Significance of periteneal fluid as an isolated finding on abdominal computed tomographic scans in pediatric trauma patients

Background: Peritoneal fluid on abdominal computed tomographic (CT) scan in the absence of solid-organ injury suggests a bowel injury. We sought to determine the significance of peritoneal fluid as the sole finding on abdominal CT scans obtained to evaluate injured pediatric patients. Methods: We performed a retrospective review of abdominal CT scans obtained during the initial survey of blunt trauma patients less than 19 years old during a 5- year period (1991-1995). All patients received intravenous and oral contrast agents. All CT scans were read by a staff radiologist. All CT scan results were retrospectively verified by one of the authors. Results: Of the 259 scans, 157 (59%) were read as normal; 76 (31%) demonstrated solid-organ injury or pelvic fracture; 2 (1%) had pneumoperitoneum and 24 (9%) had peritoneal fluid as the only finding. Quantification of the fluid was done using a previously described method. Of the 16 patients with a small amount of fluid, only 2 (12%) required celiotomy. Of the eight patients with a moderate amount of fluid, four (50%) required celiotomy. At celiotomy, the six patients all had small-bowel injuries. No abdominal CT scan demonstrated extravasation of oral contrast. Conclusion: Intra-abdominal fluid as the sole finding on abdominal CT scan does not mandate immediate celiotomy in the bluntly injured pediatric patient. The patient with fluid in more than one location has a 50% chance of bowel injury. We also conclude that extravasated enteral contrast is rarely present to aid in the diagnosis of bowel injury in children.