Effect of terminal ileal transposition on intestinal absorption following proctocolectomy

Comparing reconstruction with ileocecal graft to jejunal interposition pouch after total gastrectomy in rats

After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation.

Ileal transposition provides insight into the effectiveness of gastric bypass surgery

Despite dramatically increased research efforts to discover cures for the rising health issue of obesity, bariatric (obesity) surgery remains the most effective treatment. Obese people and especially those classified as morbidly obese often suffer from associated co-morbid conditions such as type-II diabetes. In most cases, bariatric surgery results in rapid and sustained decreases in excess body weight. Recent reports have identified significant improvements in glucose homeostasis after surgery that are coincident and often precedent to any measurable weight loss. These studies suggest an inhibition or enhancement of a "factor" within the intestinal tract that improves glycemia independent of body fat stores. These observations have sparked renewed investigation into the mechanisms underlying successful obesity surgeries such as gastric bypass. It is becoming increasingly clear that restriction and malabsorption are not the only two mechanisms important for inducing long-term weight loss or the improvements in diabetes. Investigating the hypothesis that the distal intestine (ileum) holds additional answers into a third mechanism, I used the model of ileal transposition to help identify endocrine changes in the gut following obesity surgery. This review will explore the model of ileal transposition and speculate on its usefulness as a tool to dissect out additional mechanisms underlying effective obesity surgeries. Also discussed will be the ileal-produced hormone glucagon-like peptide and its role in mediating the improvements in diabetes and weight loss after bariatric surgery.

The jejunal pouch as a rectal substitute after proctocolectomy

Our hypothesis was that a jejunal pouch used as a rectal substitute after proctocolectomy would slow enteric transit, delay defecation, and decrease stool frequency compared to an ileal pouch so used. Twelve dogs underwent proctocolectomy; six had a jejunal pouch-distal rectal anastomosis and six had an ileal pouch-distal rectal anastomosis. After recovery, postprandial mouth-to-anus transit was slower in jejunal pouch dogs (253 +/- 18 minutes [mean +/- SEM]) than in ileal pouch dogs (112 +/- 7.9 minutes; P <0.05). Moreover, jejunal pouch dogs passed only 4.1 +/- 0.3 stools during the 12 hours after eating, whereas ileal pouch dogs passed 6.3 +/- 0. 9 stools (P <0.05). The mean frequency of proximal ileal pacesetter potentials after feeding was less in jejunal pouch dogs (12 +/- 0.4 cycles/min) than in ileal pouch dogs (16 +/- 0.3 counts/min; P = 0. 01), and jejunal pouches had more action potentials (jejunal = 82% +/- 4.3% of pacesetter potentials had action potentials, ileal = 61% +/- 3.0%; P <0.05). In contrast, gastric emptying and pouch motility, emptying, mucosal integrity, and bacteriologic and histologic properties were similar in the two groups of dogs. We concluded that the jejunal pouch operation slowed enteric transit, delayed defecation, and decreased postprandial stooling compared to the ileal pouch operation.

Bowel dysfunction after bladder reconstruction

PURPOSE

Bowel function may be disturbed after intestinal segments are used in urinary reconstruction. The etiology of this condition and its incidence in different patient groups is unclear. We studied the incidence of bowel disturbance in patients who underwent bladder replacement, continent diversion, enterocystoplasty for idiopathic detrusor instability and ileal conduit diversion.

MATERIALS AND METHODS

We evaluated 71 patients after ileal conduit diversion and 82 after bladder reconstruction, including clam enterocystoplasty for detrusor instability in 28, neurogenic bladder dysfunction in 26 and nonneuropathic conditions in 28. We noted the severity of symptoms, such as frequency of defecation, nocturnal diarrhea, flatus leakage, fecal urgency, fecal incontinence and explosive diarrhea, as well as quality of life.

RESULTS

Of the patients who underwent bladder reconstruction 24% had symptoms of bowel dysfunction preoperatively and 42% of those who were asymptomatic preoperatively described new bowel symptoms postoperatively. These symptoms were most common and severe in 54% of patients after clam enterocystoplasty for detrusor instability compared to 26% with neuropathy, 14% with a nonneuropathic condition and 15% with an ileal conduit. Compared to those in other groups patients who underwent enterocystoplasty for detrusor instability had a significantly higher incidence of nocturnal bowel movements (18 versus less than 4%, p <0.01), flatus leakage (29 versus less than 8%, p <0.01), fecal urgency (39 versus less than 12%, p <0.001) and fecal incontinence (32 versus less than 16%, p <0.001). The length of ileum used for clam enterocystoplasty was only slightly greater than that used for ileal conduit operations (25 versus 18 cm.). Of the patients who underwent enterocystoplasty for detrusor instability 29% regretted undergoing the procedure due to subsequent bowel symptoms.

CONCLUSIONS

After enterocystoplasty for detrusor instability patients are at risk of significant bowel symptoms. The development of new bowel symptoms was associated with poor patient satisfaction.