Comparison of changes in intestinal length and circumference after 90 per cent bypass and 90 per cent resection.

Compensatory hypertrophy was compared in rats that had undergone 90 per cent small intestinal resection and rats that had undergone 90 per cent small intestinal bypass. Increases in intestinal length and circumference occurred rapidly in both groups and were virtually identical. Lengthening was more pronounced in the jejunum; increase in circumference was greater in the ileum. Increases in length and circumference of the appendix were seen in both experimental groups. These studies suggest that compensatory hypertrophy can occur in patients after either intestinal bypass or resection, and that patients with bypasses have a less difficult postoperative course because of their preexisting obesity.