Fast-Track Diagnosis: POCUS in SBO for Early Front-Door Referrals from the Ambulance Assessment Bay in today’s crowded ED
Dr Himanshu Gul Mirani, Dr Hind Goriel
Case Presentation:
Small bowel obstruction (SBO) is a common emergency presentation requiring early diagnosis and intervention. Traditionally, CT imaging is the gold standard for confirming SBO, but delays in obtaining CT scans can impact timely management. Point-of-care ultrasound (POCUS) is increasingly recognized for its role in diagnosing SBO, offering real-time bedside assessment. We present a case where POCUS facilitated early diagnosis and expedited surgical referral, even before confirmatory imaging.
An 89-year-old male with a history of open appendectomy over a decade ago, presented with a two-day history of worsening abdominal pain, nausea, and vomiting. His last bowel movement was two days prior. He was hemodynamically stable with mild abdominal distension but no peritonitis. Initial venous blood gas
(VBG) revealed a lactate of 4.2 mmol/L, sodium of 128 mmol/L, and glucose of 9.3 mmol/L.
Given the significant crowding in the emergency department (ED) and an anticipated delay of several hours for CT imaging due to an ongoing backlog, there was a critical need for rapid diagnostic tools to facilitate early clinical decision-making. Recognizing the urgency of the presentation, a POCUS was performed in the rapid assessment bay—an area where ambulance handovers occur and initial triage decisions are made.
Fast-Track Diagnosis: POCUS in SBO for Early Front-Door Referrals from the Ambulance Assessment Bay in today’s crowded ED
Management and Outcome:
POCUS demonstrated dilated small bowel loops, ineffective peristalsis with to-and-fro movement, and interloop free fluid with a "pointy" triangular appearance (Tanga sign). Given these findings, urgent surgical referral was made, and antibiotics were initiated due to the presence of free fluid, raising concern for ischemia. There was no abdominal aortic aneurysm. Subsequent CT confirmed proximal SBO with possible internal herniation but no definitive transition point with some free fluid.
The growing evidence supports POCUS as a valuable tool in SBO diagnosis. A 2024 study by Di Gioia et al. found that POCUS had an 85.7% sensitivity for SBO in the ED, significantly reducing the time to diagnosis and surgical consultation when compared to standard imaging workflows. Another study demonstrated that POCUS could detect SBO with a pooled sensitivity of 88.9%, emphasizing its utility in resource-limited or high-demand settings. While CT remains necessary for identifying transition points and complications, POCUS serves as an efficient, widely available modality that enhances early decision-making.
Integrating POCUS into ED workflows could optimize patient flow by facilitating early referral to surgical assessment units via ED, reducing overall ED length of stay. This case reinforces the role of POCUS in expediting SBO recognition and ensuring timely escalation of care.
Key Learnings and Points:
POCUS enabled early recognition of SBO, prompting timely surgical involvement before CT imaging. The detection of free fluid raised suspicion of advanced disease, emphasizing the role of bedside ultrasound in identifying high-risk patients. This case highlights how integrating POCUS into initial ED assessment can reduce delays in diagnosis and expedite appropriate management.