545 - The Diagnostic Accuracy of Point-Of-Care Ultrasound for Small Bowel Obstruction: A Prospective Study
Wednesday, May 13, 2020
3:24 PM – 3:30 PM
Location: Majestic Ballroom: Majestic
Participants should be aware of the following financial/non-financial relationships:
Justin Larson, MD: No financial relationships or conflicts of interest
Matthew Lohse, MD: No disclosure data submitted.
Alexander Bracey, MD: No financial relationships or conflicts of interest
Lindsay Reardon, MD: No disclosure data submitted.
Rafael F. Fernandes: No financial relationships or conflicts of interest
Samer Sabyi, MD: No disclosure data submitted.
Michael Secko, MD: No disclosure data submitted.
Catherine Silberstein: No disclosure data submitted.
Background and Objectives: Small bowel obstruction (SBO) accounts for 12-16% of surgical admissions. Traditionally, the initial diagnostic test of choice to diagnose a SBO was an abdominal x-ray; however, a meta-analysis showed that point-of-care ultrasound (POCUS) to be both highly accurate in diagnosing small bowel obstruction. The primary objective of this study was to determine the sensitivity and specificity of POCUS compared to Computer Tomography (CT) scan and final discharge diagnosis for the identification of small bowel obstruction when performed by emergency medicine physicians (EPs) with different levels of training. Secondary endpoints included time from triage to ultrasound and CT, time to disposition, and inter-rater reliability.
Methods: This was a prospective cohort study using a convenience sample of patients ≥18 years old presenting to a large academic Emergency Department with abdominal pain, vomiting or other symptoms concerning for a SBO. Patients were evaluated with POCUS prior to either performance or reading of the CT scan. Point-of-care was performed by EPs with different levels of training who completed a 15 min didactic module and five supervised POCUS exams for SBO. Small bowel obstruction on POCUS was defined as dilated (>2.5 cm) loops of small bowel with lack of peristalsis. The gold standard for diagnosis of SBO was results of CT reading by a board-certified radiologist.
Results: Overall, 21 patients were enrolled. A total of 12 (57%) were diagnosed as having a SBO. POCUS had a sensitivity of 92% (95% CI 60-99%), and specificity of 78% (95% CI 40-96%), for diagnosing SBO when compared to CT scan. POCUS had a sensitivity of 92% (95% CI 62-99%), and specificity of 88% (95% CI 47-99%), for diagnosing SBO when compared to final discharge diagnosis. Mean time to US from triage was 125 minutes, versus 206 minutes for CT scan, an average difference of 81 minutes (p=0.008). The finding of dilated loops of bowel had 100% inter-rater reliability.
Conclusion: POCUS performed by EP’s with varying degree of training is accurate in diagnosing SBO. Dilated loops of bowel on POCUS have high inter-rater reliability.