Routine prophylactic vena cava filter insertion in severely injured trauma patients decreases the incidence of pulmonary embolism.

BACKGROUND: Trauma patients are at increased risk for venous thromboembolism despite routine prophylaxis. A five-year retrospective review of pulmonary embolism at the Medical Center Hospital of Vermont showed that four types of injuries (head injuries, spinal cord injuries, complex pelvic fractures, and hip fractures) accounted for 92 percent of pulmonary emboli in patients on the trauma service. STUDY
DESIGN: Beginning July 1991, all patients who met criteria for a high-risk injury (excluding hip fractures) had prophylactic vena cava filters inserted percutaneously in the radiology suite. Weekly impedance plethysmography was performed for the detection of deep vein thrombosis. Following discharge, abdominal duplex ultrasound was performed at one month, six months, and yearly to check filter position and patency.
RESULTS: To date, a total of 63 patients, or 2 percent of the total trauma population, had prophylactic vena cava filters inserted. There were 19 (30 percent) deep vein thromboses in this population of patients and one patient had a pulmonary embolism (1.5 percent). Overall there was significant (chi-square, p < 0.00072) reduction of pulmonary embolism on the trauma service compared to the historical controls. Follow-up examination with abdominal duplex ultrasound showed a 30-day patency rate of 100 percent and a one- and two-year patency rate of 96.1 +/- 3.8 percent by life-table analysis.
CONCLUSIONS: We concluded that prophylactic vena cava filters are efficacious in decreasing the risk of pulmonary embolism in high-risk trauma patients.