The prevalence of chronic deep venous thrombosis in trauma: Implications for hospitals and patients

INTRODUCTION Deep venous thrombosis (DVT) is considered a preventable complication in trauma patients. Hospitals risk financial penalties for DVT rates above accepted benchmarks. These penalties do not apply to chronic DVT, which develops before admission. Lower-extremity duplex ultrasound (LEDUS) can detect characteristics of thrombus chronicity, allowing differentiation of chronic from acute DVT. The objective of this study was to determine the prevalence of chronic DVT in hospitalized trauma patients. METHODS We performed a retrospective review of trauma patients admitted to our Level I trauma center between July 1, 2006 and October 31, 2016 who had a DVT on initial screening LEDUS. Our center utilizes screening and surveillance LEDUS for patients admitted more than 48 hours. Definitions for chronic and acute DVT were extracted from existing literature. Patients with DVT on initial LEDUS underwent review of that LEDUS to assess clot chronicity and were classified as having acute DVT, chronic DVT, or DVT of indeterminate age. Demographic data, medical history, and injury characteristics were collected. Patients with acute DVT and those with chronic DVT were compared. RESULTS The prevalence of chronic DVT among patients with a DVT on initial LEDUS was 29.9%. Chronic DVT occurred in patients who were older and less severely injured. An above-knee component was significantly more common in chronic DVT (65%). Only 34 (41%) of those with chronic DVT reported a history of DVT. Among the patients with chronic DVT, 44 (53%) had a subsequent LEDUS, of whom 4 (9%) showed thrombus progression and 6 (14%) formed a new DVT. CONCLUSION Lower-extremity duplex ultrasound can identify chronic DVT, which represents nearly 30% of all DVT found on initial screening LEDUS in trauma patients. Those with chronic DVT should receive pharmacologic and mechanical prophylaxis because of the incidence of progression and new acute DVT. They should also be counseled regarding the possibilities of recurrence and chronic venous insufficiency. LEVEL OF EVIDENCE Diagnostic study, level III.