Experimental evaluation of the effect of intestinal reflux on weight loss after jejunoileal bypass

The effect on weight loss of reflux of intestinal contents into the bypassed segment of jejunoileum after 90 per cent jejunoileal bypass was investigated in Wistar rats. No difference in weight curves was observed in rats undergoing (a) standard (end to side) jejunoileal bypass, (b) an anti-reflux procedure (end to end bypass with anastomosis of the bypassed segment to sigmoid colon), (c) bypass with separation of the bypassed segment from functioning gut and formation of an ileostomy. Faecal energy and lipid excretion was identical after end to side, and end to end jejunoileal bypass, and no different from that in rats with equivalent small bowel resection. Weight loss and malabsorption after jejunoileal bypass are unaffected by reflux of intestinal contents into the excluded gut. These experimental studies suggest that modifications of the standard jejunoileal bypass operation designed to prevent reflux of intestinal contents are unnecessary.