(806) Plasma-Based vs Viscoelastic Assays in Predicting Massive Bleeding During Pediatric Liver Transplant

Introduction: Pediatric liver failure (LF) induces a complex coagulopathy, which leads to both bleeding and clotting complications. Traditional plasma-based coagulation (PBC) assays are limited in their ability to determine the risk of such events. Whole blood-based viscoelastic assays, such as rotational thromboelastometry (ROTEM), are now increasingly preferred to detect coagulopathy in adult LF, but they are not well characterized in pediatric LF. Hence, we sought to compare PBC with ROTEM assays and their respective associations with intraoperative bleeding during pediatric liver transplantation (LT).

Methods: We retrospectively analyzed simultaneous PBC and ROTEM assays pre-LT and compared their associations with intraoperative estimated blood loss (EBL). Massive EBL was defined as greater than 85th percentile of our cohort (22ml/kg). We used the Mann-Whitney U test or Chi-square test to compare the groups. We performed multivariable regression analysis adjusting for age and type of liver failure. Finally, we performed ROC analysis to determine the predictive ability of PBC and ROTEM parameters for massive EBL during LT.

Results: Of 72 children (median age 39 [13-159] months, 43% male, 21% acute LF, 18% acute-on-chronic LF, and 61% chronic LF), 12 (16.7%) had massive EBL during LT. Univariate analysis revealed that younger age, acute-on-chronic LF, high INR, low platelet count, prolonged aPTT, prolonged EXTEM/INTEM CT, and low EXTEM MCF were associated with massive EBL. On multivariable regression analysis, after adjusting for age and type of liver failure, only platelet count was associated with massive EBL (OR 0.974 [0.949-0.999], p=0.038). The area under the curve (AUC) for the combination of three PBC parameters (INR, aPTT, platelet count) was significantly greater than that of three ROTEM parameters (EXTEM CT, INTEM CT, EXTEM MCF) (0.862 vs. 0.760, p=0.029) in predicting massive EBL.

Conclusions: ROTEM assays were not found to be superior to PBC assays in predicting massive EBL during pediatric LT. Further studies are needed to determine the clinical utility of these assays in the management of the coagulopathy associated with pediatric liver disease.