Perforation of the terminal ileum induced by blast injury: delayed diagnosis or delayed perforation?

Blast injuries are rare, and although blast-induced perforations of the bowel have been described in the past, the entity of a delayed perforation caused by an evolving injury has not been reported. We report three men injured by the explosion of a terrorist bombing in open air. They suffered primary blast injuries, which resulted in isolated perforations of the terminal ileum. They were operated at different times after the blast event. The resected specimens were examined under light microscopy. One patient was operated immediately, and had three perforations in the terminal ileum. In the other two patients, abdominal complaints appeared only 24 and 48 hours later. These two patients were found to have hematomas in the wall of the terminal ileum, and small perforations therein, with almost no contamination of the peritoneal cavity. On histological examination, there were small perforations with disruption of all intestinal layers. In the vicinity of the perforations, the mucosa was necrotic and disorganized. The submucosa showed edema and vascular thrombi, and at several points mucus was shown dissecting through the muscularis propria, thus creating minute microperforations. Because of the findings in these patients, we suggest a mechanism of evolving damage to the bowel wall and delayed perforation rather than delayed diagnosis, after blast injuries. We suggest that patients exposed to a significant blast should be watched carefully for at least 48 hours.