Emergency Ultrasound-based Algorithms for Diagnosing Blunt Abdominal Trauma

This week, as part of the Child Health Emergency Medicine Social Media Campaign, we are highlighting a Cochrane summary on emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma. This review was selected for the TREKK Evidence Repository on multiple trauma.

Key Messages:

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Related TREKK Resources:

Cochrane Summary:

Using ultrasound to aid diagnosis of patients with a ‘blunt’ injury to the abdomen

Many people admitted to hospital after an injury have ‘blunt’ (not penetrating) damage to the abdomen. Doctors treating these patients need to know whether the organs within the abdomen have been injured. Ultrasound scans are believed to help diagnose the patient’s condition. In this review, the authors looked for studies that compared death rates in patients with an abdominal injury where ultrasound was used to aid diagnosis with death rates where no ultrasound was used. They also looked for evidence that ultrasound use could reduce the need to carry out other more complex and more expensive diagnostic tests. However, very few trials have been done and the authors concluded that there is insufficient evidence to justify the use of ultrasound as part of the diagnosis of patients with abdominal injury. Given this degree of uncertainty, it is probably justified to ask doctors on duty for a confirmatory computed tomography (CT) scan in patients who have sustained an injury with a high chance of major trauma (that is, head and brain injury, cervical spine fracture, thoraco-abdominal pelvic trauma, and other injuries).

Authors’ Conclusions:

The experimental evidence justifying FAST (Focused Assessment of Sonography for Trauma)-based clinical pathways in diagnosing patients with suspected abdominal or multiple blunt trauma remains poor. Because of strong heterogeneity between the trial results, the quantitative information provided by this review may only be used in an exploratory fashion. It is unlikely that FAST will ever be investigated by means of a confirmatory, large-scale randomised controlled trial (RCT) in the future. Thus, this Cochrane Review may be regarded as a review which provides the best available evidence for clinical practice guidelines and management recommendations. It can only be concluded from the few head-to-head studies that negative ultrasound (US) scans are likely to reduce the incidence of multi-detector computed tomography (MDCT) scans which, given the low sensitivity of FAST (or reliability of negative results), may adversely affect the diagnostic yield of the trauma survey. At best, US has no negative impact on mortality or morbidity. Assuming that major blunt abdominal or multiple trauma is associated with 15% mortality and a CT-based diagnostic work-up is considered the current standard of care, 874, 3495, or 21,838 patients are needed per intervention group to demonstrate non-inferiority of FAST to CT-based algorithms with non-inferiority margins of 5%, 2.5%, and 1%, power of 90%, and a type-I error alpha of 5%.

Check Out the Full Cochrane Systematic Review Below:

Stengel, D., Rademacher, G., Ekkernkamp, A., Gϋthoff, C., Mutze, S. (2015). Emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma. Cochrane Database Syst Rev, 9, CD004446. doi: 10.1002/14651858.CD004446.pub4

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This post is part of a weekly blog series highlighting pediatric emergency medicine (PEM) focused Cochrane summaries and other key resources selected by TREKK.

Published by arrangement with John Wiley & Sons.