Emergency ultrasound‐based algorithms for diagnosing blunt abdominal trauma
Abstract
Background
Ultrasonography is regarded as the tool of choice for early diagnostic investigations in patients with suspected blunt abdominal trauma. Although its sensitivity is too low for definite exclusion of abdominal organ injury, proponents of ultrasound argue that ultrasound‐based clinical pathways enhance the speed of primary trauma assessment, reduce the number of computed tomography scans and cut costs.
Objectives
To assess the efficiency and effectiveness of trauma algorithms that include ultrasound examinations in patients with suspected blunt abdominal trauma.
Search methods
We searched the Cochrane Injuries Group's Specialised Register, CENTRAL, MEDLINE, EMBASE, CINAHL, publishers' databases, controlled trials registers and the Internet. Bibliographies of identified articles and conference abstracts were searched for further elligible studies. Trial authors were contacted for further information and individual patient data.The searches were last updated in January 2008.
Selection criteria
Studies: randomised controlled trials (RCTs) and quasi‐randomised trials (qRCTs). Participants: patients with blunt torso, abdominal or multiple trauma undergoing diagnostic investigations for abdominal organ injury. Interventions: diagnostic algorithms comprising emergency ultrasonography (US). Controls: diagnostic algorithms without US ultrasound examinations (for example, primary computed tomography [CT] or diagnostic peritoneal lavage [DPL]). Outcome measures: mortality, use of CT and DPL, cost‐effectiveness, laparotomy and negative laparotomy rates, delayed diagnoses, and quality of life.
Data collection and analysis
Two authors independently selected trials for inclusion, assessed methodological quality and extracted data. Where possible, data were pooled and relative risks (RRs), risk differences (RDs) and weighted mean differences, each with 95% confidence intervals (CIs), were calculated by fixed‐ or random‐effects modelling, as appropriate.
Main results
We identified four studies meeting our inclusion criteria. Overall, trials were of moderate methodological quality. Few trial authors responded to our written inquiries seeking to resolve controversial issues and to obtain individual patient data. We pooled mortality data from three trials involving 1254 patients; relative risk in favour of the US arm was 1.00 (95% CI 0.50 to 2.00). US‐based pathways significantly reduced the number of CT scans (random‐effects RD ‐0.52, 95% CI ‐0.83 to ‐0.21), but the meaning of this result is unclear. Given the low sensitivity of ultrasound, the reduction in CT scans may either translate to a number needed to treat or number needed to harm of two.
Authors' conclusions
There is currently insufficient evidence from RCTs to justify promotion of ultrasound‐based clinical pathways in diagnosing patients with suspected blunt abdominal trauma.
PICOs
Plain language summary
No evidence in favour of using ultrasound to aid diagnosis of patients with a 'blunt' injury to the abdomen
Many people admitted to hospital after an injury have 'blunt' (that is, 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 conclude there is insufficient evidence to justify the use of ultrasound as part of the diagnosis of patients with abdominal injury.
