SGEM#373: Going Ultrasound for Small Bowel Obstructions

Date: July 28th, 2022 Reference: Brower et al. Point-of-Care Ultrasound-First for the Evaluation of Small Bowel Obstruction: National Cost Savings, Length of Stay Reduction, and Preventable Radiation Exposure. AEM July 2022 Guest Skeptic: Dr. Kirsty Challen is a Consultant in Emergency Medicine at Lancashire Teaching Hospitals. She is also the creator of all those wonderful Paper in a Pictures. Case: A 63-year-old woman presents to your emergency department (ED) with two-day history of nausea, vomiting and constipation. She tells you that she had appendicitis complicated by perforation and peritonitis ten years ago and you suspect she has adhesional small bowel obstruction. You call your surgical colleague who, predictably, asks you to order a CT. The patient asks if there is an alternative as she had several CTs on her last admission and is worried about her radiation exposure and her co-pay. Background: Somewhere between two and four percent of patients presenting to US EDs with abdominal pain have a small bowel obstruction (SBO) – those who are managed operatively (who are only 20-30%) account for 60,000 hospitalizations and 565,000 inpatient care days per year. We know that clinical examination has poor sensitivity and specificity for diagnosing SBO and that imaging is therefore necessary. CT is generally the first choice of imaging, the “abdominal series” of plain X-rays have been demonstrated to have poor predictive value, but a 2018 meta-analysis found 92.4% sensitivity and 96.6% specificity with ultrasound [1]. A 2020 national UK report into patients treated for bowel obstruction found delays in imaging and diagnosis and recommended CT with IV contrast as the first-line investigation [2]. Somewhat surprisingly, we’ve never covered SBO on the SGEM, although Ped EM Superhero, Dr Anthony Crocco shared his views on the (lack of) utility of abdominal X-rays in paediatric constipation back in 2016 (SGEM Xtra: RANThony#4). CLINICAL QUESTION: DOES USING POINT OF CARE ULTRASOUND FIRST LINE IN SUSPECTED SMALL BOWEL OBSTRUCTION REDUCE COST, LENGTH OF STAY AND RADIATION EXPOSURE? Reference: Brower et al. Point-of-Care Ultrasound-First for the Evaluation of Small Bowel Obstruction: National Cost Savings, Length of Stay Reduction, and Preventable Radiation Exposure. AEM July 2022 Population: Patients with ICD-10 coding “intestinal obstruction” from 2018 National Hospital Ambulatory Medical Care Survey. Intervention: POCUS-first approach Comparison: CT imaging as baseline Outcomes: Primary Outcome: Cost savings Secondary Outcomes: Reduction in ED length of stay, reduction in radiation exposure and preventable cancer Type: Monte Carlo Modelling This is an SGEM HOP episode, so we are pleased to have two of the authors on the show. Dr. Charles Brower is a second-year resident training in Emergency Medicine at the University of Cincinnati. His primary research interest is the intersection between clinical operations and ultrasound to improve patient outcomes in an efficient and cost-effective way. Also joining us is Dr. Andrew Goldsmith. He is the director of Emergency Ultrasound in the Department of Emergency Medicine at Brigham and Women’s Hospital at Harvard Medical School Authors’ Conclusions: “If adopted widely and used consistently, a POCUS-first algorithm for SBO could yield substantial national cost savings by averting advanced imaging, decreasing ED LOS, and reducing unnecessary radiation exposure in patients. Clinical decision tools are needed to better identify which patients would most benefit from CT imaging for SBO in the ED.” Quality Checklist for Cost Analysis Studies: Part 1: Are the recommendations valid? Did the investigators adopt a sufficiently broad viewpoint? Yes Are the results reported separately for patients whose baseline risk differs? No Were costs measured accurately? Yes Did investigators consider the timing of costs & ...