Introduction

Venous thromboembolism (VTE) is a common complication after major trauma, and has a high rate of morbidity and mortality. However, racial disparities in incidence of as well as risk factors for VTE exist between Asian and western populations. The risks for VTE after major trauma in Japanese patients remain unknown. Our objective was to identify risk factors for VTE after severe blunt trauma in Japanese patients.

Methods

We conducted a prospective cohort study to investigate risk factors for VTE in patients who were admitted to our hospital because of blunt trauma between April 2008 and July 2009. We performed VTE screening by duplex ultrasonographic scan for all blunt trauma patients who had bed rest ≥3 days and recorded Injury Severity Score (ISS) ≥9 within the first 7 days after admission. We initiated pharmacologic VTE prophylaxis, first with low-dose unfractionated heparin and then with lowdose warfarin. The chi-square test was used for categorical variables and the t test for continuous variables.

Results

A total of 101 patients (69 males, 32 females) with blunt trauma (median age 48.48 ± 20.5 (SD) years and mean ISS of 20.0 ± 10.2) were enrolled in this study. Pharmacologic VTE prophylaxis was initiated in 61 of these patients (60.4%). Ten patients (10.0%) experienced VTE. Univariate analysis of potential factors for VTE identified significant associations between thrombosis and the following factors: transfusion, major surgery, the presence of a central venous line in the femoral vein, and direct traction of lower limb (P < 0.05 for all these factors).

Conclusions

The incidence of VTE in Japanese patients with severe blunt trauma was 10.0%. These risk factors have all been given in the results above.