Here are the references and brief overview of Bret Nelson’s talk at the 2011 ACEM conference in Bangkok, Thailand on July 5.
The Focused Assessment with Sonography in Trauma (FAST) was first described decades ago and hundred of citations exist regarding its use. Although it has become a standard part of the evaluation of the trauma patient, there exists some controversy regarding its use. In 2005 a Cochrane Review was published which concluded:
There is currently insufficient evidence from RCTs [randomized controlled trials] to justify promotion of ultrasound-based clinical pathways in diagnosing patients with suspected blunt abdominal trauma.
Stengel D, Bauwens K, Sehouli J, Rademacher G, Mutze S, Ekkernkamp A, Porzsolt F. Emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma. Cochrane Database of Systematic Reviews 2005, Issue 2. Art. No.: CD004446
The review included four RCTs:
Arrillaga A, Graham R, York JW, Miller RS. Increased efficiency and cost-effectiveness in the evaluation of the blunt abdominal trauma patient with the use of ultrasound. The American Surgeon 1999; 65:31-5.
Boulanger BR, McLellan BA, Brenneman FD, Ochoa J, Kirkpatrick AW. Prospective evidence of the superiority of a sonography-based algorithm in the assessment of blunt abdominal injury. Journal of Trauma 1999; 47:632-7.
Melniker LA, Leibner E, McKenney MG, Lopez P, Briggs WM, Mancuso CA. al. Randomized controlled clinical trial of point-of-care, limited ultrasonography in the emergency department: the First Sonography Outcomes Assessment Program Trial. Academic Emergency Medicine 2006; 48:227-35.
Rose JS, Levitt A, Porter J, Hutson A, Greenholtz J, Nobay F, Hilty W. Does the presence of ultrasound really affect computed tomographic scan use? A prospective randomized controlled trial of ultrasound use in trauma. Journal of Trauma 2001; 51:545-50.
Great debate ensued, including a literal debate between Dr. Melniker (author of study #3 above), Dr. Stengel (author of the Cochrane Review on FAST) and other prominent researchers featured during the opening session at the Second World Congress on Ultrasound in Emergency and Critical Care Medicine in New York in 2006.
Dr. Melniker also published the following rebuttal to the Cochrane Review conclusions:
Melniker LA. The value of focused assessment with sonography in trauma examination for the need for operative intervention in blunt torso trauma: a rebuttal to “emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma (review)”, from the Cochrane Collaboration. Critical Ultrasound Journal. 2009;1:73-84.
Included in the rebuttal was an analysis of FAST literature focusing on cases which required operative intervention. Dr. Melniker found the FAST exam had a false negative rate (ie. patient required operative intervention despite a negative FAST exam) in 5.8% of cases as they were initially published. Upon further review of those false negative cases (and exclusion of inadequate studies, patients who did not go to the OR during at the time of their initial evaluation, etc.) it may be that the actual false negative rate approaches 1.1%.
Thus, it is critically important to define appropriate outcome measures when we evaluate the utility of a diagnostic test. Do we care about the FAST exam’s ability to detect hemoperitoneum? The ability to detect which patients should go to the OR? And to what extent does the clinical picture (ie. mechanism of injury and hemodynamic stability) determine how we proceed? Few would argue that ultrasound has better test characteristics than CT scan; the utility of sonography is non-invasive, repeatable examinations at the point of care.
This type of discussion is incredibly important, and helps clinicians better determine how to employ the appropriate diagnostic tests in their practice. Non-operative management of blunt abdominal injury is becoming more common, and our interpretation of the FAST as well as other diagnostic tests must evolve:
- Knudson et al. Nonoperative management of solid organ injuries. Past, present, and future. Surg Clin North Am. 1999 Dec;79(6):1357-71.
- Velmahos et al. High success with nonoperative management of blunt hepatic trauma: the liver is a sturdy organ. Arch Surg. 2003 May;138(5):475-80; discussion 480-1.
- Velmahos et al. Nonoperative treatment of blunt injury to solid abdominal organs: a prospective study. Arch Surg. 2003 Aug;138(8):844-51.
- Haan et al. Nonoperative management of blunt splenic injury: a 5-year experience. J Trauma. 2005 Mar;58(3):492-8.
- Yanar et al. Nonoperative treatment of multiple intra-abdominal solid organ injury after blunt abdominal trauma. J Trauma. 2008 Apr;64(4):943-8.
Discussions of the utility of trauma ultrasound are valuable because they force us to consider best practices in terms of clinical management of trauma, appropriate use of diagnostic tests, as well as determining appropriate outcomes-based metrics for quality healthcare delivery.
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