Safety and efficacy of early pharmacological thromboprophylaxis in traumatic brain injury: systematic review and meta-analysis.

Patients with traumatic brain injury (TBI) are at an increased risk of developing venous thromboembolic events (VTE). Pharmacological thromboprophylaxis (PTP) is routinely delayed because of concerns of exacerbating intracranial hemorrhage (ICH). The aim of this review is to examine the literature and assimilate suitable data to assess the safety and efficacy of PTP administered within 72 h in TBI patients. We systematically searched the literature for randomized controlled trials or cohort studies reporting on the timing of PTP in TBI. We dichotomized the timing of PTP to early and late at 72 h post-injury. The rates of VTE and ICH progression were our primary endpoints and were pooled using a fixed-effects model. A total of five retrospective cohort studies were included within the review including a total of 1624 patients, of which 713 received early PTP and 911 received late PTP. Within the early and late group there was a total of 43 and 106 VTE respectively, with a risk ratio of 0.52 (0.37, 0.73). Assessing safety, the relative risk of ICH progression in the early compared with the late PTP group was 0.64 (0.35, 1.14). Based on the available literature, we can tentatively conclude that early PTP (<72 h) reduces the risk of VTE without affecting progression of ICH. However, much work is yet to be done to better clarify ICH subtypes at risk of progression and the implementation of evidence-based guidelines backed up with randomized control trial level evidence.