Accuracy of bedside ultrasound for the detection of soft tissue foreign bodies by emergency doctors

Objective: To assess the ability of emergency physicians and emergency trainees to detect soft tissue foreign bodies using typical ultrasound equipment. Methods: Following a 20 min interactive training session, emergency physicians and emergency trainees were assessed on ability to identify subcutaneous foreign bodies (wood, glass, plastic, gravel and metal) embedded in an experimental model containing both sham and real entry point incisions. In the second phase of the experiment accuracy of detection of multiple foreign bodies was assessed in a similar sonographic phantom. Results: Six emergency physicians and 14 emergency trainees performed a total of 400 individual sonographic examinations. Emergency physicians correctly identified 29 of 30 foreign bodies and returned sensitivity, specificity, positive predictive value and negative predictive value of 96.7%, 70%, 76.3% and 95.5%, respectively. Trainees correctly identified 60 of 70 foreign bodies and returned sensitivity, specificity, positive predictive value and negative predictive value of 85.7%, 82.9%, 83.3% and 85.3%. Correct identification of the number of foreign bodies present, when multiple, was low (25% physician vs 36% trainee). Conclusion: These data suggest ultrasound in the hands of emergency doctors might be useful as an initial screening tool for detection of soft tissue foreign bodies.