In previous reports, the ileum flap was considered to have less tolerance to ischemia than the jejunum flap. It contained more bacteria colonies with less blood supply, and should be more vulnerable to the insult of ischemia with rapid autolysis. Therefore, it was advised that ischemia time for ileum flap transfer should be less than 1 hr. However, clinical evidence has provided different findings.
From 1998 to 2004, 64 patients had microvascular transfer of the intestine which included a segment of ileum. The warm ischemia time and the survival of the flap were analyzed, and the complications were recorded.
There was one failure of the flap which had an ischemia time of 56 min. Forty-five patients had an ischemia time between 1 and 2 hr, and one of them developed partial loss of the anterior wall of the ileum segment. The remaining 18 cases had an ischemia time of less than 1 hr, and one of them had partial necrosis. There was no statistically significant difference between these two groups.
Clinically, the ileum flap can tolerate more than 1 hr of ischemia. This could be explained by its lower metabolic rate, although it contains a larger amount of bacteria. However, it is still advised that the microvascular anastomoses be finished within 2 hr.
