Do transferred patients increase the risk of venous thromboembolism in Trauma centers?

Trauma patients often require initial stabilization followed by transfer for ongoing trauma care. Thus, the administration of VTE prophylaxis is often delayed until admission to the receiving hospital. It is unclear if transfer status is a risk factor for VTE. The National Trauma Database v6.2 was used to identify patients admitted to Level I and II trauma centers. Exclusions included patients on anticoagulation, <18 years, known VTE before trauma, or pregnant. Patients transferred were compared with nontransferred patients. Analysis included 736,374 patients with 189,166 (25.69%) transferred patients within 24 hours of injury. Using weighted measures, VTE was identified in 11,619 (1.50%) patients. The VTE rate was significantly higher in the transferred group compared with the nontransferred group (1.73% vs 1.42%, P = 0.002) including deep venous thrombosis (1.39% vs 1.14%, P = 0.004) and pulmonary embolism (0.45% vs 0.39%, P = 0.003). Multivariable analyses adjusting for patient-level risk factors demonstrated that transfer was associated with a higher likelihood of VTE (aOR 1.18; 95% CI: 1.09-1.28, P ≤ 0.001), pulmonary embolism (aOR 1.21; 95% CI: 1.11-1.33, P ≤ 0.001), and deep venous thrombosis (aOR 1.17; 95% CI: 1.07-1.28, P = 0.0004). Transfer status of trauma patients is a risk factor for VTE. Accepting a transferred patient results in an increased VTE risk and may not be reflective of the quality of care at the receiving facility.