Background: Acute upper gastrointestinal bleeding (UGIB) is a common medical emergency resulting in significant morbidity, mortality and cost of care. Whilst red blood cell (RBC) transfusion may be life-saving in massive UGIB, recent controlled trials suggest that a liberal transfusion practice is associated with increased re-bleeding rates and reduced survival after UGIB. 1 Aim: To determine the association between transfusion and rebleeding, mortality at 30 days and at one year after acute non-variceal UGIB. Methods: A retrospective, cohort study of patients who underwent endoscopy at three Western Australian tertiary hospitals for a suspected acute non-variceal UGIB in the period 2008-2010. A detailed chart review and linkage to hospital morbidity, emergency department, death registration and patient blood management data was performed. Logistic regression models were used to investigate factors associated with odds of an early rebleed. Cox models were used to identify factors associated with mortality outcomes. Results: There were 2,238 individuals with a total of 2,370 UGIB admission records. The median age at presentation for first UGIB was 70 years (range 19 to 99 years) and 63% of the cohort was male. Increasing volumes of early RBC transfusion was associated with increased odds of an early rebleed in a dose response trend but only in patients who presented with an Hb >90g/dl (OR 1.5; 95% CI 1.3-1.8; p=0.001). 30-day mortality was 4.9% (n=109). An increased rate of 30 day mortality was observed with increasing number of units of FFP (HR 2.3; 95% CI 1.1-4.6; p=0.02) and platelets (HR 3.7; 95% CI 1.8-7.7; p=0.001) transfused during the UGIB admission after adjusting for other patient and treatment related covariates. There were a further 200 deaths (9%) that occurred after 30 days but within one year of UGIB admission. Transfusion of greater than five units of FFP during the UGIB admission was associated with increased one year mortality (HR 6.7; 95% CI 3.3-13.4; p=0.001) but only for patients who had an INR 150,000 and after adjusting for other covariates. RBC transfusion was not associated with mortality outcomes. Conclusion: In this large, multicentre study, early RBC transfusion was associated with increased rebleeding in patients who presented with Hb > 90g/dl. FFP transfusion and not RBC transfusion was associated with increased mortality outcomes for patients, particularly those with a normal coagulation profile. Reference: 1. Villanueva et al, NEJM 2013; 368: 11-21.