Serial FAST scans reveal delayed mesenteric injury in a polytrauma patient: A case report.

Background: Focused Assessment with Sonography for Trauma (FAST) is a cornerstone in the early assessment of trauma patients. However, a negative initial FAST does not always rule out intra-abdominal injury. Case presentation: A middle-aged male presented to the ED following a motor vehicle collision. Both FAST and CT scans were initially negative for significant intra-abdominal injury. He was clinically stable and prepared for transfer to a trauma center. Repeat assessment due to subtle hypotension revealed free fluid on a repeat FAST. Emergent laparotomy identified a mesenteric tear with ischemic bowel, requiring resection. Conclusion: This case illustrates the diagnostic limitations of a single FAST scan. Serial FAST examinations can reveal evolving injuries and should be considered in trauma protocols, especially in patients with changing clinical status.