Venous thrombotic, thromboembolic, and mechanical complications after retrievable inferior vena cava filters for major trauma.

BACKGROUND The ideal thromboprophylaxis in patients at risk of bleeding is uncertain. This retrospective cohort study assessed the risk factors for complications after using retrievable inferior vena cava (IVC) filters for primary or secondary thromboembolism prophylaxis in patients after major trauma. METHODS Using data from radiology, trauma and death registries, the incidence of and risk factors for subsequent deep venous thrombosis (DVT), venous thromboembolism (VTE), and mechanical complications related to retrievable IVC filters in patients, admitted between 2007 and 2012, were assessed in a single trauma centre. RESULTS Of the 2940 major trauma patients admitted during the study period, a retrievable IVC filter was used in 223 patients (7.6%). Thirty-six patients (16%) developed DVT or VTE subsequent to placement of IVC filters (median 20 days, interquartile range 9-33), including 27 with lower limb (DVT), 8 upper limb DVT, and 4 pulmonary embolism. A high Injury Severity Score, tibial/fibular fractures, and a delay in initiating pharmacological thromboprophylaxis after insertion of the filters (14 vs 7 days, P=0.001) were significant risk factors. Thirty patients were lost to follow-up (13%) and their filters were not retrieved. Mechanical complications-including filters adherent to the wall of IVC (4.9%), IVC thrombus (4.0%), and displaced or tilted filters (2.2%)-were common when the filters were left in situ for >50 days. CONCLUSIONS A delay in initiating pharmacological thromboprophylaxis or filter removal were associated with an increased risk of subsequent DVT, VTE, and mechanical complications of retrievable IVC filters in patients after major trauma.