Long-term follow-up of trauma patients with permanent prophylactic vena cava filters

Background: Although permanent prophylactic Greenfield filters (PPGF) are effective, their use in young trauma patients who may eventually return to active lifestyles is controversial due to concerns about the safety of the devices over a lifetime. This descriptive study was undertaken to provide follow-up on the long-term safety and durability of PPGF. Methods: All patients receiving a PPGF between April 1, 1992 and March 1, 2001 were sought for follow-up. Contacted patients were interviewed regarding known filter-related complications, venous thromboembolic events, and activity levels since the time of discharge from the hospital. Patients were also offered a physical examination focusing on venous thromboembolic sequelae, a plain film of the abdomen (KUB) to assess filter integrity and location, and an ultrasound to assess caval patency. As the original level of filter placement was usually not known, migration was defined as a filter above the first lumbar vertebra (L1). Results: The eligible cohort consisted of 188 patients. Ninety were unable to be located (47.8%), one refused enrollment (0.5%), and 97 patients or next of kin agreed to be interviewed by phone (51.6%) of whom 69 returned for evaluation (36.7%). No filter-related complications were self-reported. KUBs were performed in 68 patients; one filter strut fracture was found (1.5%), whereas no filter migrations above L1 were noted. No instances of caval thrombosis were found in 55 ultrasounds. Two patients suffered interim pulmonary emboli (2.1%), one of which was fatal. Of 15 interim deaths, autopsy or death certificates were available for four patients, nine had their causes of death related by next of kin, and two were unknown. Although 95.4% of nonspinal cord injury patients reported at least some ability to ambulate, only 64.6% could do so ad libitum. Of those patients ambulating without limitation, 28.6% reported a complete inability to run any distance and another 23.8% could run less than one block. Follow-up for patients completing interviews was 105.3 months ± 18.0 months, and for patients undergoing imaging was 104.6 months ± 16.4 months. Interim deaths occurred at 48.2 months ± 26.0 months. Conclusions: PPGF seem to be safe and effective at 105 months of follow-up; most patients report significant limitations in activity level at this same timeframe. PPGF should be the filter of choice for elderly patients in whom this time period can reasonably be expected to cover the patient's remaining life expectancy.