PROPHYLACTIC VENA-CAVA FILTER INSERTION IN PATIENTS WITH TRAUMATIC SPINAL-CORD INJURY - PRELIMINARY-RESULTS

PULMONARY EMBOLISM (PE) IS a devastating complication in patients with traumatic spinal cord injury (SCI). Prophylactic measures such as venous compression hose or low-dose heparin are only partially protective in reducing the risk of venous thromboembolism and are contraindicated in some patients. Because of extended perturbations in fibrinolytic activity, catecholamine effects on platelet aggregation, increased activity of complement and acute phase reactants, abnormally high factor VIII concentrations, and persistent venous stasis with ongoing endothelial damage, the patient with an SCI remains at prolonged risk for venous thromboembolism. A retrospective 5-year review at the Medical Center Hospital of Vermont revealed seven patients with eight documented PEs (three fatal; 2.7%) in 111 SCI patients (6.3%). Six PEs (75%) occurred after discharge from the acute care facility. Median time to PE after injury was 78 days (range, 9-5993). Although comprising only 4% of all trauma admissions, SCI accounted for 31% of all PEs in the total trauma population (2525 patients). Beginning in July 1991, a new prophylaxis protocol was instituted, which included the percutaneous insertion of vena cava filters under local anesthesia in all SCI patients with paraplegia or quadriplegia. Fifteen patients have undergone the insertion of titanium filters. Impedance plethysmography was performed weekly to detect deep venous thrombosis. No complications were associated with vena cava filter insertion. No patients developed deep venous thrombosis during their acute hospitalization (median, 22 d), and no patients have developed PE after filter insertion. A follow-up deep abdominal Duplex scan of the vena cava was performed, with a 30-day patency of 100% and 1-year patency of 81.8%, by the use of life table analysis. The lower patency rate at 1-year follow-up is felt to represent the trapping of thrombus. We conclude that prophylactic vena cava filters are safe and effective in patients with traumatic SCI.