Long-term follow-up of prophylactic greenfield filters in multisystem trauma patients.

Abstract

The efficacy of prophylactic Greenfield filter (PGF) placement in multisystem trauma patients at high risk for venous thromboembolism has been established. The objective of this study is to demonstrate the long-term safety and durability of PGFs placed in young, active trauma patients. Starting January 1992, all trauma patients at high risk for development of venous thromboembolism were identified for placement of PGFs. These included patients with ISS > 9 and severe closed head injury, spinal injury, pelvic fracture, multiple long bone fracture, or direct iliofemoral venous injury. Four patients with PGFs placed before the study protocol in 1992 were also included. Follow-up was attempted in all patients with at least 5 years' duration since placement of PGF using physical examination, duplex ultrasound (US), and plain abdominal radiograph. There were 108 patients who had a PGF placement during the period of January 1992 to June 1994 that were eligible for the study. Eighteen of these 108 (17%) patients died. Twelve of them (67%) had autopsies and medical records available to determine the cause of death, none from a pulmonary embolism. The average time of death was 2.7 months after injury. The remaining 90 patients and the 4 patients with PGFs placed before 1992 were sought for follow-up, but only 36 patients could be contacted, 33 of which returned for evaluation (35%). The mean time of follow-up from the time of injury to the time of examination was 67.7 months, and the mean age at follow-up was 38.1 years. Although six patients had mild to moderate lower extremity edema on physical examination, none of them had a deep venous thrombosis by US. Radiographs obtained in 19 of the 33 patients showed no migration or breakdown of the Greenfield filters in place. Prophylactic Greenfield filters in high-risk trauma patients are safe and durable. There appears to be no significant consequence in over 5 years of follow-up.