Association Between Post-Operative Serum Lactate, Fluid Administration, and Outcome in Living Donor Liver Transplant Recipients: A Ten-Year Experience

BackgroundFor some liver transplant recipients, elevated lactate after transplantation is associated with early allograft dysfunction (EAD). Determining which patients with elevated lactate will develop EAD is a challenge because lactate can accumulate due to increased production, decreased hepatic clearance, or both. Intravenous fluid administration may be beneficial for patients with elevated lactate who have insufficient intravenous circulating vascular volume, or it may result in vascular volume overload and allograft injury from congestion for patients who have adequate perfusion and no signs of shock. We hypothesized that in absence of other signs of shock, intravenous fluid administration would not be associated with improved graft function for patients with elevated post-transplant lactate.MethodsWe performed a single-center cohort study of living donor liver transplant recipients between March 2009-June 2018 (n = 197). We categorized the study population based on the highest lactate in the first 6 h of the post-transplant ICU stay (Group 1: < 3 mmol/L; Group 2: 3-6 mmol/L and Group 3: > 6 mmol/L). Our primary exposure was post-transplant ICU intravenous fluid administration and primary outcome was EAD.ResultsSixty- four (32.5%) patients developed EAD: 24 (26.7%) in Group 1, 21 (29.6%) in Group 2 and 19 (52.8%) in Group 3. Within group 2, there was no difference between EAD and non-EAD patients in baseline characteristics, vasopressor use at two hours, or urine output. In a linear mixed model in Group 2 patients, there was a significant difference in the mean fluid intake during the first 36 h of ICU stay for those who developed EAD compared to those who did not (EAD: 826 ± 56 ml vs non-EAD: 680 ± 39 ml respectively, p = 0.03).ConclusionOur results show that elevated lactate after liver transplant is frequently caused by decreased lactate clearance. Following liver transplantation, intensivists should interpret elevated lactate levels in clinical context before administering intravenous fluids.