A simplified training method for soft tissue foreign body detection using ultrasound in emergency medicine residency program

Abstract

Using ultrasound for detecting soft tissue foreign bodies seems to be the preferred choice with minimum invasion and easy availability at the bedside in emergency departments. In this study, a workshop (1 hour of lecture presentation and 3 hours of interactive hands-on) was designed to evaluate the efficacy of a short course of simple interactive training to improve the ability of emergency medicine residents to detect foreign bodies with ultrasound. Eight pieces of fresh full thickness (10 × 10 × 10 cm) lamb leg muscle were used in this study. Five different types of foreign bodies, including: a piece of glass (5 × 5 × 4 mm), wood (5 × 5 × 4 mm), gravel (5 mm diameter), plastic (5 × 5 × 2 mm) and a nail (25 mm in length) were placed deep inside each lamb leg. An ultrasound machine with a 7.5 MHz linear probe was used in this study. 35 emergency medicine residents (12 PGY1, 11 PGY2 and 12 PGY3) were enrolled in this study. Pretest and post-test results were compared and analyzed. Among all 35 participants in the training session, foreign body detection was significantly improved after the workshop ( p < 0.001). Overall sensitivity and specificity for differentiating the presence and absence of a foreign body with 95% confidence were 60% (75% for PGY3) and 85.7% (91.7% for PGY3), respectively. The overall accuracy increased from 20.2% to 72.8% due to this session. This study supported the possibility of using ultrasound to detect foreign bodies by emergency physicians with a very short training course. This is highly beneficial for overcrowded emergency departments.