Focused assessment with sonography in trauma (FAST): should its role be reconsidered?

Focused assessment with sonography in trauma (FAST) is a limited ultrasound scan performed in the emergency department to assess patients admitted with blunt abdominal trauma (BAT). It is normally undertaken by emergency physicians in order to identify the presence of free fluid, which may represent haemoperitoneum. This potentially allows prompt referral to further imaging, such as a computed tomography (CT) scan, and/or surgery. FAST has been adopted worldwide, and most major trauma centres now have access to an ultrasound machine. Despite the popularity of FAST, there remains a lack of clarity and evidence around any actual contribution to patient survival. An ability to evaluate the true impact of FAST is complicated by factors such as the operator dependence of ultrasound, the improved access, speed and subsequent use of CT (which has reduced the value of FAST in some centres), a lack of standardisation around education and the most effective methods to ensure competence, and variations in the practice, quality and audit of FAST. Enthusiasm for FAST is undiminished among emergency physicians, and in general, point of care ultrasound is escalating in a range of areas, including the emergency department. Small portable and hand held ultrasound machines improve the accessibility of FAST and its benefits are frequently perceived to be an established and essential part of the emergency department service despite its limitations. Since the introduction of FAST, trauma patients are increasingly managed by non-surgical means if haemodynamically stable, and the presence of intraperitoneal fluid does not necessarily influence this decision. Recent developments in multi-detector CT, and in the use of contrast enhanced ultrasound, have broadened the management options for trauma patients, and can support a faster diagnostic pathway than was previously possible. FAST is a limited triage tool, whose actual value in the diagnostic and treatment pathway of patients with BAT remains questionable, and more data are needed to justify its use in the light of these recent developments.