Rapid Proficiency in Femoral and Popliteal Nerve Identification Is Achievable After a Brief Educational Intervention

Introduction Ultrasound guidance for the delivery of regional anesthesia in the emergency department (ED) is an area of increasing interest. However, in order to perform a regional nerve block, one must first be able to correctly identify the specific nerve on ultrasound. Therefore, the primary purpose of this study is to investigate the number of supervised ultrasound examinations required for an emergency medicine (ED) physician to gain proficiency in accurately identifying the nerves of the lower extremity at the level of the femoral and popliteal nerves. Methods The proficiency outcome was defined as the number of attempts a resident needed to locate and correctly identify the femoral and popliteal nerves for 10 consecutive examinations. Didactic education was provided via a one-hour lecture and two supervised hands-on ultrasound examinations for each region prior to testing. Count data are summarized using percentages or medians and ranges. Random effects negative binomial regression was used for modeling panel count data, with the results summarized as an incidence rate ratio (95% confidence interval) and P-values <0.05 considered statistically significant. Results Complete data for the number of attempts, confidence, gender, and years in practice was available for 31 residents. The median number of attempts and range for popliteal and femoral nerves were 0 (0-11) and 0 (0-11), respectively. The median level of confidence and range for popliteal and femoral nerves were 3.5 (1-5) and 3 (1-5), respectively. There was a significant association between confidence and proficiency (P=0.009) and between years in practice and proficiency (P=0.010). Conclusion The findings of this small data set would suggest that proficiency can be quickly obtained in identifying the femoral and popliteal nerves with ultrasound after only a few proctored examinations. A significant association was found between years in practice and proficiency. This suggests that physicians with previous ultrasound scanning experience may require fewer supervised examinations when learning how to identify the femoral and popliteal nerves.