Absorption studies after massive small bowel resection and antiperistaltic colon interposition in rhesus monkeys

An experimental model of massive (80%) small bowel resection and antiperistaltic colon interposition in between the remnant jejunum and ileum was created in rhesus monkeys. The gastrointestinal functions were assessed preoperatively and at different periods after the operation. Progressive increase in the transit time and enhanced absorption of D-xylose and vitamin B12 was observed in these animals. The transit time marginally increased till three months postoperatively, and a significant increase was observed later (4-12 months) in the colon autografted monkeys. After three months, the D-xylose absorption in the colon interpositioned animals was nearly equal to that of normal monkeys. There was no significant difference in the vitamin B12 absorption in the normal and operated animals up to three months, but a significant rise was observed in the latter group after this period. The fecal fat excretion was 33-44% initially, and it gradually decreased to near normal values after nine months. The antiperistaltic colon interposition was effective in improving the early postoperative survival in animals after massive small bowel resection and enhanced the bowel absorption considerably.