Isolated free fluid on computed tomographic scan in blunt abdominal trauma: a systematic review of incidence and management

BACKGROUND: Abdominal computed tomographic (CT) scan is accepted as the primary diagnostic modality in stable patients with blunt abdominal trauma. A recent survey of 328 trauma surgeons demonstrated marked variation in the management of patients with head injuries and the finding of free intra-abdominal fluid without solid organ injury on CT scan. This study was undertaken to attempt to determine what to do when free fluid without solid organ injury is seen on abdominal CT scan in patients with blunt trauma.

METHODS: Articles concerning the incidence and significance of free intra-abdominal fluid on CT scan of blunt trauma patients without solid organ injury were systematically reviewed. A MEDLINE search was performed using terms such as tomography-x-ray computed, wounds-nonpenetrating, small intestine/injuries, time factors, and abdominal trauma and diagnostic tests. Bibliographies of pertinent articles were reviewed. Appropriate articles were evaluated for quality and data were combined to reach a conclusion.

RESULTS: Meta-analysis could not be performed because no randomized, prospective, controlled trials could be found. Forty-one articles were excluded from the analysis because they looked at only patients with known injuries to intestine, diaphragm, or pancreas and the investigation of the CT scan findings did not include negative scans. Ten articles, which described CT scan results for all patients presenting with blunt abdominal trauma for a defined period of time, formed the basis of this study. Isolated free fluid was seen in 463 (2.8%) of over 16,000 blunt trauma patients scanned. A therapeutic laparotomy was performed in only 122 (27%) of these patients.

CONCLUSION: The isolated finding of free intra-abdominal fluid on CT scan in patients with blunt trauma and no solid organ injury does not warrant laparotomy. Alert patients may be followed with physical examination. Patients with altered mental status should undergo diagnostic peritoneal lavage.