In-flight ultrasound identification of pneumothorax

Abstract

Ultrasound is a standard adjunct to the initial evaluation of injured patients in the emergency department. We sought to evaluate the ability of prehospital, in-flight thoracic ultrasound to identify pneumothorax. Non-physician aeromedical providers were trained to perform and interpret thoracic ultrasound. All adult trauma patients and adult medical patients requiring endotracheal intubation underwent both in-flight and emergency department ultrasound evaluations. Findings were documented independently and reviewed to ensure quality and accuracy. Results were compared to chest X-ray and computed tomography (CT). One hundred forty-nine patients (136 trauma/13 medical) met inclusion criteria. Mean age was 44.4 (18–94) years; 69 % were male. Mean injury severity score was 17.68 (1–75), and mean chest injury score was 2.93 (0–6) in the injured group. Twenty pneumothoraces and one mainstem intubation were identified. Sixteen pneumothoraces were correctly identified in the field. A mainstem intubation was misinterpreted. When compared to chest CT (n = 116), prehospital ultrasound had a sensitivity of 68 % (95 % confidence interval (CI) 46–85 %), a specificity of 96 % (95 % CI 90–98 %), and an overall accuracy of 91 % (95 % CI 85–95 %). In comparison, emergency department (ED) ultrasound had a sensitivity of 84 % (95 % CI 62–94 %), specificity of 98 % (95 % CI 93–99 %), and an accuracy of 96 % (95 % CI 90–98 %). The unique characteristics of the aeromedical environment render the auditory element of a reliable physical exam impractical. Thoracic ultrasonography should be utilized to augment the diagnostic capabilities of prehospital aeromedical providers.