Heparin versus bivalirudin anticoagulation management for extracorporeal membrane oxygenation in covid-19: 1-year institutional review

ABSTRACT

Introduction: Anticoagulation strategies for extracorporeal membrane oxygenation(ECMO) support in COVID-19 patients remains controversial. This study aims to present our experience with anticoagulation management and monitoring strategies including bleeding complications during ECMO support. Methods: Retrospectively, we reviewed charts of twelve patients supported with ECMO for COVID-19 from March 2020 to June 2021. Of these, eight patients with veno-venous(VV) ECMO received intravenous(IV) heparin anticoagulation and four with veno-arterial-venous(VAV) ECMO received IV Bivalirudin. Therapeutic partial thromboplastin time(PTT) goal was 50-70seconds in both groups. Results: Average age was 52 years with nine males. All patients had elevated D-dimer level before and during ECMO support. Mean time on ECMO support was 800.3 hours. Overall, therapeutic PTT was achieved in 38% with significant outcomes in Bivalirudin when compared to Heparin group [Heparin33%(24-49%);Bivalirudin51%(24-92%), P<0.00001]. Number of patients remained sub-therapeutic (PTT<50s) was 60% [Heparin63%;Bivalirudin48.2%], and supra-therapeutic (PTT>70s) was 2% [Heparin3%;Bivalirudin0.9%]. In heparin group, major bleeding complications included cerebral in 4, oropharyngeal in 2, and psoas hematoma in 2 patients. Whereas, in Bivalirudin group, only one patient experienced postoperative anemia from acute blood loss. Overall, six died in hospital [Heparin5patients;Bivalirudin1patient];two discharged to another hospital for lung transplant [Heparin0patient;Bivalirudin2patients, 1 died before listing];three discharged to home alive [Heparin3patients;Bivalirudin0patient], and one still remains in the hospital [Heparin0patient;Bivalirudin1patient]. Conclusion: Although results are promising for Bivalirudin in terms of lesser hemorrhagic complications and reduced mortality, smaller sample size may have attenuated the findings. Future studies are warranted.