Effects of Early Chemoprophylaxis in Traumatic Brain Injury and Risk of Venous Thromboembolism.

BACKGROUND: The optimal timing to initiate venous thromboembolism (VTE) prophylaxis in patients with a traumatic brain injury (TBI) is still unknown. We designed a study to determine the effect that timing of initiation of VTE prophylaxis has on VTE rates in TBI patients. METHODS: Patient records were obtained from 32 level 1 and 2 trauma centers in the Michigan Trauma Quality Improvement Program from 2008 to 2018. Overall, 5589 patients with a TBI were included and split into cohorts based on VTE prophylaxis initiation time. Outcomes included rate of VTE, mortality, and serious in-hospital complications. RESULTS: There were nine patients (1.3%) in the <24 hour group with a VTE as compared to 36 (2.6%) in the 24-48 hour group, 51 (4.1%) in the 48-72 hour group, and 181 (8.1%) in the >72 hour group (P < .001). The adjusted odds of VTE were significantly greater in patients initiated within 48-72 hours (AOR 2.861, 95% CI 1.271-6.439) and >72 hours (AOR 3.963, 95% CI 1.824-8.612) compared to <24 hours. Patients that received VTE prophylaxis within 24 hours had similar rates of serious in-hospital complication as patients initiated within 24-48 hours (AOR .956, 95% CI .637-1.434) and 48-72 hour (AOR 1.132, 95% CI .757-1.692) but less than the >72 hour group (AOR 1.662, 95% CI 1.154-2.393) groups. DISCUSSION: Patients initiated on VTE prophylaxis within 48 hours of presentation had lower incidence of VTE without a significant increase in serious complications.

The Effect of Antiplatelet Agents on Thromboelastography.

BACKGROUND: Thomboelastography (TEG) is a point of care viscoelastic test that provides an assessment of clot formation and kinetics. Antiplatelet agents are commonly used but there is limited literature evaluating their possible effects on overall clot kinetics. We aimed to evaluate the relationship between antiplatelet agents and clot kinetics as defined by TEG. METHODS: This is a retrospective study of adult patients who underwent TEG from February 2018 to July 2020. Patients who received anticoagulants or blood transfusions within 72 hours, had an incomplete TEG, were diagnosed with COVID-19, or had liver failure were excluded. Patients were stratified based on antiplatelet status. RESULTS: Of 1060 patients, 119 were included (50 controls, 69 antiplatelet agents-37 aspirin monotherapy, 26 dual antiplatelet therapy). Between the control and antiplatelet therapy groups, there was no significant difference in clot time, maximal clot strength, or fibrinogen level. When compared to control patients, patients on dual antiplatelets had significantly higher fibrinogen levels (408.1 mg/dL vs 481.5 mg/dL, P = .013) but no significant differences in clot time or maximal clot strength. In our subgroup analysis, patients on dual antiplatelets had increased maximal clot strength (58.8° vs 63°, P = .005) and fibrinogen levels (384.1 mg/dL vs 481.5 mg/dL, P = .005) compared to those on aspirin alone. DISCUSSION: Compared to control patients and those on aspirin alone, patients on dual antiplatelets have increased maximal clot strength and increased fibrinogen levels. These results can help physicians better target product resuscitation in patients who are on antiplatelet agents.