PB0655 - Clinical impact of factor XIII concentrate on hemorrhagic symptoms for pediatric patients with acquired factor XIII deficiency during extracorporeal membrane oxygenation

Background: Bleeding is a major complication in patients on extracorporeal membrane oxygenation (ECMO). Factor XIII (FXIII) deficiency has been reported during ECMO. However, little is known about the therapeutic threshold of FXIII level on ECMO with anticoagulation and the effects of FXIII concentrate in bleeding management.

Aims: Our study aimed to define the therapeutic threshold of FXIII level and evaluate the effect of FXIII concentrate in ECMO.

Methods: Retrospective chart review was performed in pediatric ECMO patients with bleeding symptoms and FXIII deficiency who were treated by intravenous FXIII concentrate administration. The ISTH bleeding definition was used to classify bleeding events as none (0), minor (1), clinically relevant non-major (2), and major (3). FXIII level was measured using HemosIL FXIII antigen assay on ACL TOP 550CTS coagulation analyzer (Werfen). FXIII level and bleeding grade were compared before and after FXIII concentrate administration. Data is presented as mean±SD, repeated measures ANOVA test was used for statistical analysis with significance at p< 0.05 (Excel 2019).

Results: Patients’ demographics are presented in Table. All patients were anticoagulated with bivalirudin and monitored by activated partial thromboplastin time and bivalirudin level assay using diluted thrombin time. Other coagulation tests and thromboelastometry were unremarkable, and acquired von Willebrand syndrome was ruled out by the multimer study. FXIII concentrate was administered at 35±8 units/kg. FXIII level significantly increased from 41.1±5.8% to 71.8±14.9%, p=0.0002 (Figure 1A). All patients improved their bleeding symptoms after FXIII concentrate administration with a significant decrease in ISTH grade from 2.2±0.9 to 0.5±0.7, p=0.0001 (Figure 1B).

Conclusion(s): Bleeding severity improved after administration of FXIII concentrate in ECMO patients who had FXIII level lower than 50%. Monitoring of FXIII levels in patients with unexplained bleeding on ECMO and FXIII substitution if its level is below 50% is a promising approach and requires further evaluation to mitigate bleeding while on ECMO.