Aetiology and outcome of massive transfusion in two large London teaching hospitals over a 3-year period (2012-2014)

Abstract

Objectives: The objectives of this study were to determine: (i) the incidence of massive transfusion (MT) (defined as transfusion of ≥5 red-blood-cell (RBC) units within 4 h, and/or ≥10 RBC units within 24 h of bleeding) over a 3-year period; (ii) the cause, and mortality rate of patients who received MT (from any cause); and (iii) the risk factors for death.

Background: MT can occur in different clinical settings, yet little is known about its epidemiology/clinical outcomes.

Methods: Data was extracted using transfusion laboratory information management system (LIMS) and patients' electronic databases.

Results: We identified 701 episodes (incidence 1.7 per 1000 admissions [95% confidence interval (CI): 1.6-1.9], belonging to 678 patients (225 females and 453 males, median age 61). Main causes of MT were cardiac surgery (35%), trauma (28%), medical (10%) and vascular surgery (9%). The overall mortality was 32%, and the median number of days spent in hospital was 14 and 2 for those who survived and those who died, respectively. Multivariable analysis showed that cardiac surgery was associated with 56% (95% CI: 9-78%) lower odds of death compared to other surgery, and transfusion of 10-14 RBC and >15 RBC units (compared with 5-9 RBC units) were associated with 2.1 (95% CI: 1.4-3.3) and 9.9 (95% CI: 4.6-21.1) times higher odds of dying, respectively.

Conclusion: In-hospital morbidity and mortality of MT is high. Future research should focus on unifying the definition of MT, and early identification of the MT markers in order to improve outcomes.

Keywords: causes; clinical outcomes; massive transfusion; transfusion management.