Hypothesis Insertion of inferior vena cava filters (IVCFs) can prophylactically reduce pulmonary embolism (PE) in trauma patients.
Design Retrospective review.
Setting Urban, level I trauma center.
Patients Two hundred blunt trauma patients undergoing IVCF placement.
Interventions In 122 patients who had already been diagnosed as having deep vein thrombosis (DVT) (112 patients) and/or PE (22 patients), the insertion of the IVCF was considered "therapeutic." In 78 patients who had no evidence of DVT or PE but who were considered to be at high risk for a PE, the IVCF was considered "prophylactic."
Main Outcome Measures Incidence of PE and related mortality and morbidity in therapeutic vs prophylactic IVCFs.
Results The number of prophylactic IVCFs inserted increased significantly from only 4% (3/68 cases) from 1991 through 1996, up to 57% (75/132 cases) from 1997 to June 2001. Although the mean ± SD age (51 ± 20 years vs 41 ± 15 years; P<.001) was higher in the therapeutic group, there was no difference in the mean ± SD Injury Severity Scores (20 ± 12 vs 21 ± 11). Therapeutic filters were placed much later after injury (mean ± SD time, 11 ± 7 vs 3 ± 2 days; P<.001). The mortality rate was 11% (13/122 patients) in patients having a therapeutic IVCF, as compared with only 3% (2/78 patients) in those placed prophylactically (P = .07). None of the patients who had placement of a prophylactic IVCF developed subsequent PE. The incidence of PE decreased in all blunt trauma patients from 0.29% before 1997 to 0.15% after January 1, 1997, when 57% of the IVCF inserted were prophylactic (P = .06).
Conclusions Prophylactic IVCFs should be inserted within 48 hours of injury in specific trauma patients at high risk for PE and with contraindications to anticoagulation.
