Timing of the occurrence of pulmonary embolism in trauma patients

Objective: To determine how soon after trauma pulmonary embolism (PE) occurs and if there is an association between the duration of this interval and mortality. Design: Retrospective case series. Patient: All patients admitted to our trauma service with established PE based on high probability findings on ventilation perfusion scan, positive results on a pulmonary arteriogram, or autopsy from July 1, 1990, to September 30, 1995. Main Outcome Measure: Time interval between injury and PE. Setting: Level I university trauma center. Results: Of 18 255 trauma patients identified, 63 met our criteria for PE (30 using a pulmonary arteriogram; 26, a ventilation perfusion scan; and 7, autopsy). Four patients (6%) had a documented PE on day 1 following injury. Mortality was not correlated with the interval between injury and PE. Of the 63 patients, 58 (92%) had 1 or more established risk factors for thromboembolism. The ratio of PaO ₂ to fraction of inspired oxygen was the only factor predictive of mortality (P=.02, logistic regression analysis). Conclusions: Pulmonary embolism occurs in the immediate period following injury. Aggressive workup in patients with signs consistent with PE should be instituted promptly. Trauma patients who have at least 1 risk factor for thromboembolism should receive prophylaxis as soon after injury as possible.