Can emergency physicians perform extended compression ultrasound for the diagnosis of lower extremity deep vein thrombosis

Abstract

Background: Current point-of-care ultrasound protocols in the evaluation of lower extremity deep vein thrombosis (DVT) can miss isolated femoral vein clots. Extended compression ultrasound (ECUS) includes evaluation of the femoral vein from the femoral vein/deep femoral vein bifurcation to the adductor canal. Our objective is to determine if emergency physicians (EPs) can learn ECUS for lower extremity DVT evaluation after a focused training session. Methods: Prospective study at an urban academic center. Participants with varied ultrasound experience received instruction in ECUS prior to evaluation. Two live models with varied levels of difficult sonographic anatomy were intentionally chosen for the evaluation. Each participant scanned both models. Pre- and post-study surveys were completed. Results: A total of 96 ultrasound examinations were performed by 48 participants (11 attendings and 37 residents). Participants' assessment scores averaged 95.8% (95% CI 93.3%-98.3%) on the easier anatomy live model and averaged 92.3% (95% CI 88.4%-96.2%) on the difficult anatomy model. There were no statistically significant differences between attendings and residents. On the model with easier anatomy, all but 1 participant identified and compressed the proximal femoral vein successfully, and all participants identified and compressed the mid and distal femoral vein. With the difficult anatomy, 97.9% (95% CI 93.8%-102%) identified and compressed the proximal femoral vein, whereas 93.8% (95% CI 86.9%-100.6%) identified and compressed the mid femoral vein, and 91.7% (95% CI 83.9%-99.5%) identified and compressed the distal femoral vein. Conclusion: EPs at our institution were able to perform ECUS with good reproducibility after a focused training session.