Venous thromboembolism in trauma: A local manifestation of systemic hypercoagulability?

Background: The purpose of this study was to evaluate the relative importance of systemic hypercoagulability, pre-existing and acquired risk factors, and specific injury patterns in the development of venous thromboembolism (VTE) after injury. Methods: Injured patients with an Injury Severity Score ≥ 15 were followed with lower extremity venous duplex ultrasonography, prothrombin fragment 1 + 2, and quantitative D-dimer levels at 1 and 3 days and then weekly until discharge. Results: Among 101 patients with a mean Injury Severity Score of 27.3 ± 10.5 followed for 12.4 ± 8.7 days, 28 (27.7%) developed a lower extremity thrombosis, 2 (1.9%) sustained a pulmonary embolism, and 1 (0.9%) had a symptomatic upper extremity thrombosis. Although admission fragment 1 + 2 and D-dimer levels were elevated in 81.4% and 100% of patients, respectively, mean levels were not significantly different in those with or without VTE. VTE was more common (p < 0.05) among those with obesity, age > 40 years, immobilization for > 3 days, spine fractures, and lower extremity fractures. However, only obesity (p = 0.004) and immobilization > 3 days (p = 0.05) were independent predictors of VTE in a multivariate analysis. Conclusion: Although elevated in seriously injured patients, neither markers of activated coagulation nor specific injury patterns are predictive of VTE. Associations with immobilization and obesity suggest that VTE after injury is a systemic hypercoagulable disorder with local manifestations of thrombosis related to lower extremity stasis.