A Prospective, Multicenter Evaluation of Point-of-care Ultrasound for Small-bowel Obstruction in the Emergency Department.

Jackie Anderson, DO | PGY3

The Article: Becker, B. A., Lahham, S., Gonzales, M. A., Nomura, J. T., Bui, M. K., Truong, T. A., . . . Kehrl, T. (2019). A Prospective, Multicenter Evaluation of Point-of-care Ultrasound for Small-bowel Obstruction in the Emergency Department. Academic Emergency Medicine. doi:10.1111/acem.13713


Study Question

  • How accurate is ER POCUS in identifying SBO as compared to abdominal CT?

Methods/Study Design:

  • Prospective, multicenter, observational study

  • Occurred between July 2014 and May 2017

  • ER POCUS interpreted at bedside by ER physician (attending, fellow, PGY2, PGY3) in real-time; also interpreted retrospectively by an expert reviewer after CT results were available; all reviewers were blinded

  • POCUS performed with curvilinear probe

  • Patients were evaluated for SBO if attending was concerned based on presentation and symptoms; patients who did not receive abdominal CT were excluded

  • Criteria used to diagnose SBO on POCUS: small bowel dilation >= 25mm, abnormal peristalsis

  • Criteria used to support SBO diagnosis on POCUS: transition point, intraperitoneal fluid, bowel wall edema (no specific measurement cutoff was used)

Results:

  • 217 patients with overall SBO prevalence of 42.9%

  • POCUS: sensitivity 88%, specificity 54%

  • Expert review: sensitivity 89%, specificity 82%

  • POCUS: 11 false negative, 57 false positives when compared to CT

Strengths/Limitations:

  • All reviewers were blinded

  • ER POCUS performers had no prior training in SBO evaluations

  • ER POCUS classified as “indeterminate” was determined to be positive for SBO; CT interpretations of “ileus vs. SBO” were determined to be positive for SBO

  • Different machines and performers were used among three hospitals with different patient populations 

Authors’ Conclusion:

  • ER POCUS is moderately sensitive for SBO and less specific

Relevance to EM:

  • Opportunity for initial evaluation vs waiting for PO contrast and CT scan

  • Scanners with specific training performed better