Safety and Efficacy of Recombinant Factor VIIa (NovoSeven) Use during ECMO Support in Patients after Cardiac Surgery

Background: Acute postoperative bleeding in cardiac surgical patients is a major cause of morbidity and mortality. Substitution of coagulatory factors may not always provide optimal hemostasis and off label, use of recombinant FVIIa has been proposed. When on ECMO, extra care must be taken during coagulatory substitution as clotting of the system may cause cardiovascular complications and possible ECMO failure, leading to death. In this paper, we examined the safety and efficacy of rFVIIa during ECMO support in postoperative cardio-surgical patients. Methods: We retrospectively examined all patients receiving rFVIIa postoperatively from December 2005 and January 2020. Clinical characteristics, demographics, bleeding, thrombotic complications, mortality, and rFVIIa administration were analyzed. Results: A total of 74 patients received rFVIIa postoperatively due to uncontrollable bleeding after cardiac surgery on our ICU. Of these patients, 23 patients were on ECMO treatment. Twelve patients received rFVIIa during, but not prior to the initiation of ECMO therapy. Six patients (50%) were male; mean age was 46 years (30-72 years). Eleven patients (91.7%) were on venoarterial ECMO, one patient was on central ECMO (8.3%). Dose of administered rFVIIa was corrected for body weight; mean dosage was 82μg/kg. We saw a significant reduction in need for red packed cells, fresh frozen plasma and thrombocyte transfusion after rFVIIa administration. There was no impact on the functionality of the ECMO system, especially regarding the oxygenator after rFVIIa administration. One patient suffered a stroke due thromboembolism (8.3%). One patient developed late thromboembolism in the leg (8.3%), and two cases of pulmonary embolism (16.7%) were recorded. Overall survival was 25% and there was no significant difference in survival between ECMO and non-ECMO patients. Weaning from ECMO could be achieved successfully in 41.7% of our patients. Conclusion: Recombinant Factor VIIa is an effective agent in reducing blood loss during ongoing ECMO therapy in patients with refractory bleeding. Although no direct relation between rFVIIa application and thromboembolic events could be established, its use should be done with the utmost care and in selected patients. However, rFVIIa therapy did not impact ECMO function in our cohort.