Predictors of renal function recovery among patients undergoing renal replacement therapy following orthotopic liver transplantation

The type, duration, and severity of pretransplant kidney injury predict prolonged kidney dysfunction after liver transplantation

Chronic kidney disease (CKD) is a major complication of liver transplantation (LT) associated with substantial morbidity and mortality. Knowing the drivers of post-LT kidney dysfunction-with a granular focus on the type, duration, and severity of pre-LT kidney disease-can highlight intervention opportunities and inform dual-organ allocation policies. We retrospectively analyzed predictors of safety net kidney after liver transplant (KALT) eligibility and kidney replacement therapy (KRT) for > 14 days after LT. Among 557 recipients of adult deceased-donor LT, 49% had normal kidney function, 25% had acute kidney injury (AKI), and 25% had CKD±AKI at the time of LT. A total of 36 (6.5%) qualified for KALT and 63 (11%) required KRT > 14 days. In univariable analysis, factors associated with KALT eligibility and KRT > 14 days, respectively, included stage 3 AKI (OR 7.87; OR 7.06), CKD±AKI (OR 4.58; OR 4.22), CKD III-V duration (OR 1.10 per week; OR 1.06 per week), and increasing CKD stage (stage III: OR 3.90, IV: OR 5.24, V: OR 16.8; stage III: OR 2.23, IV: OR 3.62, V: OR 19.4). AKI stage I-II and AKI duration in the absence of CKD were not associated with the outcomes. Pre-LT KRT had a robust impact on KALT eligibility (OR 4.00 per week) and prolonged post-LT KRT (OR 5.22 per week), with 19.8% of patients who received any pre-LT KRT ultimately qualifying for KALT. Eligibility for KALT was similar between those who received 0 days and ≤ 14 days of KRT after LT (2.1% vs. 2.9%, p = 0.53). In conclusion, the type, duration, and severity of pre-LT kidney dysfunction have unique impacts on post-LT kidney-related morbidity, and future research must use these novel classifications to study mitigation strategies.

Continuous Renal Replacement Therapy after Liver Transplantation: Peri-Operative Associated Factors and Impact on Survival

Continuous renal replacement therapy (CRRT) following orthotopic liver transplantation (OLT) is usually started for multifactorial reasons, with variable incidence among series. This paper presents a single-center retrospective observational study on the early use (within one week) of CRRT after consecutive cadaveric OLT from January 2008 to December 2016. Preoperative patient characteristics and intraoperative data were collected, and patients were divided into two groups (CRRT and no CRRT) to explore the factors associated with the use of CRRT. Repeated measurements of postoperative creatinine were analyzed with generalized estimating equation (GEE) models. Among 528 OLT patients, 75 (14.2%) were treated with CRRT at least once in the first week. Patients treated with CRRT showed lower survival in a Kaplan−Meier curve (log-rank p value < 0.01). Patients treated with CRRT had a more severe preoperative profile, with a significantly higher age, MELD, BUN, creatinine, and total bilirubin, as well as a longer surgery time and a higher number of transfusions of red blood cells, plasma, and platelets (all p values < 0.05). In a stepwise multiple analysis, the following characteristics remained independently associated with the use of CRRT: the MELD score OR 1.12 (95% CL: 1.07−1.16), p value < 0.001, and the preoperative value for blood urea nitrogen OR 1.016 (95% CL: 1.010−1.023), p value < 0.001. The early use of CRRT after OLT occurred at a low rate in this large cohort; however, it was associated with worse outcomes. Apart from the preoperative severity, repeated intraoperative hypotension episodes, which were likely modifiable or preventable, were associated with the increased use of CRRT and higher postoperative creatinine.

Chronic Kidney Disease After Liver Transplantation: Impact of Extended Criteria Grafts

The use of extended criteria donor (ECD) grafts has been associated with acute kidney injury (AKI) after liver transplantation. However, the relation between graft quality and development of chronic kidney disease (CKD) remains unknown. Therefore, the aim of this study was to analyze the impact of ECD grafts for CKD after liver transplantation. All patients (2007-2015) transplanted for end-stage liver disease at our center were assessed. Longterm kidney function was divided into 4 groups: no CKD (estimated glomerular filtration rate [eGFR], ≥60 mL/minute/1.73 m² ), mild CKD (eGFR, 30-59 mL/minute/1.73 m² ), severe CKD (eGFR, 15-29 mL/minute/1.73 m² ), and end-stage renal disease (ESRD). Marginal donation after brain death (DBD) grafts (donor age, >70 years; body mass index, >35 kg/m² ; cold storage, >12 hours) and donation after circulatory death (DCD) grafts were considered ECD grafts. Overall, 926 patients were included, and 43% received an ECD graft (15% marginal DBD; 28% DCD). After 5 years, 35% developed CKD; severe CKD and ESRD occurred in only 2% and 1%, respectively. CKD rates were comparable for all 3 graft groups (standard group, 36%; marginal DBD group, 29%; DCD group, 35%; standard versus marginal DBD groups, P = 0.16; standard versus DCD group, P = 0.80). None of the ECD criteria were identified as independent risk factors in a Cox regression model for CKD. Risk factors included recipient age, female sex, and preoperative kidney function. Furthermore, recipients who had severe acute kidney injury (AKI; Kidney Disease: Improving Global Outcomes stages 2 and 3) had a 1.8-fold increased risk for CKD. Longterm kidney function of recipients with severe AKI depended on the recovery of kidney function in the first postoperative week. In conclusion, there is no direct relation between the use of ECD grafts and CKD after liver transplantation. However, caution should be taken in recipients who experience severe AKI, regardless of graft type.

Intraoperative Management to Prevent Cardiac Collapse in a Patient With a Recurrent, Large-volume Pericardial Effusion and Paroxysmal Atrial Fibrillation During Liver Transplantation: A Case Report

BACKGROUND

Pericardial effusion is a common feature of end-stage liver disease. In this case report we describe the intraoperative management of recurrent pericardial effusion, without re-pericardiocentesis, to prevent circulatory collapse during a critical surgical time-point; that is, during manipulation of the major vessels and graft reperfusion.

METHODS

A 47-year-old woman with hepatitis B was scheduled to undergo deceased donor liver transplantation (LT). A large pericardial effusion was preoperatively identified using transthoracic echocardiography (TTE). The patient also had paroxysmal atrial fibrillation. Two days before surgery, preemptive pericardiocentesis was performed and the 1150-mL effusion was drained. Intraoperatively, recurrence of the large pericardial effusion was identified using transesophageal echocardiography (TEE). During inferior vena cava manipulation, the surgeon consulted the anesthesiologist to evaluate the hemodynamic changes in the patient. After 3 attempts, the transplant team was able to determine the most appropriate anastomosis site, defined as that with the least impact on cardiac function. To prevent the development of severe postreperfusion syndrome, 10% MgSO₄ (2 g) was gradually infused 20 minutes before portal vein declamping, and immediately before graft reperfusion a 100-μg bolus of epinephrine was administered.

RESULTS

During graft reperfusion, there was no evidence of heart chamber collapse or flow disturbance, as seen on the TEE findings. Postoperatively, the patient recovered completely and was discharged from the hospital. Six months after surgery, there was no sign of pericardial effusion on follow-up TTE.

CONCLUSION

Our intraoperative strategy may prevent cardiac collapse in patients with pericardial effusion detected during LT. Intraoperative TEE plays an important role in guiding hemodynamic management.

Relation of Preoperative and Postoperative Echocardiographic Parameters With Rejection and Mortality in Liver Transplant Patients

OBJECTIVES

Survival in liver transplant after end-stage liver disease is associated with major cardiac functions. In a significant number of patients with end-stage liver disease, cardiac dysfunctions may be observed, which can include high-output heart failure, cardiac valve disease, and pulmonary venous and arterial hypertension. All of these affect perioperative survival. The aim of our study was to determine whether preoperative and postoperative echocardiographic parameters, specifically right heart-related tricuspid regurgitation, estimated systolic pulmonary arterial pressure, and tricuspid annular plane systolic excursion, are associated with rejection and mortality in liver transplant patients.

MATERIALS AND METHODS

Adult patients (> 18 years old) who underwent liver transplant at our center between January 2011 and March 2017 were included in the study, with 64 patients retrospectively screened. The echocardiographic images that were taken immediately before and immediately after liver transplant were evaluated. The patients were divided into 2 groups according to rejection data and mortality. All parameters were analyzed for both variables.

RESULTS

For the 24 patients with liver rejection and 40 patients without liver rejection, there were no statistically significant differences in terms of demographic data, echocardiographic parameters, and laboratory data. However, when patients were evaluated according to survival, there was a statistically significant difference between these 2 groups concerning the echocardiography parameters of systolic pulmonary arterial pressure (P = .005), tricuspid annular plane systolic excursion (P = .001), and postoperative right ventricular width (P = .01).

CONCLUSIONS

Echocardiography, being a simple and easily accessible technique that is reliable in excluding pulmonary hypertension diagnosis, can be used as a guide in the evaluation of right ventricular function and tricuspid regurgitation, particularly in patients who are not hemodynamically stable before and after liver transplant.