Perioperative blood transfusion decreases long-term survival in pediatric living donor liver transplantation

ARTICLE HIGHLIGHTS

Research background

Pediatric living donor liver transplantation (PLDLT) is a multidisciplinary procedure of high complexity and potential risk of bleeding. The association between transfusion and short- and long-term postoperative complications is poorly established especially in small children. Blood transfusion is frequently indicated in the perioperative period of liver transplant, though there is little robust evidence of associated postoperative complications. Given the good survival results, in the past decade, it is now necessary to identify risk factors for complications in order to improve the long-term evolution.

Research motivation

To study in depth the short- and long-term evolution of this specific group of highly fragile pediatric patients, in order to improve the proficiency acquired in 20 years of working with PLDLT, and to be able to share knowledge.

Research objectives

This study assessed whether perioperative transfusion is associated with early and late postoperative complications and mortality in small patients undergoing PLDLT.

Research methods

Postoperative complications along 10 years of follow up were graduated with Clavien-Dindo modified classification in order to assess relationship between blood transfusion and postoperative complications. Multiple logistic regression analysis identified risk factors for major postoperative complications. Perioperative red blood cells volume was identified as a single risk factor and a receiver operating characteristic curve identified a cutoff point of 27.5 mL/kg. Cox regression analyses identified independent risk factors for mortality. Overall patient and graft survival analyses was performed using Kaplan–Meier survival curves, which were compared using the log-rank test and a P < 0.05 was considered statistically significant.

Research results

In terms of red blood cells (RBC) transfusion volume, there was a significantly higher rate of 30 d reoperation (26.3% × 8.7%, P < 0.001) and 30 d mortality rate (6.6% × 0.0%, P < 0.001) in the high-volume transfusion (HTr) vs low-volume transfusion (LTr), respectively. Early liver transplantation (LT)-specific complications include primary non-function, biliary complications, vascular thrombosis, and retransplantation that were not related to a higher perioperative transfusion volume. Over 10 years of follow-up, with respect to RBC transfusion volume, there was a significantly higher rate of reoperation (36.5% × 12.6%, P < 0.001) and mortality (25.5% × 7.8%, P < 0.001), respectively, in the HTr compared to the LTr. Perioperative RBC volume > 27.5 mL/kg and preoperative estimated glomerular filtration rate were identified as independent risk factors for mortality over 10 years of follow-up after LT. The patient survival rates were significantly lower in the HTr than in the LTr at 1, 5, and 10 years post-LT: 82.7% vs 97.7%, 73.9% vs 93.8%, and 72.6% vs 90.9%, respectively. Likewise, the graft survival rates were significantly lower in the HTr than in the LTr at 1, 5, and 10 years post-LT: 79.5% vs 97.7%, 67.2% vs 92.3%, and 67.2% vs 87%, respectively.

Research conclusions

A perioperative RBC transfusion volume > 27.5 mL/kg is associated with not only increased rates of infectious, cardiovascular, respiratory, and neoplastic complications but also decreased frequency of rejection episodes. Furthermore, a perioperative volume of RBC transfusion higher than 27.5 mL is an independent risk factor for mortality, and is directly related to reduced patient and graft survival in PLDLT.

Research perspectives

The detailed analysis of this study allows the construction of strategy protocols to reduce the need for transfusion of patients undergoing PLDLT improving short- and long-term outcome.