Impact of stomach and colon injuries on intra-abdominal abscess and the synergistic effect of hemorrhage and associated injury

Background: Colon wounds are recognized to be highly associated with intra-abdominal abscess (IAA) after penetrating trauma, whereas gastric wounds are thought to contribute minimally to abscess because of the bactericidal effect of low pH, This study evaluated the impact of stomach or colon wounds, the contribution of other risk factors, and associated abdominal injuries on IAA. Methods: Patients with penetrating colon or stomach wounds during a 10-year period were reviewed and stratified by age, Injury Severity Score, transfusions, and associated abdominal injuries. Early deaths (<48 hours) from hemorrhage were excluded, Outcomes analyzed were IAA and death. Results: A total of 812 patients were identified. There were 32 late deaths (4%), of which 28% were attributable to IAA and multiple organ failure. IAA rates for isolated stomach or colon wounds were 0 and 4.2%, respectively. The presence of associated injuries increased IAA rates to 7.5 and 8.8%, respectively, Independent predictors of IAA determined by multivariate analysis included age, transfusions, gunshot wounds, and associated injuries to the liver, pancreas, and kidney. Conclusion: Gastric injuries are equivalent to colon wounds in their contribution to IAA, Contamination from either organ without associated injury is minimally associated with IAA, but injury to both appears synergistic, The immunosuppressive effects of age and hemorrhage, in addition to significant associated injury, enhance the development of IAA.