The effect of somatostatin on experimental intestinal obstruction

Gastrointestinal Diseases of Rabbits

Gastrointestinal stasis syndrome is a very common presentation of an ill rabbit to the veterinarian. The causes involved in this syndrome are often multifactorial, and an inappropriate diet puts the rabbit at a greater risk of developing this syndrome. Complications of this disorder can lead to gastrointestinal obstruction, a life-threatening condition that necessitates aggressive medical and in some case surgical therapy. Rabbits may also be presented with signs of diarrhea. However, abnormal cecotrophs must be differentiated from true intestinal diarrhea. The common causes, diagnosis and management of diarrhea including dysbiosis and enteritis are discussed. Other important causes of gastrointestinal disease are infectious disease and liver lobe torsion. Rabbit hemorrhagic disease virus has a new variant that has been identified in mainland Europe, the United Kingdom, and Australia. Subclinical infection of intestinal coccidiosis is a common cause of weight loss in adult rabbits. Liver lobe torsion is a challenging condition to diagnose in rabbits; this chapter discusses the presenting signs, diagnostic techniques, and therapeutic options.

The Role of Somatostatin and Octreotide in Bowel Obstruction: Pre-Clinic Al and Clinical Results

Malignant bowel obstruction is a common complication in patients with advanced abdominal or pelvic cancer. Whereas surgery should be considered in all cases of malignant bowel obstruction, many advanced and terminal cancer patients are considered unfit for surgery. In such patients with a short life expectancy, gastrointestinal symptoms such as nausea, vomiting, continuous and/or colicky pain, can be controlled by using a pharmacologic approach made up of analgesics, antiemetics and antisecretory drugs, without the use of a venting nasogastric tube. Among the antisecretory drugs, octreotide has been shown to reduce nausea and vomiting in bowel-obstructed patients owing to a reduction of gastrointestinal secretions, thus allowing in most patients removal of the nasogastric tube and the associated distress. Preclinical and clinical studies that demonstrated the role of somatostatin and octreotide in bowel obstruction are reviewed.

Somatostatin in inflammatory bowel disease

Intestinal inflammation is controlled by various immunomodulating cells, interacting by molecular mediators. Neuropeptides, released by enteric nerve cells and neuroendocrine mucosa cells, are able to affect several aspects of the general and intestinal immune system, with both pro- as well as anti-inflammatory activities. In inflammatory bowel disease (IBD) there is both morphological as well as experimental evidence for involvement of neuropeptides in the pathogenesis. Somatostatin is the main inhibitory peptide in inflammatory processes, and its possible role in IBD is discussed.

Pharmacological treatment of bowel obstruction in cancer patients

INTRODUCTION

Malignant bowel obstruction (MBO) is a common complication of advanced cancer, occurring most frequently in gynaecological and colorectal cancer. Its management remains complex and variable. This is in part due to the lack of evidence-based guidelines for the clinicians involved. Although surgery should be considered the primary treatment, this may not be feasible in patients with a poor performance status or advanced disease. Advances have been made in the medical management of MBO which can lead to a considerable improvement in symptom management and overall quality of life.

AREAS COVERED

This review emphasizes the importance of a prompt diagnosis of MBO with early introduction of pharmacological agents to optimize symptom control. The authors summarize the treatment options available for bowel obstruction in those patients for whom surgical intervention is not a feasible option. The authors also explore the complexities involved in the introduction of parenteral hydration and total parenteral nutrition in this group of patients.

EXPERT OPINION

It is not always easy to distinguish reversible from irreversible bowel obstruction. Early and aggressive management with the introduction of pharmacological agents including corticosteroids, octreotide and anti-cholinergic agents have the potential to maintain bowel patency, and allow for more rapid recovery of bowel transit. A combination of analgesics, anti-emetics and anti-cholinergics with or without anti-secretory agents can successfully improve symptom control in patients with irreversible bowel obstruction.

Review article: palliative care in gynecologic oncology

Patients with advanced gynecologic malignancies have a multitude of symptoms; pain, nausea, and vomiting, constipation, anorexia, diarrhea, dyspnea, as well as symptoms resulting from intestinal obstruction, hypercalcemia, ascites, and/or ureteral obstruction. Pain is best addressed through a multimodal approach. The optimum palliative management of end-stage malignant intestinal obstruction remains controversial, with no clear guidelines governing the choice of surgical versus medical management. Patient selection for palliative surgery, therefore, should be highly individualized because only carefully selected candidates may derive real benefit from such surgeries. There remains a real need for more emphasis on palliative care education in training programs.

Octreotide acetate enables the administration of chemoradiotherapy, including the oral anticancer drug S-1, in gastric cancer patients with malignant gastrointestinal obstruction

Advanced gastric cancer frequently results in the inability to ingest food or drink orally, a condition called malignant gastrointestinal obstruction (MGO). MGO is clinically defined as a gastrointestinal outlet obstruction caused by a large tumor, or malignant bowel obstruction with peritoneal dissemination. MGO impacts the quality of life by interfering with oral intake and by causing gastrointestinal symptoms, such as nausea, vomiting and abdominal pain. Octreotide acetate (OA) is an analogue of somatostatin which has been increasingly used to relieve gastrointestinal symptoms since it decreases the secretion of digestive juices and increases the absorption of water and electrolytes. In Japan, the oral anticancer drug S-1 was recently adopted as a key chemotherapeutic agent in advanced gastric cancer; however, its oral formulation precludes its utility in the MGO setting. This is a pilot study of chemoradiotherapy plus OA in gastric cancer with MGO. Patients were initially treated with OA to control gastrointestinal symptoms. Following resolution of their symptoms, the patients received chemotherapy with S-1 plus low-dose cisplatin and radiation. Irradiation was targeted at the primary tumor and surrounding lesions, including the lymph nodes. Grade 4 toxicity was observed in only 1 patient, and no treatment-related deaths were noted. After treatment, 3 patients achieved a partial response and 4 achieved stable disease. Of the 9 patients, 8 were able to tolerate solid food orally and were discharged. The outcomes of these cases suggest that OA is a useful adjunctive therapy that enables advanced gastric cancer patients with MGO to receive S-1-containing chemotherapy.

Acute pancreatitis, bacterial translocation, and different octreotide regimens: an experimental study

PURPOSE

To determine the effect of octreotide, octreotide with zinc, levamisole, and misoprostol on the bacterial translocation that develops in rats with acute pancreatitis (AP).

METHODS

A total of 36 rats were divided into six groups, each consisting of six rats. Only laparotomy was performed on the first group. Acute pancreatitis was performed on the second group. Octreotide was given to the third, fourth, fifth, and sixth groups. Octreotide, octreotide with zinc, levamisole, and misoprostol were given to groups III, IV, V, VI, respectively. Rats were euthanized 48 h after the occurrence of AP. Blood and mesenteric lymph node samples were collected for polymerase chain reaction (PCR). Pancreatic tissue and terminal ileum were obtained for histopathological examinations.

RESULTS

The severity of pancreatitis and mucosal damage of the terminal ileum was higher in group II than groups I, III, IV, V, and VI, histopathologically (P < 0.05). There wasn't a significant difference with respect to OA with Zn or L or M and OA group (P > 0.05). A significant difference was found in PCR positivity in blood and mesenteric lymph node between groups I and II (P < 0.05).

CONCLUSIONS

In AP, administering octreotide alone significantly prevented the bacterial translocation by preventing mucosal damage. The zinc, levamisole, or misoprostol with octreotide did not influence the results.

Efficacy of granisetron in the antiemetic control of nonsurgical intestinal obstruction in advanced cancer: a phase II clinical trial

The objective of this study was to assess antiemetic efficacy of granisetron in inoperable intestinal obstruction caused by advanced cancer. The study was open, prospective, and multi-centered. We assessed 24 patients (mean age: 61.3 years; 10 males, 14 females) with intestinal obstruction who were refractory to previous antiemetics. Obstruction involved the upper intestine in six patients, the lower intestine in three, and was at multiple levels in 15. Daily treatment included intravenous granisetron (3mg) and dexamethasone (8 mg); nasogastric drainage was not allowed. Subcutaneous haloperidol was available as rescue therapy. A numeric scale was used to evaluate nausea, pain, asthenia, and anorexia at baseline visit and every 24 hours up to the completion of four days of treatment (final visit). Treatment failure was defined as nausea >4 on the numeric scale, vomiting 2/day or more, and rescue therapy with haloperidol at 5mg/day or more. Of the 24 patients, 23 were evaluable for efficacy. Evaluation pre- vs. post-treatment indicated a significant decrease in the severity of nausea (score 6.9 vs. 0.8; P<0.001), number of episodes of vomiting (5.3 vs. 1.0; P<0.001), and abdominal pain (score 4.4 vs. 1.2; P<0.001). Nausea and vomiting control was achieved in 86.9% of patients. Although there was a trend toward greater efficacy in the lower and multiple levels of obstruction, the differences were not statistically significant owing, probably, to small sample size. We conclude that granisetron may be highly efficacious in the control of emesis resulting from intestinal obstruction caused by metastatic cancer, and can be used effectively in patients refractory to other antiemetics.

The effect of octreotide on healing of injured colonic anastomosis with immediate postoperative intraperitoneal administration of 5-Fluorouracil

PURPOSE

This study was designed to investigate the effect of octreotide on side effects of immediate usage of 5-fluorouracil after colonic anastomosis.

METHODS

Forty male Wistar rats were randomly assigned into four groups and underwent standardized left colonic anastomosis. The rats served as control or received intraperitoneal 5-fluorouracil (20 mg/kg daily), subcutaneous octreotide (20 mug/kg daily), or both. Diarrhea and wound complications were noted during the experiment. The colonic anastomoses were assessed for healing on postoperative Day 7 by determining the anastomotic bursting pressure, performing histologic examination, and measuring the tissue hydroxyproline content, serum malondialdehyde, and nitric oxide levels. Intraperitoneal adhesions and anastomotic leakage were also noted.

RESULTS

No statistical significant difference was found between the control and octreotide groups for each of the parameters measured. Immediate 5-fluorouracil use resulted with higher adhesion score (P = 0.002), significant depression in anastomotic bursting pressure (P = 0.0001), histopathologic score (P = 0.0001), hydroxyproline content (P = 0.0001), and increasing nitric oxide (P = 0.0001) and malondialdehyde levels (P = 0.0001) compared with the control group. Diarrhea was seen in 80 percent of the 5-fluorouracil group but in neither the control nor octreotide groups (P = 0.0001 for each comparison). However, all these parameters were ameliorated by use of concomitant octreotide and 5-fluorouracil (P = 0.019, P = 0.023, P = 0.0001, P = 0.006, P = 0.0001, and P = 0.013, respectively). In addition, diarrhea was found to be prevented (P = 0.0001).

CONCLUSIONS

The results of this study showed that concomitant octreotide use might prevent the side effects of 5-fluorouracil, such as diarrhea, postoperative adhesion, and delaying the anastomotic healing parameters. In addition, it might reduce tissue damage and inflammation.

Effects of octreotide acetate and Saccharomyces boulardii on bacterial translocation in an experimental intestinal loop obstruction model of rats

Intestinal obstruction (IO) induces bacterial translocation (BT) due to mucosal disruption, motility dysfunction, and increased intestinal volume, leading to bacterial overgrowth. This study was conducted to investigate the effects of octreotide acetate (OA) and Saccharomyces boulardii (SB) on the BT and intestinal integrity in an animal model of intestinal loop obstruction (LO). Forty adult male Sprague-Dawley rats (250-300 g) were randomized into 4 groups containing 10 rats each. Complete IO was created in the distal ileum of rats by a single 3-0 silk suture (LO). Group Sham: Sham (Laparotomy only was performed in this group); group LO: LO; group OA: LO plus OA (100 microg/kg, at 0, 12 hours of obstruction); group (SB): LO plus SB (800 mg/kg/day, via orogastric and preoperative for 3 days). After 24 hours, samples of mesenteric lymph nodes (MLN), liver, spleen and blood were obtained and cultured. The terminal ileum specimens were examined histopathologically. There were no BT in group Sham, but BT was noticed totally in 31 (77.5%) cultures in group LO. This rate was reduced to 30% (n = 12), 10% (n = 4) in the groups OA and SB respectively. Bacterial translocations of MLN and the liver in group LO were significantly higher than those of groups OA and SB. Bacterial translocations of the both spleen and blood in group LO were significantly higher than those of groups OA and SB. The mean bacterial counts, colony-forming units per gram tissue (cfu/g), in the MLN, liver and spleen of group LO were found significantly higher than those of groups OA and SB. The mean villus height in group OA was significantly higher than that of group LO and it in the group SB significantly higher than those of groups LO and OA. The present experimental study has demonstrated that OA and SB may have protective effects against BT in mechanical bowel obstruction and additionally SB preserves intestinal mucosal integrity.

Palliative management of malignant bowel obstruction

Bowel obstruction may be a mode of presentation of intra-abdominal and pelvic malignancy or a feature of recurrent disease following anticancer therapy. Malignant bowel obstruction is well-recognized in gynecologic patients with advanced cancer. Retrospective and autopsy studies found the frequency at approximately 5-51% of patients with gynecological malignancy(1-7). Malignant bowel obstruction (MBO) is particularly frequent in patients with ovarian cancer where it is the most frequent cause of death(7). Patients with stage III and IV ovarian cancer and those with high-grade lesions are at higher risk for MBO as compared to patients with lower stage or low-grade tumors(1,8). Ovarian carcinoma accounted for 50% of small bowel obstruction and 37% of large bowel obstruction treated in a large gynecological oncology service(8-11).

Effects of lanreotide on the healing of small bowel anastomoses following obstructive ileus in rats

PURPOSE: Lanreotide, a long-acting somatostatin analogue, inhibits intestinal, bile and pancreatic secretions and decreases intestinal motility. The purpose of this experimental study was to evaluate the effects of lanreotide on the healing of intestinal anastomoses following small bowel obstruction. METHODS: Two groups of 16 Wistar rats (average weight 310 g) were used. Basal diameters of ileus were measured prior to the ligation of the bowel, 15 cm from the ileocecal valve. Luminal fluid was also withdrawn proximal to the obstructed bowel for sodium and potassium analysis. Lanreotide was administered intramuscularly in a single dose (5.4 mg/kg) in the first group, while the same volume of saline was used in the control group. 48 h later rats were re-operated upon. Diameters of the obstructed segments were measured, and luminal fluid of the obstructed bowel was withdrawn and sodium and potassium levels were measured. A segment of 1 cm of the obstructed bowel was resected and end-to-end intestinal anastomosis was performed. Rats were sacrificed on day 7 following the second operation. Anastomoses were examined macroscopically and resected including a 2.5 cm of small bowel on either side. Bursting pressures were measured and the specimens were send for histological examination. RESULTS: The diameter of obstructed bowel increased significantly in both groups. The increase was more prominent in the control group (P < 0.001). Total luminal electrolyte contents for sodium and potassium were stastistically higher in the control group compared to the lanreotide group (P < 0.001). Adhesion formation was more extensive in the control group. Bursting pressures were significantly higher in the lanreotide group compared to the control group (P=0.003). Histological examination of anastomoses showed a more profound inflammatory reaction in the control group compared to the lanreotide group while microscopical healing of the anastomoses was almost the same in both groups. CONCLUSIONS: Lanreotide administration in rats with small bowel obstruction decreases significantly distension and electrolyte losses and seems to improve strength of small bowel anastomoses.

Role of octreotide, scopolamine butylbromide, and hydration in symptom control of patients with inoperable bowel obstruction and nasogastric tubes: a prospective randomized trial

Bowel obstruction may be an inoperable complication in patients with end-stage cancer. Scopolamine butylbromide (SB) and octreotide (OCT) have been successfully used with the aim of reducing gastrointestinal (GI) secretions to avoid placement of a nasogastric tube (NGT); however, there have been no comparative studies concerning the efficacy of these drugs. Furthermore, there is little information about the role played by parenteral hydration in symptom control of these patients. In a prospective trial that involved all 17 inoperable bowel-obstructed patients presenting to our services with a decompressive NGT, patients were randomized to OCT 0.3 mg/day or SB 60 mg/day for 3 days through a continuous subcutaneous infusion. Clinical data, survival time, and the time interval from the first diagnosis of cancer to the onset of inoperable bowel obstruction were noted. The intensity of pain, nausea, dry mouth, thirst, dyspnea, feeling of abdominal distension, and drowsiness were assessed by means of a verbal scale before starting treatment with the drugs under study (T0) and then daily for 3 days (T1, T2, T3). Moreover, daily information was collected regarding the quantity of GI secretions through the NGT, the oral intake of fluids, the quantity of parenteral hydration, and the analgesic therapy used. The NGT could be removed in all 10 home care and in 3 hospitalized patients without changing the dosage of the drugs. OCT significantly reduced the amount of GI secretions at T2 (P = 0.016) and T3 (P = 0.020). Compared to the home care patients, the hospitalized patients received significantly more parenteral hydration (P = 0.0005) and drank more fluids (P = 0.025). There was no difference in the daily thirst and dry mouth intensity in relation to the amount of parenteral hydration or the treatment provided (OCT or SB). Independent of antisecretory treatment, the patients receiving less parenteral hydration presented significantly more nausea (T0 P = 0.002; T1 P = 0.001; T2 P = 0.003; T3 P = 0.001) and drowsiness at T3 (P < 0.5). Pain relief was obtained in all 17 patients and only two patients required an increase in morphine dose at T1. All patients with inoperable malignant bowel obstruction should undergo treatment with antisecretory drugs so as to evaluate the possibility of removing the NGT. When a more rapid reduction in GI secretions is desired, OCT should be considered as the first choice drug. Parenteral hydration over 500 ml/day may reduce nausea and drowsiness.

THE EFFECT OF THE SOMATOSTATIN ANALOGUE OCTREOTIDE ON EXPERIMENTAL INTESTINAL OBSTRUCTION IN RATS

Background: Somatostatin has an inhibitory effect on the endocrine and exocrine secretions of the gut. It may have a beneficial effect in the conservative treatment of intestinal obstruction. The aim of the present study is to investigate the effect of octreotide in mechanical intestinal obstruction in rats. Method: Intestinal obstruction was induced in rats by ligation of a segment of the distal ileum. Animals were treated with the somatostatin analogue octreotide (n=16), or saline (n=16). Eight rats were operated but their intestine was not ligated (n=8) serving as sham controls. Forty eight hours after the operation, the animals were operated upon again and blood samples from the femoral vein were tested for electrolytes, urea, glucose, lactic acid, amylase, ph and bicarbonate. Portal vein blood samples were also obtained and tested for lactic acid and amylase. Results: Intestinal obstruction resulted, after 48 hours, in severe dilatation of bowel loops. A significant increase in plasma levels of urea, amylase and lactic acid was observed. Plasma pH decreased. In blood samples from the portal vein, a significant increase in lactic acid was observed, indicating metabolic acidosis, probably secondary to bowel ischemia. Octreotide treatment, resulted in less acidosis, with concomitant lower urea and lactic acid levels in the plasma and especially in the portal vein. Conclusion: Octreotide treatment may have a beneficial effect in the conservative treatment of selected cases of intestinal obstruction.

Somatostatin does not attenuate intestinal injury in dextran sodium sulphate-induced subacute colitis

FRom several in vitro and in vivo studies involvement of somatostatin (SMS) in intestinal inflammation emerge. Acute colitis induced in rats is attenuated by the long-acting SMS analogue octreotide. We studied the potential beneficial effect of SMS on non-acute experimental colitis. BALB/c mice received either saline, SMS-14 (36 or 120 microg daily) or octreotide (3 microg daily) subcutaneously delivered by implant osmotic pumps. A non-acute colitis was induced by administration of dextran sodium sulphate (DSS) 10% in drinking water during 7 days. DSS evoked a mild, superficial pancolitis, most characterized by mucosal ulceration and submucosal influx of neutrophils. Neither SMS-14 nor octreotide reduced mucosal inflammatory score or macroscopical disease activity, although reduction of intestinal levels of interleukin-1beta (IL-1beta), IL-6 and IL-10 during DSS was augmented both by SMS and octreotide. A slight increase of neutrophil influx was seen during SMS administration in animals not exposed to DSS. In conclusion, SMS or its long-acting analogue did not reduce intestinal inflammation in non-acute DSS-induced colitis. According to the cytokine profile observed, SMS-14 and octreotide further diminished the reduction of intestinal macrophage and Th2 lymphocyte activity.

Importance of vasoactive intestinal peptide and somatostatin for fluid losses in small-bowel obstruction

BACKGROUND

Previous observations have shown vasoactive intestinal peptide (VIP) to be an important secretagogue in the gut, whereas somatostatin has been reported to inhibit VIP release and fluid secretion.

METHODS

The possible role of VIP as mediator of the inflammation and fluid losses in obstructive ileus was investigated in vivo and in a chronic rat model with thread ligation of the jejunum. Extravasated Evans blue (Eb)-stained albumin was quantified by spectrophotometry. Net fluid secretion was measured by a gravimetric technique. VIP antiserum was used to inhibit the effects of endogenous VIP. A somatostatin analogue, octreotide, was used to inhibit the release of VIP.

RESULTS

Results showed a pronounced plasma Eb-albumin extravasation in the wall of the obstructed gut, which was significantly inhibited by VIP antiserum (p < 0.05) or octreotide (p < 0.01). Obstruction of the jejunum resulted in net fluid secretion that was significantly reduced by administration of octreotide (p < 0.01) or VIP antiserum (p < 0.05). Net fluid secretion in control animals remained constant.

CONCLUSIONS

These findings suggest that VIP is an important mediator of the pathophysiology in mechanical intestinal obstruction and that somatostatin may be involved in the endogenous control of fluid losses.

Effects of octreotide on healing of intestinal anastomosis following small bowel obstruction in rats

PURPOSE

Octreotide is an analog of somatostatin, with the same biologic effects but a longer half-life than somatostatin. The purpose of this experimental study was to search the effects of octreotide on the healing of bowel anastomosis and to observe the anatomic and physiologic changes in the obstructed bowel.

METHODS

Two groups of ten male Wistar albino rats (average weight, 250 grams) were used in this study. One group was the octreotide group, and the other was the control group. In both groups, the basal diameters of jejunum were measured before ligation of the bowel 20 cm from the duodenum. Octreotide was administered subcutaneously (7 micrograms/kg/day, in two equal doses) in the first group, and the same volume of saline was used in the control group. Diameters of the obstructed segments were measured, and sodium and potassium levels, obtained from the luminal fluid of the obstructed bowel, were recorded 48 hours following the first operation. Dilated segments were resected, and end-to-end intestinal anastomoses were performed. In rats sacrificed on the fourth and seventh days following the second operation, bursting pressures of the anastomotic and hydroxyproline levels in tissue samples taken from the anastomosis were measured.

RESULTS

The diameter of the obstructed bowel increased significantly in the control group (P < 0.05). Sodium and potassium losses were significantly less in the octreotide group (P < 0.001 for sodium; P < 0.01 for potassium). In histopathologic examination, ischemic changes were more evident in the control group (P < 0.05). Anastomotic bursting pressure differences were not significant on the fourth postoperative day (P > 0.05), but differences were significant on the seventh postoperative day (P < 0.05). Anastomotic tissue hydroxproline synthesis on the fourth and seventh postoperative days of the octreotide and control groups did not show significant difference (P > 0.05).

CONCLUSION

In this experimental model, it appears that octreotide attenuates the ischemic changes and electrolyte losses in the obstructed bowel.

Palliation of malignant intestinal obstruction using octreotide

Vomiting due to malignant intestinal obstruction is an unpleasant terminal event in many cancer patients, which responds poorly to conventional therapies. Somatostatin and its long-acting analogues reduce intestinal secretion. For this reason, octreotide was used in a phase I/II study of patients with intractable vomiting secondary to intestinal obstruction due to malignant disease. Vomiting was controlled or the volume of nasogastric aspirate was markedly reduced in 18 of 24 (75%) patients receiving a subcutaneous infusion of octreotide (median initial dose 300, range 100-600 micrograms/day) for a median of 9.4 (range 1-38) days. A further 2 patients had partial relief of their symptoms. Octreotide is an effective treatment of nausea and vomiting due to malignant bowel obstruction.

Treatment of acute postoperative ileus with octreotide

Our hypothesis was that postoperative ileus is caused by the release of neurotransmitters in the gut wall that inhibit motility. We reasoned that blocking the release with octreotide would prevent ileus. We placed serosal electrodes on the small intestine and stomachs of 15 dogs and inserted a duodenal cannula. After the animals recovered, electrical activity was recorded, and small bowel transit, colonic transit, and gastric emptying were studied radiographically and scintigraphically. Ileus was induced by celiotomy and intestinal abrasion. Dogs were randomized to receive on postoperative days 0 through 3 either a placebo (n = 5), octreotide, 1.5 micrograms/kg/8 hr subcutaneously (n = 5), or octreotide 0.83 micrograms/kg/hr intravenously (n = 5). Both doses of octreotide resulted in a faster return to preoperative values of small bowel interdigestive myoelectric activity and transit and colonic transit than did the placebo. The larger dose of octreotide, however, slowed gastric emptying. In conclusion, octreotide shortened the duration of postoperative ileus in the small bowel and colon of dogs.

Improvement in survival of mice with proximal small bowel obstruction treated with octreotide

Small bowel obstruction is a common disorder in surgical practice. The major morbidity of bowel obstruction relates to intestinal distension and ischemia. We hypothesized that octreotide, a potent inhibitor of gut secretion, would reduce mortality in a mouse model of lethal small bowel obstruction. C57 mice were anesthetized with urethane and prepared with either proximal jejunal or distal ileal obstruction. After 8 hours, surviving mice were randomized to receive either octreotide (100 micrograms/kg) or saline subcutaneously every 8 hours. Octreotide significantly improved survival in mice with proximal obstruction by life table analysis. Mean survival increased from 31 +/- 3 to 41 +/- 4 hours. In distal obstruction, octreotide treatment resulted in a trend towards improved survival; however, this trend failed to reach statistical significance by life table analysis. The improvement in survival in this mouse model suggests that octreotide may be a valuable adjunct in the treatment of patients with small bowel obstruction.

The therapeutic role of octreotide in the management of surgical disorders

The long-acting somatostatin analogue, octreotide, has recently been made available for clinical use in the United States. This novel synthetic peptide possesses a broad spectrum of physiologic actions primarily involving the inhibition of a variety of gastrointestinal and endocrine functions. Such actions have been utilized in the management of a variety of surgical disorders. Current understanding of the indications and efficacy of this agent in the treatment of surgical disease is reviewed.

Reoperation for small intestinal obstruction

Today, intestinal adhesions represent the most frequent etiology for complete or partial intestinal obstruction. Although partial obstruction can be treated nonoperatively with a considerable likelihood of success, intestinal strangulation cannot uniformly be predicted or prevented. Complete intestinal obstruction is associated with a significant incidence of strangulation if not treated by a vigorous surgical approach. Consequently, complete intestinal obstruction secondary to adhesions is still a surgical disease. Attempts at control of the adhesion process include mechanical methods to prevent subsequent obstruction and chemical methods to prevent the adhesion process itself. The invasive mechanical methods appear dated. A variety of agents have been used either systemically or in the peritoneal cavity to prevent the establishment of intra-abdominal adhesions. Agents that do not contribute to subsequent morbidity or impede the native host defense mechanisms should be utilized. High-molecular-weight dextran and nonsteroidal anti-inflammatory agents show some promise of being both safe and effective. As is frequently the case, the bottom line in preventing and treating intra-abdominal adhesions is appropriate surgical technique. Intestinal adhesions can be related clearly to leaving damaged, devitalized, or ischemic tissue in the peritoneal cavity or to excessive roughness in handling of tissues. Steps such as avoidance of excessive suture material and unnecessary handling of the bowel will do much to prevent subsequent adhesion generation. Likewise, the surgical lysis of intraperitoneal adhesions is frequently fraught with complications such as intra-abdominal abscess or postoperative incisional failure. This is again related to surgical technique and most directly to the use of blunt dissection to divide adhesions. Knife dissection in the lysis of adhesions is recommended. This technique, combined with excellent intraoperative hemostasis, can be associated with a marked diminution in the incidence of postoperative fistulas and abscesses.