those who did not receive it (no-DEX group). Mean arterial pressure (MAP) and heart rate (HR) were monitored throughout the duration of anaesthesia and compared. Graft function was assessed based on creatinine levels and glomerular filtration rate (GFR) at specific intervals. The perioperative use of fluids and vasoactive drugs, as well as their administration within 24 h post-surgery, were analysed.

RESULTS

Thirty-eight patients were enrolled, 10 in the DEX group and 28 in the no-DEX group. Intraoperative HR was similar between the groups; however, MAP was higher in the DEX group (mean difference 9, standard deviation (SD, 1-11) mmHg, p = 0.039). No differences were found regarding the use of fluid and vasoactive drug therapy between groups. GFR at 1 month post-transplantation was significantly elevated in the DEX group (p = 0.009).

CONCLUSIONS

pKTR receiving intraoperative dexmedetomidine exhibited higher perioperative MAP compared to those not administered dexmedetomidine. Additionally, the DEX group demonstrated superior graft function at 1 month. The direct impact of dexmedetomidine on immediate postoperative graft function in pTKR warrants further investigation in a prospective multicentre randomised study.

Effect of perioperative management on early graft function in living donor paediatric kidney transplantation

BACKGROUND

Paediatric kidney transplantation has an increased risk of surgical and vascular complications, with intensive care monitoring required postoperatively. This study aimed to determine if perioperative management affects early graft function in living donor paediatric kidney transplantation.

METHODS

Clinical data was extracted from the electronic medical record for living donor kidney transplants at two paediatric centres covering the state of New South Wales (NSW), Australia from 2009 to 2021. Estimated glomerular filtration rate (eGFR) of 7 days and 1-month post-transplant were calculated as measures of early graft function.

RESULTS

Thirty-nine eligible patients (female n (%) 13 (33%)) with a median (IQR) age of 6 (3-9) years and pre-transplant eGFR of 7 (6-10) mL/min/1.73 m2 were analysed. Mean (SD) central venous pressure (CVP) after revascularisation was 11 (4) mmHg. Intraoperatively, mean volume of fluid administered was 84 (39) mL/kg, and 34 (87%) patients received vasoactive agents. Average systolic blood pressure (BP) in the first 24-h post-transplant was 117 (12) mmHg. Postoperatively, median volume of fluid administered in the first 24 h was 224 (159-313) mL/kg, and 17 (44%) patients received vasoactive agents. Median eGFR 7 days and 1-month post-transplant were 115 (79-148) and 103 (83-115) mL/min/1.73 m2, respectively. Linear regression analyses demonstrated that after adjusting for age, the average CVP after revascularisation and average systolic BP in the first 24-h post-transplant were not associated with eGFR in the first month post-transplant.

CONCLUSIONS

Targeted intraoperative and postoperative fluid and haemodynamic characteristics were achieved but did not correlate with early graft function.

Intraoperative management of pediatric renal transplant recipients: An opportunity for improvement

BACKGROUND

Optimal organ perfusion at the time of pediatric renal transplantation is a commonly agreed upon goal. Intraoperative conditions such as fluid balance and arterial pressure determine the success of this goal. Sparse literature guides the anesthesiologist in accomplishing this. We, therefore, hypothesized that significant variability exists in the methods used to optimize renal perfusion during transplantation.

METHODS

A literature search was performed to assess what guidelines currently exist to optimize intraoperative renal perfusion. The intraoperative practice pathways of six large children's hospitals in North America were obtained to compare suggested guidelines. A retrospective chart review of anesthesia records was performed of all pediatric renal transplants over 7 years at the University of North Carolina.

RESULTS

There did not appear to be agreement between the various publications in terms of standard intraoperative monitoring, specific blood pressure or central venous pressure goals, and fluid management. The practice pathways of six children's hospitals showed significant variation and lack of a consensus-driven approach. The chart review demonstrated significant variation between anesthesiologists in terms of invasive monitoring, fluid management, hemodynamic goals, vasopressor use, and analgesic choices. However, children <30 kg were significantly more likely to have arterial lines and epidural catheters placed prior to surgery.

CONCLUSION

Significant variation exists across centers of expertise and even within centers of expertise with regard to the intraoperative management of pediatric kidney transplant recipients. In the era of enhanced recovery after surgery, this presents an opportunity to develop consensus on an evidence-based approach to optimize initial organ perfusion during surgery.

Recommendations for living donor kidney transplantation

This Guide for Living Donor Kidney Transplantation (LDKT) has been prepared with the sponsorship of the Spanish Society of Nephrology (SEN), the Spanish Transplant Society (SET), and the Spanish National Transplant Organization (ONT). It updates evidence to offer the best chronic renal failure treatment when a potential living donor is available. The core aim of this Guide is to supply clinicians who evaluate living donors and transplant recipients with the best decision-making tools, to optimise their outcomes. Moreover, the role of living donors in the current KT context should recover the level of importance it had until recently. To this end the new forms of incompatible HLA and/or ABO donation, as well as the paired donation which is possible in several hospitals with experience in LDKT, offer additional ways to treat renal patients with an incompatible donor. Good results in terms of patient and graft survival have expanded the range of circumstances under which living renal donors are accepted. Older donors are now accepted, as are others with factors that affect the decision, such as a borderline clinical history or alterations, which when evaluated may lead to an additional number of transplantations. This Guide does not forget that LDKT may lead to risk for the donor. Pre-donation evaluation has to centre on the problems which may arise over the short or long-term, and these have to be described to the potential donor so that they are able take them into account. Experience over recent years has led to progress in risk analysis, to protect donors' health. This aspect always has to be taken into account by LDKT programmes when evaluating potential donors. Finally, this Guide has been designed to aid decision-making, with recommendations and suggestions when uncertainties arise in pre-donation studies. Its overarching aim is to ensure that informed consent is based on high quality studies and information supplied to donors and recipients, offering the strongest possible guarantees.

A Software-Guided Approach to Hemodynamic Management in a Renal Transplant Recipient: A Case Report

The function of renal allografts in the perioperative period is partly dependent on minimizing hemodynamic instability. We have developed hemodynamic monitoring software-named the "pressure field"-that was utilized in a 68-year-old high-risk kidney transplant recipient. The "pressure field" was used to individualize fluid and drug administration and replicate the preoperative hemodynamics. The patient received net zero fluid intraoperatively and had an uneventful postoperative course. We found the pressure field method helpful to manage perioperative hemodynamics in this high-risk patient.

Perioperative anesthesia care for the pediatric patient undergoing a kidney transplantation: An educational review

Living-donor kidney transplantation is the first choice therapy for children with end-stage renal disease and shows good long-term outcome. Etiology of renal failure, co-morbidities, and hemodynamic effects, due to donor-recipient size mismatch, differs significantly from those in adult patients. Despite the complexities related to both patient and surgery, there is a lack of evidence-based anesthesia guidelines for pediatric kidney transplantation. This educational review summarizes the pathophysiological changes to consider and suggests recommendations for perioperative anesthesia care, based on recent research papers.

Pediatric kidney transplantation, a technical update

PURPOSE OF REVIEW

Pediatric kidney transplantation is the definitive therapy for infants and children suffering from renal failure. It is a distinct endeavor demanding specialized care for optimal results. This includes a dedicated preoperative workup accounting for unique predisposing urologic conditions, specialized surgical techniques, and careful hemodynamic monitoring and maintenance.

RECENT FINDINGS

Historically, size-matched renal allografts from pediatric donors to pediatric recipients suffered from poor outcomes. Advances in surgical technique performed at high volume centers have shown that these operations can be performed safely, helping expand the donor pool for these patients. Concurrently, transplantation of increasingly small for size infants with complex medical and surgical backgrounds has become a reality.

SUMMARY

On a policy front, efforts to expand access to size-matched organs, combined with advances in medical management and immunosuppression have seen pediatric renal transplantation reach new heights. Now, these breakthroughs are heightened by the ability to transplant such organs into the smallest infants. The net result will be diminished transplant waiting times and, accordingly, improved quality of life and longevity for children suffering from renal failure.

Malignant hyperthermia during pediatric kidney transplantation-A medical and ethical quandary

Malignant hyperthermia (MH) is a rare life-threatening anesthetic complication with high mortality rates. MH during adult kidney transplant has been reported previously. However, the occurrence of MH after multiple previous uneventful anesthetic exposures in a pediatric kidney transplant recipient is rare. To our knowledge, this is the first reported case of MH in a child undergoing a live donor kidney transplant. The approaches for addressing perioperative challenges and ethical dilemmas to ensure successful outcomes are described. The recipient, a 5-year-old male child, weighing 20 kg, with a history of multiple previous uneventful anesthetic exposures, underwent live donor kidney transplant for end-stage renal disease (ESRD). Post-reperfusion he developed fulminant MH with rapidly progressing hyperthermia, hypercarbia, tachycardia, and muscle rigidity, which in addition to complicating the medical management raised several ethical issues as well. MH was successfully managed with dantrolene and other supportive measures. Judicious use of inotropes and fluids helped maintain stable hemodynamics and graft perfusion. Management of MH is complicated in a pediatric patient with ESRD undergoing live donor kidney transplant. Preference for non-depolarizing muscle relaxants instead of succinylcholine during endotracheal intubation can result in delayed onset of clinical manifestations. However, the metabolic complications may be more severe due to preexisting electrolyte and acid-base disturbances. Maintaining optimal graft perfusion while simultaneously combating MH can be very challenging in a child. Since the allograft is a precious commodity, critical decisions regarding the harvesting of the donor kidney need to be well thought out. Early diagnosis and prompt treatment with dantrolene are critical to preserving graft function and the recipient's life.

Recipient pre-existing chronic hypotension is associated with delayed graft function and inferior graft survival in kidney transplantation from elderly donors

BACKGROUND

Pre-existing chronic hypotension affects a percentage of kidney transplanted patients (KTs). Although a relationship with delayed graft function (DGF) has been hypothesized, available data are still scarce and inconclusive.

METHODS

A monocentric retrospective observational study was performed on 1127 consecutive KTs from brain death donors over 11 years (2003-2013), classified according to their pre-transplant Mean Blood Pressure (MBP) as hypotensive (MBP < 80 mmHg) or normal-hypertensive (MBP ≥ 80 mmHg, with or without effective antihypertensive therapy).

RESULTS

Univariate analysis showed that a pre-existing hypotension is associated to DGF occurrence (p<0.01; OR for KTs with MBP < 80 mmHg, 4.5; 95% confidence interval [CI], 2.7 to 7.5). Chronic hypotension remained a major predictive factor for DGF development in the logistic regression model adjusted for all DGF determinants. Adjunctive evaluations on paired grafts performed in two different recipients (one hypotensive and the other one normal-hypertensive) confirmed this assumption. Although graft survival was only associated with DGF but not with chronic hypotension in the overall population, stratification according to donor age revealed that death-censored graft survival was significantly lower in hypotensive patients who received a KT from >50 years old donor.

CONCLUSIONS

Our findings suggest that pre-existing recipient hypotension, and the subsequent hypotension-related DGF, could be considered a significant detrimental factor, especially when elderly donors are involved in the transplant procedure.

Effect of Perioperative Optimization of Arterial Oxygen Content and Perfusion Pressure on the Function of the Transplanted Kidney in the Retrospective Study of Excretory Function and Assessment of New Markers of Kidney Damage: IL-18, Neutrophil Gelatinase-Associated Lipocalin, and Clusterin

INTRODUCTION

The concept of anesthesia, in which kidney perfusion is optimized, the use of nephrotoxic drugs is avoided, and general anesthesia with protective and preconditioning properties of the graft is applied, is a key element of the therapeutic strategy in kidney transplantation (KTx).

MATERIAL AND METHOD

A total of 86 patients (mean age: 49.4 ± 14.0 years, 66% men) with end-stage renal disease who underwent KTx between 2012 and 2015 were included in this retrospective study. Our aim was to assess the effect of oxygen content in arterial blood and selected hemodynamic parameters on the graft function and the occurrence of delayed graft failure.

RESULTS

No differences were found in baseline characteristics, indication for transplantation, and surgical technique used among study population. No correlation was found between oxygen delivery exponents and both standard markers of renal function and new biochemical markers (eg, IL-18, clusterin, and neutrophil gelatinase-associated lipocalin [NGAL]).

DISCUSSION

In our study, hemodynamic parameters measured at scheduled intervals did not exceed the physiological range, which might have been the reason for the lack of correlation between the function of graft and the described hemodynamic conditions. At the same time, in the observed ranges of perfusion pressure during optimization of the oxygen content, no correlations were found with the postoperative function of the transplanted kidney. That observation could be a valuable conclusion for reducing the tendency of maintaining high blood pressure with the abuse of catecholamines, especially vasoconstrictors, and volume therapy, whose negative effect on tissue perfusion is unequivocal.

Assessment of Hemoglobin Levels in Patients Qualified for Kidney Transplantation in the Perioperative Period and Its Impact on the Occurrence of Delayed Graft Function

BACKGROUND

Anesthesia in patients undergoing kidney transplantation (KTx) should be aimed at creating optimal hemodynamic conditions for the newly implanted kidney. Changes in of blood count, caused mainly by intraoperative hemodilution, may adversely affect the perioperative course by strengthening the pathologic mechanisms of ischemia-reperfusion syndrome.

METHODS

A total of 86 patients (mean age: 49.4 ± 14.0 years, 66% men) with end-stage renal disease who underwent KTx between 2012 and 2015 were included in this retrospective study. Our aim was to assess the hemoglobin level and the effect of fluctuations caused by the implemented fluid therapy on graft function and the occurrence of delayed graft failure.

RESULTS

There was no difference in baseline characteristics, indication for transplantation, and surgical technique used among study population. Among the whole observation group, no correlation was found between fluid therapy causing hemodilution with a decrease in hemoglobin concentration and the occurrence of delayed graft failure.

CONCLUSIONS

In our observations, we paid special attention to the problem of hemodilution in patients undergoing KTx. It is important to emphasize the importance of proper preparation of the patient for KTx by earlier implementation of anemia therapy, thus preventing exacerbation of anemia in the postoperative period, especially because the perioperative use of blood products is associated with numerous complications and a worse prognosis for the newly implanted kidney.

Cardiac output-guided hemodynamic therapy for adult living donor kidney transplantation in children under 20 kg: A pilot study

BACKGROUND

A living-donor (adult) kidney transplantation in young children requires an increased cardiac output to maintain adequate perfusion of the relatively large kidney. To achieve this, protocols commonly advise liberal fluid administration guided by high target central venous pressure. Such therapy may lead to good renal outcomes, but the risk of tissue edema is substantial.

AIMS

We aimed to evaluate the safety and feasibility of the transpulmonary thermodilution technique to measure cardiac output in pediatric recipients. The second aim was to evaluate whether a cardiac output-guided hemodynamic therapy algorithm could induce less liberal fluid administration, while preserving good renal results and achieving increased target cardiac output and blood pressure.

METHODS

In twelve consecutive recipients, cardiac output was measured with transpulmonary thermodilution (PiCCO device, Pulsion). The algorithm steered administration of fluids, norepinephrine and dobutamine. Hemodynamic values were obtained before, during and after transplantation. Results are given as mean (SD) [minimum-maximum].

RESULTS

Age and weight of recipients was 3.2 (0.97) [1.6-4.9] yr and 14.1 (2.4) [10.4-18] kg, respectively. No complications related to cardiac output monitoring occurred. After transplantation, cardiac index increased with 31% (95% CI = 15%-48%). Extravascular lung water and central venous pressure did not change. Fluids given decreased from 158 [124-191] mL kg^-1 in the first 2 patients to 80 (18) [44-106] mL kg^-1 in the last 10 patients. The latter amount was 23 mL kg^-1 less (95% CI = 6-40 mL kg^-1 ) than in one recent study, but similar to that in another. After reperfusion, all patients received norepinephrine (maximum dose 0.45 (0.3) [0.1-0.9] mcg kg^-1  min^-1 ). Patient and graft survivals were 100% with excellent kidney function at 6 months post-transplantation.

CONCLUSION

Transpulmonary thermodilution-cardiac output monitoring appeared to be safe and feasible. Using the cardiac output-guided algorithm led to excellent renal results with a trend toward less fluids in favor of norepinephrine.

A survey of the anesthetic management of pediatric kidney transplantation in France

BACKGROUND

Renal transplantation is the best available therapeutic option for end-stage renal failure in both children and adults. However, little is known about anesthetic practice during pediatric renal transplantation.

MATERIAL AND METHODS

The study consisted of a national survey about anesthetic practice during pediatric renal transplantation in France. French tertiary pediatric centers performing renal transplants were targeted, and one physician from each team was asked to complete the survey. The survey included patient data, preoperative assessment and optimization data, and intraoperative anesthesia data (drugs, ventilation, and hemodynamic interventions).

RESULTS

Twenty centers performing kidney transplantation were identified and contacted to complete the survey, and eight responded. Surveyed centers performed 96 of the 122 pediatric kidney transplantations performed in France in 2017 (79%). Centers consistently performed echocardiography and ultrasound examinations of the great veins preoperatively and consistently employed esophageal Doppler cardiac output estimation and vasopressors intraoperatively. All other practices were found to be heterogeneous. Central venous pressure was monitored in six centers, and dopamine was administered perioperatively in two centers.

CONCLUSIONS

The current study provides a snapshot of the perioperative management of pediatric kidney transplantation in France. Results emphasize the need for both standardization of practice and awareness of recent evidence against the use of CVP monitoring and dopamine infusions.

Modifiable Risk Factors for Delayed Graft Function After Deceased Donor Kidney Transplantation

PURPOSE

Delayed graft function is a major complication after kidney transplantation affecting patients' long-term outcome. The aim of this study was to identify modifiable risk factors for delayed graft function after deceased donor kidney transplantation.

METHODS

This is a single-center retrospective cohort study of a university transplantation center. Univariate and multivariate step-wise logistic regression analysis of patient-specific and procedural risk factors were conducted.

RESULTS

We analyzed 380 deceased donor kidney transplantation patients between October 30, 2008 and December 30, 2017. The incidence of delayed graft function was 15% (58/380). Among the patient-specific risk factors recipient diabetes (2.8 [1.4-5.9] odds ratio [OR] [95% confidence interval [CI]]), American Society of Anesthesiologist score of 4 (2.7 [1.2-6.5] OR [95% CI]), cold ischemic time >13 hours (2.8 [1.5-5.3] OR [95% CI]) and donor age >55 years (1.9 [1.01-3.6] OR [95% CI]) revealed significance. The significant intraoperative, procedural risk factors included the use of colloids (3.9 [1.4-11.3] OR [95% CI]), albumin (3.0 [1.2-7.5] OR [95% CI]), crystalloids >3000 mL (3.1 [1.2-7.5] OR [95% CI]) and mean arterial pressure <80 mm Hg at the time of reperfusion (2.4 [1.2-4.8] OR [95% CI]).

CONCLUSION

Patients undergoing deceased donor kidney transplantation with a mean arterial pressure >80 mm Hg at the time of transplant reperfusion without requiring excessive fluid therapy in terms of colloids, albumin or crystalloids >3000 mL are less likely to develop delayed graft function.