Effect Of Small Bowel Resection Research Articles

Metabolic and Nutritional Issues after Lower Digestive Tract Surgery: The Important Role of the Dietitian in a Multidisciplinary Setting.

Many patients undergo small bowel and colon surgery for reasons related to malignancy, inflammatory bowel disease (IBD), mesenteric ischemia, and other benign conditions, including post-operative adhesions, hernias, trauma, volvulus, or diverticula. Some patients arrive in the operating theatre severely malnourished due to an underlying disease, while others develop complications (e.g., anastomotic leaks, abscesses, or strictures) that induce a systemic inflammatory response that can increase their energy and protein requirements. Finally, anatomical and functional changes resulting from surgery can affect either nutritional status due to malabsorption or nutritional support (NS) pathways. The dietitian providing NS to these patients needs to understand the pathophysiology underlying these sequelae and collaborate with other professionals, including surgeons, internists, nurses, and pharmacists. The aim of this review is to provide an overview of the nutritional and metabolic consequences of different types of lower gastrointestinal surgery and the role of the dietitian in providing comprehensive patient care. This article reviews the effects of small bowel resection on macronutrient and micronutrient absorption, the effects of colectomies (e.g., ileocolectomy, low anterior resection, abdominoperineal resection, and proctocolectomy) that require special dietary considerations, nutritional considerations specific to ostomized patients, and clinical practice guidelines for caregivers of patients who have undergone a surgery for local and systemic complications of IBD. Finally, we highlight the valuable contribution of the dietitian in the challenging management of short bowel syndrome and intestinal failure.

Partial Small Bowel Resection with Sleeve Gastrectomy Increases Adiponectin Levels and Improves Glucose Homeostasis in Obese Rodents with Type 2 Diabetes

The aim of this study was to examine the effect of small bowel resection with and without sleeve gastrectomy on glucose homeostasis in an obese rodent model of type 2 diabetes. Zucker diabetic fatty rats were randomized into three surgical groups: Sham, small bowel resection, and small bowel resection with sleeve gastrectomy (BRSG). Weight and fasting glucose levels were measured at randomization and monitored after surgery. Oral glucose tolerance testing was performed at baseline and 45days after surgery to assess glucose homeostasis and peptide changes. At baseline, all animals exhibited impaired glucose tolerance and showed no difference in weight or fasting (area under the curve) AUC(glucose). At sacrifice, Sham animals weighed more than BRSG animals (p=0.047). At day 45, the Sham group experienced a significant increase in AUC(glucose) compared to baseline (p=0.02), whereas there was no difference in AUC(glucose) in either surgical group at any time point: BR (p=0.58) and BRSG (p=0.56). Single-factor ANOVA showed a significant difference in AUC(glucose) of p=0.004 between groups postoperatively: Sham (50,745±11,170) versus BR (23,865±432.6) (p=0.01); Sham versus BRSG (28,710±3188.8) (p=0.02). There was no difference in plasma insulin, GLP-1, or adiponectin levels before surgery, although 45days following surgery adiponectin levels where higher in the BRSG group (p=0.004). Partial small bowel resection improved glucose tolerance independent of weight. The combination of small bowel resection and sleeve gastrectomy leads to an increase in adiponectin levels, which may contribute to improved glucose homeostasis.

Short- and long-term effects of small bowel resection: a unique histological study in a piglet model of short bowel syndrome

If we are to develop successful interventions to improve clinical outcomes for short bowel syndrome patients we require (1) knowledge of changes within the epithelial population following small bowel resection (SBR) and (2) an idea of when these changes occur to inform on the timing of potential interventions aimed at enhancing the adaptive response. The aim of this study was to produce a temporal map of epithelial changes within the crypt and villus at early and late adaptation phases. Four-week-old piglets underwent a 75% SBR or sham operation and were studied at 2, 4 and 6 weeks post-operation to allow analysis of early and late adaptation responses. Piglets received polymeric infant formula (PIF). Immunohistochemistry with specific cell markers was used to quantitate intestinal cell types and the total cell numbers. Changes within the crypt were temporally dependent on an early significant increase in enterocytes and proliferative cells not sustained at 6 weeks. Goblet cell numbers were increased at all time points. Despite a significant increase in total villus cell numbers at 6 weeks there was no change in specific cell types. We observed two distinct phases of cellular change following SBR. An early increase in enterocytes and proliferative cells was not reflected in increased weight gain indicating the early increase represents immature enterocytes. Interventions aimed at increasing differentiation of the rapidly changing crypt population would allow for an earlier increase in absorption.

Small bowel resection‐associated urinary calcium loss in rats on long‐term total parenteral nutrition

This study was designed to study the effects of small bowel resection on daily urinary excretion patterns, plasma and bone levels of magnesium, phosphorus and calcium in rats on long-term total parenteral nutrition (TPN). Male Sprague-Dawley rats weighing 300 to 350 g were randomly divided into two groups with six rats in each group. Control consists of rats whose small intestines were transected but anastomosed. Resected rats had 70% of their small intestine removed. After intestinal resection and transection, rats were infused with a balanced TPN solution for 17 days. Resected rats excreted significantly more calcium than transected rats during the first 10 days of TPN infusion. Peak excretion occurred between day 3 and 4 followed by a trend toward a slightly higher than normal level of calcium excretion between days 10 and 17. Urinary losses of phosphorus and magnesium were not influenced by bowel resection. Plasma and tibia calcium, phosphorus and magnesium levels were not altered. The effects of small bowel resection on urinary calcium loss is specific and our data demonstrate the involvement of gut in regulating urinary calcium excretion and suggest that gut may play a significant role in TPN induced metabolic bone disease.

Small bowel disaccharidase activity in the rat as affected by intestinal resection and pectin feeding

This study investigated the effects of small bowel resection (SBR) and a pectin-supplemented elemental diet (ED) on intestinal disaccharidase activity. Rats underwent placement of feeding gastrostomy and swivel apparatus. Control animals were returned to their cages while resected animals underwent an 80% SBR. Postoperatively, animals received either a pectin-free ED or the ED supplemented with 2% pectin. After 2 wk jejunal and ileal mucosal sucrase, maltase, and lactase activities and protein content were determined. Feeding the ED after SBR resulted in significant increases in all three ileal segmental disaccharidase activities but only maltase activity was significantly increased in the jejunum. The pectin-supplemented ED, however, significantly enhanced the adaptation of jejunal and ileal segmental sucrase, maltase, and lactase activity to SBR with the increase in all three jejunal disaccharidase activities being significantly greater than that of the resected animals fed the ED alone.

Effect of small bowel resection on the intestinal surface acid microclimate in the rat.

The effect of extensive (65%) proximal and middle small bowel resection on the intestinal surface acid microclimate (ISAM) of the remaining ileum in the rat was examined and the results were compared to those of sham-operated rats. ISAM pH measurements were performed in vivo using a pH microelectrode; incubation was performed in Krebs-Ringer phosphate buffer (pH 7.40 +/- 0.02). In the resected rats, ISAM pH of 6.03 +/- 0.07 and 7.22 +/- 0.03 were recorded in the proximal and distal part of the remaining ileum, respectively. In the sham-operated rats, ISAM pH of 6.04 +/- 0.07, 6.98 +/- 0.03 and 7.28 +/- 0.02 were recorded in the proximal jejunum and in the proximal and distal part of the corresponding ileal segment. ISAM pH was significantly lower (p less than 0.01) in the proximal part of the remaining ileum of the resected rats as compared to the corresponding part in the sham-operated rats but was similar in distal ileum. In fact, the ISAM pH of the proximal part of the remaining ileum of resected rats was as acidic as that of the jejunum of the sham-operated rats. These results clearly demonstrate that adaptation in the ISAM occurs in the remaining ileum following extensive resection of proximal and middle small intestine.

Research/Practice Reports: Perspectives on Digoxin Absorption from Small Bowel Resections

Digoxin is a commonly prescribed medication for a variety of cardiovascular abnormalities. The therapeutic index of digoxin is considered narrow and drug is absorbed predominantly from the duodenum and upper jejunum. When the small intestine is intact, the absorption can vary; therefore, in the case of a small bowel resection or bypass, this erratic absorption may be accentuated. There is some controversy concerning the effect of small bowel resection or bypass on the absorption of digoxin. Some investigators have shown that small bowel resection or bypass decreases the absorption of oral digoxin, whereas others report no change in absorption. When the study methodologies were evaluated, certain common factors that support each view were found. In most studies reporting malabsorption, a solid dosage form of digoxin was used. Studies reporting no change in absorption investigated a solution dosage form.

The effect of small bowel resection and subsequent precise antrectomy on lower esophageal function in rhesus monkeys

The lower esophageal high pressure zone (HPZ) was characterized manometrically and reflux status determined in eight male rhesus monkeys. The studies were repeated six weeks and six months after 50 per cent distal small bowel resection. At the same time fasting serum gastrin and gastric inhibitory polypeptide values were assayed. In seven animals precise antrectomy with gastroduodenal anastomosis was performed and the studies repeated. HPZ pressure increased from 6.7 ± 0.67 mm Hg (± 1 SEM) to 10.3 ± 0.76 mm Hg at six weeks (p < 0.005). At six months the pressure was 9.3 ± 1.02 mm Hg (p < 0.02) and after antrectomy 15.2 ± 3.1 (not significant from 6 month value, p < 0.02 from control). Serum gastrin and GIP values showed significant elevations at six weeks, but six month and postantrectomy results were not statistically different from control. Reflux episodes for the group were reduced at six weeks and six months. After antrectomy increased reflux was noted.

Effect of Small Bowel Resection on the Gastric Mucosa in the Rat

Male Sprague-Dawley rats (120 to 130 gm), unoperated, sham-operated, and those with a 50% resection of the proximal small intestine, were studied after periods of 3, 6, 9, or 12 months. Differences in body weight and in the surface area, thickness, volume, and cellular content of the gastric mucosa between these three groups of animals were compared and statistically analyzed. After an initial loss in body weight, animals with small bowel resection and sham-operated animals attained weights equivalent to unoperated controls. Comparison of the groups for mucosal surface areas of the body of the stomachs showed no significant differences at the 3-, 6-, or 9-month periods. However, 12 months after surgery, the mucosal surface area of stomachs from resected animals was significantly greater than in corresponding controls. At 3, 6, and 9 months after resection, the thickness and volume of the gastric mucosa and the epithelial cell populations (parietal and nonparietal) of the gastric glands were significantly greater than in controls. However, at 12 months, there was no significant difference in any of these parameters between the controls and the experimental animals. The DNA content of the gastric mucosa was significantly greater for animals with small bowel resection than for corresponding controls at 1 and 6 months after surgery. It is concluded that hyperplasia of the gastric glands exists for at least 9 months after proximal small bowel resection in the rat. This hyperplastic response may be responsible for the previously observed (N Engl J Med 272:509-514, 1965; Surgery 65:292-297, 1969) gastric hypersecretion associated with extensive small bowel resection.

Effect of small bowel resection on gastrin release, catabolism, and activity in dogs

Effects of upper small bowel resection on acid secretion and serum gastrin concentration after infusion of exogenous gastrin or feeding were tested on three dogs with gastric fistula and Heidenhain pouch. These studies indicate that the increased acid response from the Heidenhain pouch to a meal after bowel resection is due to an increased reactivity of the parietal cells and an increase in the stimulation of these cells. These effects could be related to the removal of intestinal inhibitors acting on the parietal and G cells, or to the interruption of inhibitory neural reflexes between the small bowel and the stomach, or both.