CT IN PATIENTS WITH BLUNT ABDOMINAL-TRAUMA - CLINICAL-SIGNIFICANCE OFINTRAPERITONEAL FLUID DETECTED ON A SCAN WITH OTHERWISE NORMAL FINDINGS

OBJECTIVE. The purpose of this study was to determine the clinical sig nificance of intraperitoneal fluid seen on CT scans with otherwise nor mal findings in patients with blunt abdominal trauma. MATERIALS AND ME THODS. We retrospectively analyzed the CT scans of 60 patients with bl unt abdominal trauma who had scans showing normal findings except for the presence of intraperitoneal fluid. The location of the fluid was d etermined (pouch of Douglas, pelvis, paracolic gutters, mesentery, Mor ison's pouch, perihepatic or perisplenic spaces). The amount of fluid in each location was categorized as minimal, moderate, or marked. The total volume of fluid in each patient was estimated as small (+1), int ermediate (+2), or large (+3) on the basis of the sum of the amount of fluid in the individual peritoneal locations. The amount and location of fluid were compared between patients who required exploratory lapa rotomy and those who were managed conservatively. RESULTS. In most pat ients, the total fluid volume was small (44 patients, 73%) as opposed to intermediate (11 patients, 18%) or marked (five patients, 8%). Thir ty-seven patients had fluid in one location, 12 patients had fluid in two locations, and 11 patients had fluid in three or more locations. I ntraperitoneal fluid tended to accumulate in the pouch of Douglas (67% ) and Morison's pouch (33%). Patients requiring laparotomy had a highe r total fluid volume score compared with the patients managed conserva tively (2.2 versus 1.3, p <.002) and had larger amounts of fluid in th e upper abdomen. Laparotomy was required in only one patient (2%) who had a small amount of fluid compared with three patients (27%) with in termediate and two patients (40%) with marked amounts. Mesenteric and/ or bowel injuries were noted in all six patients at laparotomy. One pa tient had a small superficial liver laceration that was not diagnosed with CT. No other injuries to the solid viscera were missed on the sca ns. Two of the four patients with mesenteric fluid seen on the CT scan had mesenteric lacerations found during surgery, and the remaining tw o did well with conservative management. CONCLUSION. Patients with blu nt abdominal trauma who have small amounts of intraperitoneal fluid as the sole abnormality shown by CT may generally be treated conservativ ely. However, patients with even a small quantity of mesenteric fluid may benefit from peritoneal lavage to help exclude bowel or mesenteric injury. Intermediate and large amounts of fluid are less common as th e sole CT abnormality but have a higher likelihood of being associated with bowel or mesenteric injury.