Point-of-care biliary ultrasound in the emergency department (BUSED): implications for surgical referral and emergency department wait times

BACKGROUND: Patients with uncomplicated biliary disease frequently present to the emergency department for assessment. To improve bedside clinical decision making, biliary point-of-care ultrasound (POCUS) in the emergency department has emerged as a diagnostic tool. The purpose of this study is to analyze the usefulness of POCUS in predicting the need for surgical intervention in biliary disease. METHODS: A retrospective study of patients visiting the emergency department who received a biliary POCUS from December 1, 2016 to July 15, 2017 was performed. The physician interpretations of the biliary POCUS scans were collected, as well as data from the electronic health records including lab values, the subsequent use of diagnostic imaging, surgical consultation or intervention, and 28 days follow-up for representation or complication. RESULTS: Two hundred and eighty-three patients were identified as having received biliary POCUS. Of the patients referred to general surgery who received biliary POCUS 43% received a cholecystectomy. For the outcome of cholecystectomy, the finding of gallstones on POCUS was 55% sensitive (95% CI 40% to 70%) and 92% specific (95% CI 87% to 95%). A sonographic Murphy’s sign was 16% sensitive (95% CI 7% to 30%) but 95% specific (95% CI 92% to 97%) and, gallbladder wall thickness was 18% sensitive (95% CI 9% to 33%) and 98% specific (95% CI 95% to 99%). Patients who received POCUS but did not proceed to confirmatory radiology department imaging had a shorter length of stay (433 min ± 50 min vs. 309 min ± 30 min, P<0.001). DISCUSSION: Point-of-care biliary ultrasound performed by emergency physicians provides timely access to diagnostic information. Positive findings of gallstones and increased gallbladder wall thickness are highly predictive of the need for surgical intervention, and use of POCUS is associated with shorter ER visits. LEVEL OF EVIDENCE: Retrospective cohort study, level III.