Blood transfusion requirements and independent predictors of increased transfusion requirements among adult patients on extracorporeal membrane oxygenation -- a single centre experience.

BACKGROUND/
OBJECTIVES: More adults undergo extracorporeal membrane oxygenation (ECMO) now. They have high transfusion requirements. This study described transfusion requirements of adults during ECMO in a single institution, and determined factors associated with high transfusion requirements. MATERIALS/
METHODS: Retrospective analysis was done on the amount of blood products received by adults during ECMO. Predictors of increased average daily transfusion requirements during ECMO and increased ECMO duration (which correlated positively with total transfusion requirements) were determined.
RESULTS: Forty-one patients (median age 50 years) underwent 42 ECMO sessions for respiratory failure (16.7%), cardiogenic shock (76.2%) or massive pulmonary embolism (7.1%). They received 569 red blood cells, 852 platelets, 126 fresh-frozen plasma (FFP) and 220 cryoprecipitate in total during median ECMO duration of 5 (1-15) days. On multivariate analysis, average daily red blood cell transfusion increased with nadir haemoglobin (Hb) during ECMO (Hb(nadir)) of < 7.5 g/dl (P < 0.001). Average daily platelet transfusion increased with recent antiplatelet agents (P = 0.015) and maximum Hb decline of > 5.5 g/dl during ECMO (P = 0.011). Average daily platelet transfusion > 3 units was also associated with increased ECMO duration (P = 0.024). Average daily FFP transfusion was increased in patients with hypertension (P = 0.007) and Hb(nadir) < 7.5 g/dl (P = 0.050). Patients with sepsis (P = 0.009) or without surgery (P = 0.009) had increased ECMO duration, which correlated positively with total transfusion requirements during the entire ECMO session. ECMO improved mortality of patients with fulminant myocarditis, respiratory failure and massive pulmonary embolism.
CONCLUSION: Adult ECMO patients with lower Hb(nadir) require more daily red blood cell and FFP. Hypertension increases daily FFP requirements. Recent antiplatelet agents, larger Hb decline and longer ECMO duration increase daily platelet requirements. Patients with sepsis or on ECMO for medical reasons have longer ECMO duration, which is associated with total transfusion requirements. Some of these factors may be identified early to optimize blood product support.