Point-of-care ultrasound stratified by the wells score for the diagnosis of proximal deep vein thrombosis: A prospective study

Deep vein thrombosis (DVT) affects 1 in 1,000 people, with complications associated both in under and over diagnosis. Duplex ultrasound is the gold standard but its use in emergency settings is limited. Two-point Point-of-Care ultrasound protocol performed by emergency physicians can foster its diagnosis. However, 6% of cases can be missed and its performance stratified by clinical pre-test probability is unknown. To evaluate the diagnostic performance of an extended compression ultrasound (ECUS) protocol performed by emergency physicians when stratified by Wells score. We conducted a prospective diagnostic accuracy study. Adult patients (≥18 years) with suspected DVT were stratified by Wells score (low, intermediate, high risk) and underwent ECUS by trained emergency physicians or residents. Results were compared to complete duplex ultrasound (CDUS) performed by radiologists within 24 hours. Among 194 patients analyzed (54% female, mean age 61±18 years), the overall prevalence of proximal DVT was 17%. The ECUS protocol demonstrated a global sensitivity of 97% (95% CI: 84.2-99.9), specificity of 94.4% (95% CI: 89.7-97.4), positive predictive value of 78.6% (95% CI: 63.2-89.4), and negative predictive value of 99.3% (95% CI: 96.4-100). In the low-risk group, sensitivity was 100% (95% CI: 29.2-100) with a negative predictive value of 100% (95% CI: 90.7-100). The combined use of Wells score stratification and ECUS can reliably exclude proximal DVT in low and intermediate-risk patients, potentially optimizing emergency department resources and facilitating timely clinical decisions. In low-risk patients, this strategy may yield results comparable to comprehensive Doppler ultrasound.