Perioperative severe hemorrhage in pediatric kidney transplantation: frequency, risk factors, and outcomes

To characterize severe hemorrhage and determine its frequency, risk factors, and consequences in the perioperative period of pediatric kidney transplantation.

Single-center retrospective study of children undergoing their first kidney transplant between 2008 and 2015. Severe hemorrhage was defined using a data-driven cluster analysis to identify patients with high perioperative bleeding volume and blood component requirements. Additionally, severe hemorrhage was defined by the need for reoperation or administration of activated factor VII or fibrinogen for bleeding related to transplant. Thirty-eight exposure variables were examined, including clinical and laboratory data, donor and recipient characteristics, surgical technical variables, and medications. Analysis of hemorrhage consequences considered the occurrence of delayed renal function, hospitalization length during transplantation, estimated glomerular filtration rate post-transplantation, and five-year graft and patient survival.

Severe hemorrhage occurred in 16/218 cases (7.3%). In unadjusted logistic analyses, higher risk was observed among younger and smaller recipients, those receiving kidneys from older and living donors, and those exposed to a higher graft dose. Among laboratory markers, postoperative platelet count was associated with hemorrhage. Five-year graft survival was lower in children with severe hemorrhage compared with those without (62.5% vs. 91.5%, p < 0.001).

The frequency of severe hemorrhage in children treated with kidney transplantation in our center was higher than reported in the literature. The type of donor and the combination of small recipients and large donors were the main risk factors. The need for a larger abdominal dissection area in small children receiving large grafts, contributing to the risk of bleeding, is a possible explanation for this finding.