Comparison of antithrombin III products in patients on extracorporeal membrane oxygenation in a children's hospital: a pilot study of recombinant antithrombin III versus human antithrombin III

Introduction: The optimal therapeutic anticoagulation strategy in pediatric extracorporeal membrane oxygenation (ECMO) has not been established. Heparin has been used as the mainstay of therapy, but in an effort to reduce heparin requirements and potential hemorrhagic complications, supplementation with exogenous antithrombin III (ATIII) has become a common practice among many pediatric ECMO centers. There are two agents currently available for use, and there have been no studies comparing the two products. This pilot study comparing recombinant ATIII and human ATIII aims to increase the understanding of the role of ATIII in pediatric ECMO and provide insight into potential differences between the two agents.

Objectives: The primary objective of the study is to determine the difference between recombinant ATIII and human ATIII in terms of the reduction of heparin infusion rates at 4, 8, 12, and 24 hours post ATIII supplementation. 

Study Design: Retrospective cohort study.

Methods: This retrospective chart review conducted at a children’s hospital included all pediatric patients on ECMO that received either recombinant ATIII or human ATIII from January 2014 to September 2015. The chart review entails the comparison of heparin rates, ATIII levels, activated partial thromboplastin time, activated clotting time, antifactor-Xa levels, complications, hospital and intensive care unit length of stay, 30-day mortality, and cost of the two ATIII products. 

Results: Of the 24 medical records screened, 22 patients were included in the study (36.4% female and 63.6% male). One of the excluded patients never received a dose of ATIII and one patient was not receiving ECMO at the time of ATIII administration. A total of 97 doses of ATIII were administered during the study period in which 47.4% were recombinant ATIII and 52.6% were human ATIII.

Conclusions: Final results and analyses expected by the end of April 2016.