Objective: To assess the short- and long-term outcomes of vena cava filter (VCF) placement for prophylaxis against pulmonary embolism in patients at high risk due to trauma.
Design and setting: Case series at a level I trauma center.
Patients: Patients were considered for prophylactic VCF placement if they met 1 of the injury criteria--spinal cord injuries with neurologic deficit, severe fractures of the pelvis or long bone (or both), and severe head injury--and had a contraindication to anticoagulation.
Intervention: Vena cava filters were placed percutaneously by the interventional radiologists when the acute trauma condition was stabilized following admission.
Main outcome measures: Filter tilt of 14 degrees or more, strut malposition, insertion-related deep vein thrombosis, pulmonary embolism, or inferior vena cava patency.
Results: There were 132 prophylactic VCFs placed. A 3.1% rate of insertion-related deep vein thrombosis occurred, all of which were asymptomatic. Filter tilt occurred in 5.5% of patients and strut malposition in 38%. Three cases of pulmonary embolism (1 fatal) occurred in a prophylactic VCF, and all patients had either filter tilt or strut malposition. The risk of pulmonary embolism developing was higher in those patients with filter tilt or strut malposition than in those who did not have these complications (6.3% vs 0%; P=.05; Fisher exact test). The 1-, 2-, and 3-year inferior vena cava patency rates (+/-SD) were 97%+/-3%.
Conclusions: Prophylactic VCF can be placed safely with an acceptable rate of insertion-related deep vein thrombosis and long-term inferior vena cava patency. Patients with prophylactic VCF remain at risk for pulmonary embolism if the filter is tilted 14 degrees or more or has strut malposition. In such patients, consideration should be given to placing a second filter.