Fibrinogen concentration and use of fibrinogen supplementation with cryoprecipitate in patients with critical bleeding receiving massive transfusion: a bi-national cohort study.

We aimed to compare hypofibrinogenaemia prevalence in major bleeding patients across all clinical contexts, fibrinogen supplementation practice, and explore the relationship between fibrinogen concentrations and mortality. This cohort study included all adult patients from 20 hospitals across Australia and New Zealand who received massive transfusion between April 2011 and October 2015. Of 3566 patients, 2829 (79%) had fibrinogen concentration recorded, with a median first and lowest concentration of 2·0 g/l (interquartile range [IQR] 1·5-2·7) and 1·8 g/l (IQR 1·3-2·4), respectively. Liver transplant (1·7 g/l, IQR 1·2-2·1), trauma (1·8, IQR 1·3-2·5) and vascular surgery (1·9 g/l, IQR 1·4-2·5) had lower concentrations. Total median fibrinogen dose administered from all products was 7·3 g (IQR 3·3-13·0). Overall, 1732 (61%) received cryoprecipitate and 9 (<1%) fibrinogen concentrate. Time to cryoprecipitate issue in those with initial fibrinogen concentration <1 g/l was 2·5 h (IQR 1·2-4·3 h). After adjustment, initial fibrinogen concentration had a U-shaped association with in-hospital mortality [adjusted odds ratios: fibrinogen <1 g/l, 2·31 (95% confidence interval (CI) 1·48-3·60); 1-1·9 g/l, 1·29 (95% CI 0·99-1·67) and >4 g/l, 2·03 (95% CI 1·35-3·04), 2-4 g/l reference category]. The findings indicate areas for practice improvement including timely administration of cryoprecipitate, which is the most common source of concentrated fibrinogen in Australia and New Zealand.