Objectives Although fixed dose regimens using four-factor prothrombin complex concentrate (4F-PCC) are more widely accepted, using a ‘one size fits all’ approach remains an area of uncertainty. The primary objective of this study was to compare percentages of haemostasis between fixed dose and weight-based dose 4F-PCC regimens for multiple bleed types and anticoagulants. Secondary objectives compared differences in the time to administration and in-hospital mortality.

Methods This retrospective, cohort study took place at a community hospital and included patients ≥18 years of age receiving 4F-PCC for major bleeding while on either warfarin or a factor-Xa inhibitor between January 2015 and December 2022. Patients received either fixed dose (treatment) or weight-based dose (comparison). Patients who had been treated for a non-urgent procedure, with unknown haemorrhage source, not on anticoagulation, coagulopathic from hepatic failure, had received dabigatran or were allergic to heparin were excluded. Fisher’s exact test and logistic regression were used to analyse primary and secondary outcomes.

Results 94 patients met the inclusion criteria; 38 patients were assigned to the treatment group and 56 to the comparator group. There was no statistical evidence of a difference in the achievement of haemostasis between groups (45% vs 46%, p=0.872). The fixed dose patients received the dose on average 13 min faster than weight-based (32 min vs 46 min, p=0.031). There was no difference in mortality (29% vs 29%, p=0.968).

Conclusion Fixed 4F-PCC regimens may achieve similar outcomes and a faster time to administration compared with weight-based regimens.