BACKGROUND To investigate the role of Low-dose, Early Fresh frozen plasma Transfusion (LEFT) therapy in preventing peri-operative coagulopathy and improving long-term outcome after severe traumatic brain injury (TBI). METHODS A prospected, single-centre, parallel-group, randomized trial was designed. Patients with severe TBI were eligible. We used a computer-generated randomization list, and closed opaque envelopes to randomly allocate patients to treatment with
FFP (5mL/kg of body weight) as LEFT treatment or normal saline (5mL/kg of body weight) as no LEFT treatment once admitting to operation room. RESULTS Between 1 January 2018 and 31 November 2018, 63 patients were included and randomly allocated to LEFT (n=28) and NO LEFT (n=35) groups. 20 patients in the LEFT group and 32 patients in the NO LEFT group were included in the final interim analysis. The study was terminated early for futility and safety reasons because of the high proportion of patients (7 of 20, 35.0 %) in the LEFT group developing new delayed traumatic intracranial hematoma (DTICH) after surgery as compared with 3 of 32 in the NO LEFT group (9.4 %) (relative risk, 5.205; 95% CI, 1.159 to 23.384; P=0.023). Demographic characteristics and indexes of severity of brain injury were similar at baseline. CONCLUSION Low-dose, early fresh frozen plasma transfusion therapy was associated with higher incidence of DTICH than normal FFP transfusion in patients with severe TBI. A restricted FFP transfusion protocol, in the right clinical setting, may be more appropriate in patients with TBIs. (Current Controlled Trials number, ChiCTR-INR-17013901).