Test Characteristics of Emergency Physician-Performed Limited Compression Ultrasound for Lower-Extremity Deep Vein Thrombosis

Background: The current literature suggests that emergency physician (EP)-performed limited compression ultrasound (LCUS) is a rapid and accurate test for deep vein thrombosis (DVT).

Objective: Our primary objective was to determine the sensitivity and specificity of LCUS for the diagnosis of DVT when performed by a large heterogeneous group of EPs.

Methods: This was a prospective diagnostic test assessment of LCUS conducted at two urban academic emergency departments. The scanning protocol involved compression at the common femoral, superficial femoral, and popliteal veins. Patients were eligible if undergoing radiology department ultrasound of the lower extremity with moderate or high pretest probability for DVT, or low pretest probability for DVT with a positive d-dimer. The enrolling EP performed LCUS before radiology department ultrasound of the same lower extremity. Sensitivity, specificity, and associated 95% confidence intervals (CIs) were calculated with the radiologist interpretation of the radiology department ultrasound as the criterion standard.

Results: A total of 56 EPs enrolled 296 patients for LCUS, with a median age of 50 years and 50% female. Fifty (17%) DVTs were identified by radiology department ultrasound, and another five (2%) cases were deemed indeterminate. The sensitivity and specificity of EP-performed LCUS was 86% (95% CI 73-94%) and 93% (95% CI 89-96%), respectively.

Conclusions: A large heterogeneous group of EPs with limited training can perform LCUS with intermediate diagnostic accuracy. Unfortunately, LCUS performed by EPs with limited ultrasound training is not sufficiently sensitive or specific to rule out or diagnose DVT as a single testing modality.