The association of prothrombin complex concentrates with postoperative outcomes in cardiac surgery: an observational substudy of the FIBRES randomized controlled trial.

PURPOSE The mainstay of therapy for coagulation factor deficiency in cardiac surgical patients is frozen plasma (FP); however, prothrombin complex concentrates (PCCs) may offer logistical and safety advantages. As there is limited comparative evidence, we conducted this study to explore the association of comparable PCC or FP doses with transfusion and outcomes. METHODS This was a post hoc analysis of a multicentre randomized trial comparing fibrinogen concentrate with cryoprecipitate (FIBRES trial) in bleeding cardiac surgical patients. This analysis included 415 patients who received only PCC (n = 72; 17%) or only FP (n = 343; 83%) for factor replacement. The main outcomes of interest were red blood cell (RBC) and platelet transfusion within 24 hr of cardiopulmonary bypass. Secondary outcomes included postoperative adverse events. Associations were examined by hierarchical generalized estimating equation models adjusted for demographic and surgical characteristics. RESULTS The median [interquartile range (IQR)] PCC dose was 1,000 [1,000-2,000] units, while the median [IQR] FP dose was 4 [2-6] units. Each unit of FP was independently associated with increased adjusted odds of RBC (1.60; 95% confidence interval [CI], 1.36 to 1.87; P < 0.01) and platelet transfusion (1.40; 95% CI, 1.15 to 1.69; P < 0.01) while each 500 units of PCC was independently associated with reduced adjusted odds of RBC (0.67; 95% CI, 0.50 to 0.90; P < 0.01) and platelet transfusion (0.80; 95% CI, 0.70 to 0.92; P < 0.01). Adverse event rates were comparable. CONCLUSIONS In cardiac surgical patients with post-cardiopulmonary bypass bleeding, PCC use was associated with lower RBC and platelet transfusion than FP use was. Prospective, randomized clinical trials comparing FP with PCC in this setting are warranted.