Optimal Bowel Diameter Thresholds for Diagnosing Small Bowel Obstruction and Surgical Intervention with Point-of-Care Ultrasound

Optimal Bowel Diameter Thresholds for Diagnosing Small Bowel Obstruction and Surgical Intervention with Point-of-Care Ultrasound

Authors: Hamid Shokoohi, Nour Al Jalbout, Gary D Peksa, Katherine Dickerson Mayes, Brent A Becker, Keith S Boniface, Shadi Lahham, Michael Secko, Miromid Chavoshzadeh, Timothy Jang, Michael Gottlieb

Published in: American Journal of Emergency Medicine, July 15, 2024

Conclusions: The study proposes a revised bowel diameter threshold of 2.75 cm for the POCUS-based diagnosis of SBO, which shows improved diagnostic accuracy over the traditional 2.5 cm threshold. The findings indicate that diagnostic thresholds may need to be adjusted based on patient age and sex to optimize the accuracy of SBO diagnosis in the emergency department.

Methods: A secondary analysis of data from a prior systematic review on POCUS for SBO diagnosis was performed, involving five academic emergency departments. Data included imaging results, surgical findings, and final diagnoses, with a focus on small bowel diameter measurements obtained via POCUS. Receiver operating characteristic curves (ROC AUC) were used to identify the most effective thresholds for diagnosing SBO and predicting the need for surgical intervention, with additional subgroup analyses by sex and age.

Results: Out of 403 patients, 367 were included in the final analysis. The study identified 2.75 cm as the most accurate bowel diameter threshold for predicting SBO, with an AUC of 0.76. A diameter of ≤1.7 cm was associated with 100% sensitivity (no false negatives), and a diameter of ≥4 cm provided 90.7% specificity for SBO. Age and sex influenced the optimal thresholds, suggesting differences in diagnostic accuracy across these subgroups. The study found no significant correlation between bowel diameter and the likelihood of requiring surgical intervention.