Fibrin glue improves the healing of irradiated bowel anastomoses

Many surgeons are reluctant to construct a bowel anastomosis with irradiated intestine. Previous studies have demonstrated diminished tensile strength of rat small bowel anastomoses that have been irradiated intraoperatively. To determine whether fibrin glue, a known tissue adhesive, improves the healing of these anastomoses, 69 male Sprague-Dawley rats were randomized into three anastomotic groups: Group 1, sutured ileal anastomosis without radiation or fibrin glue; Group 2, irradiated sutured ileal anastomosis without fibrin glue; and Group 3, irradiated ileal anastomosis with fibrin glue added to the suture line. Groups 2 and 3 received a single dose of 2,000 R intraoperatively. At seven days, the rats were sacrificed and the anastomotic segment was tested for breaking (tensile) strength. Anastomotic collagen content was evaluated using a hydroxyproline assay. Tensile strength results demonstrated that Group 2 was significantly weaker than Groups 1 and 3 (P=0.001) and that the hydroxyproline content of Group 3 was significantly greater than that of Group 2 (P=0.015). These results show that the addition of fibrin glue to an intraoperatively irradiated small bowel anastomosis improves healing, as demonstrated by both tensile strength and hydroxyproline content studies.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.This work was supported in part by the Bowman Research Fund.     

Anastomotic compression button: A new mechanical device for sutureless bowel anastomosis

The anastomotic compression button is a new mechanical device that uses three interlocking polypropylene buttons to produce a sutureless bowel anastomosis. The device is unique in that it allows application of the buttons via a device similar to the popular intraluminal stapler, but it leaves no staples or foreign body of any kind in the bowel wall. The authors compared the 25-mm anastomotic compression button with the 25-mm intraluminal stapler in the colon of dogs. After 28 days, the mucosal blood flow, burst pressure, and anastomotic indices were found to be identical between the anastomotic compression button and the stapler. The anastomotic compression button was easier to use, and microscopic examination showed less ulceration, fibrosis, and inflammation, and better re-epithelialization at the anastomotic compression button site. The anastomotic compression button appears to have the potential to be a superior method compared with stapled anastomoses in the colon.Supported by Deknatel, A Division of Pfizer Incorporated, Fall River, Massachusetts.     

Effect of intraoperative radiation on the tensile strength of small bowel anastomoses

Increasing interest in the use of preoperative or intraoperative radiation therapy for cancer has led to concerns regarding tissue healing and integrity subsequent to treatment. This is especially so for intestinal anastomoses incorporating irradiated bowel, where poor healing may lead to anastomotic disruption and sepsis. One hundred thirty Sprague-Dawley rats were randomized into five groups as follows: both limbs, one limb, or neither limb of an anastomosis received 2,000 R of radiation intraoperatively. A fourth group had a segment of small bowel irradiated, with no anastomosis; a fifth group had the gut exposed by celiotomy. The control groups and all anastomoses underwent tensile strength measurements on the seventh postoperative day, with findings as follows: no anastomosis, no irradiation, 143.75 g; no anastomosis, irradiated, 114.50 g; anastomosis, no irradiation, 85.273 g; anastomosis, one limb irradiated, 78.100 g; anastomosis, both limbs irradiated, 59.00 g. There was no statistical difference in tensile strength of the anastomosis between when neither limb and when just one limb was irradiated. However, when both limbs were irradiated, the loss of strength was statistically significant ( P =0.002). Irradiation damage scores were assigned using Black et al. 's histologic scoring system. These scores were not significantly different between the irradiated segments. Inflammation and fibrosis scores for the anastomoses were also not significantly different. These results indicate that, in rats, anastomotic healing is impaired only when both limbs of the anastomosed intestine are irradiated. The normal strength of the anastomosis with only one limb irradiated cannot be explained by differences in inflammation, fibrosis, or radiation damage and is caused by an undetermined factor.Poster presentation at the meeting of The American Society of Colon and Rectal Surgery, St. Louis, Missouri, April 29 to May 4, 1990.This work was supported in part by the Bowman Research Fund.     

Stapled colonic J-pouch-anal anastomosis without a diverting colostomy for rectal carcinoma

PURPOSE: Colonic J-pouch reconstruction is designed to improve functional outcome of coloanal anastomosis. Most surgeons use a diverting colostomy to avoid severe pelvic sepsis caused by anastomotic breakdown. METHODS: We report the outcome of 30 consecutive patients with colonic J-pouch-anal anastomosis without a diverting colostomy performed between November 1992 and October 1993. All patients had carcinoma of the lower two-thirds of the rectum. Patients were seen every three months. Functional results were compared with those of 21 rectal cancer patients with straight coloanal anastomosis who underwent surgery in the same period and 20 normal patients. RESULTS: There were two anastomotic leakages and one postoperative death. After one year, patients with pouch anastomosis had significantly less frequency of defecation and rectal urgency compared with those with straight anastomosis (P <0.01); 48 percent of patients with straight anastomosis had more than five bowel movements per day, whereas all patients with pouch anastomosis had five or less bowel movements per day. Manometric studies showed maximum tolerable volume was significantly higher in patients with pouch anastomosis (81 vs. 152 ml;P <0.01). CONCLUSIONS: Stapled colonic J-pouch-anal anastomosis without a diverting colostomy is a reliable procedure that provides good, long-term functional results.Supported by National Science Council, Taiwan, Research Grant NSC 83-0412-B182-021.Read at the meeting of the International Society of University Colon and Rectal Surgeons, Singapore, Singapore, July 2 to 6, 1994.     

Treatment of colorectal and ileoanal anastomotic sinuses

PURPOSE: This study is designed to describe a technique and report results for treating low anastomotic sinuses. METHODS: Restorative proctocolectomy and complicated low anterior resections were protected with diverting loop ileostomy. Contrast enemas identified anastomotic problems before ileostomy closure. Pouch-anal or colorectal anastomotic sinuses that failed to resolve with observation were treated before intestinal continuity was restored. With the patient receiving regional or general anesthesia, a rigid proctoscope or anoscope was used to identify the sinus opening. The common wall between the sinus and the bowel lumen was divided under direct vision with laparoscopic cautery scissors, and the sinus cavity was debrided with a suction cautery wand placed through the scope. RESULTS: Six patients with anastomotic sinuses have received outpatient treatment in the described manner during the past two years. Four patients had restorative proctocolectomies for ulcerative colitis, and two had low anastomosis for rectal cancer. Three patients presented with pelvic sepsis before the contrast study; the remainder were asymptomatic. Division of anastomotic sinus was performed one to eight months after diagnosis of the sinus. Following division, anastomotic cavities resolved in five patients by 1 month and in one patient by 12 months. In these six patients, there was one dilatable anastomotic stricture but no other anastomotic complications at follow-up 5 to 16 (mean, 9.2) months after sinus division. CONCLUSION: When used in conjunction with fecal diversion, sinus unroofing by division of the common wall between the sinus and bowel lumen treats low pelvic sinuses.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996, and at the Tripartite meeting, London, United Kingdom, July 8 to 10, 1996.     

Is mechanical bowel preparation necessary before primary colonic anastomosis?

The necessity of preoperative or intraoperative mechanical bowel preparation of the colon, before primary anastomosis, has been recently challenged in clinical elective and emergency situations. PURPOSE: This experimental study in dogs investigated the safety of segmental resection and primary anastomosis in the unprepared or loaded colon. METHODS: Two segments of the descended colon were resected and anastomosed in each animal. Group I (12 anastomoses) received preoperative mechanical bowel preparation; the colon was not prepared in Group II (16 anastomoses); in Group III (12 anastomoses), a preliminary distal colonic obstruction was produced, and during the subsequent resection the colon was loaded. Postoperatively, animals were observed clinically, and anastomoses were assessed at autopsy on the ninth day. RESULTS: All animals recovered uneventfully. At autopsy there was no evidence of anastomotic leakage. CONCLUSIONS: In light of recent clinical reports and this experimental study, the ritual of mechanical bowel preparation should be further scrutinized.     

Effect of an omental wrap on the healing and vascularity of compromised intestinal anastomoses

Adult Wistar rats were used to investigate the ability of an omental wrap to limit leakage from compromised intestinal anastomoses. Under ketamine anesthesia, a section of small bowel was divided and then reanastomosed using a control anastomosis, a deficient anastomosis, or an ischemic anastomosis, plus or minus the addition of a wrap of omentum. Initially 10 rats were randomly assigned to each group. Nineteen of the 20 rats with unwrapped compromised anastomoses died within six weeks, compared with five deaths in the rats protected by an omental wrap (Fisher's exact test;P < 0.01). The experiment was then repeated with a sample of rats from each anastomotic group being sacrificed for histologic examination on days 2 to 7, 10, 14, and 42. At the time of sacrifice a dye was injected into the omental vasculature to determine its contribution to the healing anastomosis. An anastomosis could be demonstrated between omental and bowel wall vessels by the third postoperative day. At one week the infarcted bowel edges were being resorbed and the omentum formed a fibrotic cylinder aligning the separated ends of bowel wall. At six weeks the scar became more contracted and the bowel mucosa had started to grow onto its luminal surface. It is concluded from this study that the omental wrap is protective to a compromised anastomosis by providing a biologically viable plug to prevent early leakage and a source of granulation tissue and neovasculature for later wound repair.     

Intraluminal bypass technique using a condom for protection of coloanal anastomosis

PURPOSE: Most surgeons carry out temporary diverting colostomy in coloanal anastomosis for mid-rectal or lower-rectal carcinomas. It has been reported that proximal fecal diversion provides no guarantee against anastomotic leaks. Some have proposed the use of the intracolonic bypass tube to prevent anastomotic leakage and colostomy, but colonic necrosis has been reported; it is important to use a safe technique that obviates this. METHODS: The rectum is fully mobilized and transected at the level of the levator diaphragm. The mobilized sigmoid and rectum are resected with their mesenteries, and the prepared distal colon is everted 5 cm using Babcock clamps. The ring of a sterilized condom is then sutured to the mucosa and submucosa of the colon with 4/0 chromic catgut sutures. After completion of coloanal anastomosis, the condom is brought to the exterior, and the mid part is transected. RESULTS: We have used a condom for intraluminal bypass procedures in ten rectal carcinoma patients including five preoperative radiation cases. There was no anastomotic dehiscence, leakage, or colonic necrosis because of a condom. CONCLUSION: We believe that the intraluminal bypass technique using a condom is a very safe, cost-effective, and easily available alternative for coloanal anastomosis.Read at the meeting of the Korean Colo-Proctological Society, Pusan, South Korea, December 4, 1993.     

New technique for Hartmann's reconstruction

Since the introduction of Hartmann's operation and its broader applications, restoration of intestinal continuity has posed technical challenges and significant morbidity. We describe a technique for Hartmann's reconstruction, utilizing a circular anastomotic stapling device that is simple and fast and that minimizes the potential for contamination, in which the bowel lumen remains closed at all times.     

The influence of NSAIDs on experimental intestinal anastomoses

Limiting degradation of collagen during the initial phase of wound healing is expected to improve postoperative intestinal strength and thereby decrease chances for anastomotic dehiscence. We studied the influence of four nonsteroid anti-inflammatory drugs on the healing of intestinal anastomoses in rats, with special regard to changes of collagen levels around the anastomoses. Four experimental groups of 20 rats each received daily oral doses of piroxicam, ibuprofen, aspirin, or indomethacin and were compared with a control group. Animals were sacrificed 3 or 7 days after operation. Both morbidity and mortality rate in the experimental groups were high. Collagen, measured as hydroxyproline, levels in anastomotic and adjoining 1-cm intestinal segments were compared with concentrations in control segments resected during operation. After an initial decrease on day 3, hydroxyproline concentrations increased on day 7. In the colon the lowering of hydroxyproline concentrations, which was more pronounced than in the ileum, was significantly reduced by administration of piroxicam and ibuprofen, both in the anastomosis and its proximal segment. On day 7, the increase of hydroxyproline concentrations in the ileum was inhibited by administration of anti-inflammatory drugs. It is concluded that nonsteroidal anti-inflammatory drugs may limit postoperative degradation of collagen in colonic anastomoses, but at the same time may increase the rat's susceptibility to surgical infections.     

Are intersecting staple lines a hazard in intestinal anastomosis?

To determine the safety of intersecting staple lines, 22 pigs were operated upon with a functional end-to-end enteroanastomosis 40 cm distal to the ligament of Treitz using linear stapling devices. The procedure was repeated on the colon, where a colocolostomy was created. The blood flow at intersecting staple lines and single-row staple lines for each anastomosis was studied with the reference organ method 24 hours after the first operation. The purpose was to evaluate whether there is a reduction in blood flow at the site of intersecting staple lines, causing an increased risk for anastomotic leakage. The reduction in mean blood flow in crossing compared with noncrossing staple lines was 6 percent (–5–17 percent) for small bowel anastomoses and 7 percent (–6–19 percent) for colonic anastomoses. An equivalence test showed that, if a reduction in blood flow exists between crossing and noncrossing staple lines, it is most likely less than 30 percent (P <0.001) for both small bowel and colonic anastomoses. This experimental study demonstrates that intersecting staple lines in small bowel and colonic anastomoses do not reduce anastomotic blood flow to a dangerous level.This study was supported by grants from Johnson & Johnson Sweden AB and The Medical Faculty, Lund University, Lund, Sweden.     

Experience with the biofragmentable anastomotic ring (BAR) in bowel preoperatively irradiated with 6000 rad

Previous studies from the authors' laboratory using the biodegradable anastomotic ring (BAR) have demonstrated the safety of this device in animals irradiated preoperatively with the equivalent of 5000 rad; sutured, stapled, and BAR anastomoses all had leak rates of 10 percent or less in this setting. This study was undertaken to assess the safety of the BAR after irradiation with the equivalent of 6000 rad. Thirteen mongrel dogs underwent preoperative irradiation to the rectum and rectosigmoid, receiving 6000 rad according to the nominal standard dose equation. After a three-week rest period, each dog underwent anterior resection of the rectosigmoid and anastomosis with the BAR. The anastomoses were evaluated for early and late healing and anastomotic leaks. The results were compared with previous data from the authors' laboratory using an identical model. Radiographic leaks were found in 7 of 10 sutured anastomoses, 8 of 10 stapled anastomoses, and 3 of 13 BAR anastomoses (P < 0.01). Comparative clinical leaks were 5 of 10 for sutured, 5 of 10 for stapled, and 3 of 13 for BAR anastomoses. These data suggest that the BAR may offer added safety to an anastomosis after preoperative irradiation. Whether this effect is due to the atraumatic technique of placing the device, improved blood flow to the anastomotic margins, or other factors, is still undetermined.     

Stapled stricturoplasty for Crohn's disease

PURPOSE: Stricturoplasty was originally used to treat multiple fibrotic strictures of tuberculosis. As the pendulum of treatment of Crohn's disease swung toward conservatism and bowel preservation, stricturoplasty was performed in Crohn's disease. Stricturoplasty can be used when there is limited, well-localized disease and should be avoided in the presence of grossly inflamed or infected material. We describe a new technique of stricturoplasty. METHODS: Typically stricturoplasty is performed in a manner similar to a Heineke-Mikulicz pyloroplasty. A stapled stricturoplasty technique has been previously described, but in actuality these are more similar to a bypass procedure. Our technique uses a stapled, open technique similar to the triangulating method of bowel anastomosis. This was performed in one patient to correct six strictures. RESULTS: Our patient did well postoperatively and developed no significant complications. He has no evidence of recurrent strictures. CONCLUSION: We describe a stapled stricturoplasty technique that is truly a stricturoplasty because the bowel lumen is increased; it is similar to the triangulating method of end-to-end stapled bowel anastomosis. It is safe, efficient, and effective. Additionally, it allows radiographic location of the stricturoplasty site, thus allowing determination of effectiveness of the procedure as well as recurrence.Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994.     

Influence of myectomy,ileal valve,and ileal reservoir on the ecology of the ileum

Fecal bacteriology, fecal volatile fatty acids, and ileal mucosal morphology were studied in dogs after ileoanal anastomosis alone, ileoanal anastomosis and myectomy, ileoanal anastomosis and myectomy with ileoileal valve, and ileoanal anastomosis with duplicated (J) ileal reservoir. The ratio of anaerobes to aerobes was significantly less in stool from dogs which had undergone ileoanal anastomosis compared with each of the other three groups ( P <0.01). The numbers of streptococci and clostridia both were significantly less in stool from dogs with ileoanal anastomosis alone than in any other group. The concentrations of fecal acetic and propionic acids were significantly less in dogs with ileoanal anastomosis alone than in any other group ( P <0.05), but there were no significant differences in the concentrations of fecal butyric or valeric acids. The severity of mucosal inflammation and degree of villous atrophy were more marked in the ileum of J reservoirs ( P <0.01), and the percentage of stool retained after defecation was greater ( P <0.05) in dogs with J reservoirs than in any other group. Therefore, the use of myectomy resulted in significant changes in the ecology of the distal ileum although changes typical of pouchitis were seen only in dogs with J reservoirs.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.Supported in part by a grant from the Special Trustees Fund, University of Leeds.     

Healing of ischemic colonic anastomosis: Fibrin sealant does not improve wound healing

Fibrin adhesives have been advocated as a protective sealant in high-risk colonic anastomoses to prevent leakage. To assess the effect of fibrin glue sealing on the healing ischemic anastomosis, we compared the healing of sutured colonic anastomoses in the rat, with and without fibrin adhesive (Groups IA and IB), and ischemic anastomoses with and without fibrin adhesive (Groups IIA and IIB). On days two, four, and seven, 10 animals in each group were sacrificed. Adhesion formation was scored, and the in situ bursting pressure was measured. The collagen concentration and degradation were estimated by measuring hydroxyproline. Adhesion formation was more prominent in Groups IB, IIA, and IIB on day four only; abscesses were noted in the ischemic group in four rats. Anastomotic bursting pressure was significantly lower in sealed (IB) and ischemic anastomoses (IIA) than in normal anastomoses (IA) on day four. Sealing of ischemic anastomoses did not change bursting pressures on days two, four, and seven. The relative decrease of collagen in the sealed anastomoses is significantly higher on day four only. It is concluded that sealing of normal colonic anastomoses in the rat has a negative effect on wound healing. Ischemia at the anastomotic site results in weaker anastomotic strength on day four postoperatively. Also in ischemic anastomoses, fibrin sealant does not improve wound healing during the first seven days. Adhesion formation on ischemic intestinal anastomoses was not prevented by fibrin sealing.     

Intraoperative colonic lavage in nonelective surgery for diverticular disease

BACKGROUND: Staged resection of the sigmoid colon has been the traditional strategy for treating patients who require nonelective surgery to manage complications of diverticular disease. Resection and primary anastomosis has not generally been recommended when the clinical setting is compromised by contiguous inflammation or inadequate mechanical cleansing of the colon because of concerns regarding the potential risk of anastomotic dehiscence. Although many reports have confirmed that intraoperative colonic lavage (ICL) is a safe method for relieving fecal loading of the colon to facilitate primary intestinal anastomosis in patients with mechanical obstruction of the distal colon, there is very limited experience with the use of this technique in treating acute inflammatory disorders of the colon. In this report, we present our results with ICL in the nonelective treatment of patients with complications of diverticulitis. METHODS: Records of all patients undergoing urgent operations at the Lahey Clinic to treat complications of diverticular disease from July 1987 to January 1996 were reviewed. RESULTS: Of 62 patients who required nonelective operations, 33 underwent ICL in an attempt to perform primary anastomosis. In five patients, the operation included creation of a colostomy. The indication for surgery was obstruction in 13 patients (39 percent), persistent abscess or phlegmon in 13 (39 percent), perforation in 6 patients (18 percent), and hemorrhage in 1 patient (3 percent). According to Hinchey's classification system, 18 patients had Stage I disease, 10 had Stage II, and 5 patients had Stage III disease. There were no patients with Stage IV disease. The single anastomotic complication in the series was responsible for the sole operative mortality. The morbidity rate of 42 percent, included three intraoperative complications (2 splenic injuries and 1 ureteral laceration), two intra-abdominal abscesses (6 percent), and six wound infections (18 percent). CONCLUSION: In our experience, ICL has proven to be a safe method for accomplishing single-stage resection of the colon in selected patients with diverticulitis who require an urgent operation. When there is no evidence of diffuse purulent or feculent peritonitis, we believe this is the preferred method for treating patients who are hemodynamically stable. Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.     

Stricture at the pouch-anal anastomosis after restorative proctocolectomy

PURPOSE: The aim of this study was to determine what factors may be responsible for the development of a stricture at the pouch-anal anastomosis after restorative proctocolectomy. METHODS: A consecutive series of 115 patients was studied retrospectively a median of 34 months (range, 4–100 months) after operation or ileostomy closure. The procedure failed in 11 patients (9.6 percent) who subsequently had to have a permanent ileostomy. Another two patients were excluded from the analysis, one of whom was awaiting ileostomy closure, whereas the other had a stricture due to a desmoid tumor. Of the remaining 102 patients, 39 (38 percent) developed an ileoanal anastomotic stricture, which was severe and persistent in 16 percent. RESULTS: The results were analyzed with the aid of multivariate logistic regression analysis. Factors which predisposed significantly to the development of an ileoanal anastomotic stricture were 1) use of the 25-mm (small) diameter stapling gun (P<0.05), 2) use of a quadruplicated reservoir (P=0.05), 3) use of a defunctioning ileostomy (P=0.03), and 4) anastomotic dehiscence and pelvic sepsis (P=0.03). The single patient whose operation failed because of a stricture had also developed pelvic sepsis associated with an anastomotic dehiscence. CONCLUSIONS: The eventual clinical, functional outcome after dilation of a stricture in the 39 patients who developed a stricture was as good as the outcome in the 63 patients who did not a develop stricture.     

What happens to the Valtrac® anastomosis of the colon?

Late results after colonic anastomoses performed with the biofragmentable anastomosis ring (BAR; Valtrac ^®; Davis & Geck, Wayne, NJ) were evaluated in 30 patients who had undergone a left-sided colonic or rectosigmoid anastomosis a mean of 24.5 (range, 12–38) months earlier. Patients were asked about their late postoperative recovery and their bowel habits. A barium enema was performed, and then a flexible endoscopy was done, during which the anastomotic area was evaluated both in macroscopic terms and histologically. One of the patients had died, and three refused to participate in the investigation. Of the remaining 26 patients, one had been reoperated on 22 months after the primary sigmoid resection. The reason for reoperation was an anastomotic stricture. One of the patients was admitted to the hospital during the study and was operated on for reasons not related to the anastomosis. Twenty-four patients underwent the study scheme. All had recovered uneventfully. Sixteen anastomoses could not be identified radiologically and seven not even during endoscopy. Histologically, there was mild-to-moderate fibrosis and scarring in 17 anastomoses, and, in the seven that could not be identified, only normal colonic mucosa was found. The late results of BAR anastomoses are satisfying, and the rate of complications is acceptable.     

Efficacy of radioprotective agents in preventing small and large bowel radiation injury

PURPOSE: A variety of adjuvant treatments and cytoprotective agents have been proposed to lessen the toxicity of radiation therapy. The following study was designed to evaluate the benefit of six agents or combinations using anastomotic bursting strength as a measure of transmural radiation injury. METHODS: The 40-Gy study consisted of the following. Seventy-two male Sprague-Dawley rats were divided into eight equal groups: nonradiated control, radiated untreated control, and six radiated treated groups. The radioprotective treatments included ribose-cysteine (RibCys), WR-2721, glutamine, vitamin E, MgCl₂/adenosine triphosphate, and RibCys/glutamine in combination. Radiated animals received 40 Gy to the abdomen. Two weeks after radiation, all animals underwent small bowel and colonic resection with primary anastomosis. Animals were sacrificed one week postoperatively, at which time anastomoses were evaluated and bursting strengths determined. The 70-Gy study consisted of the following. The same protocol was repeated for five groups of nine rats divided into nonradiated, radiated untreated, and three radiated treated groups receiving RibCys (8 mmol/kg), RibCys (20 mmol/kg), and WR-2721. All radiated animals received 70-Gy doses. RESULTS: In the 40-Gy group, there were 10 radiation-related deaths and 6 anastomotic leaks among 70 rats studied. None of the differences between groups were significant. Nonradiated control group small bowel and large bowel anastomotic bursting pressures were significantly elevated compared with all radiated groups. Compared with radiated controls, there were significant improvements in small bowel bursting strength in the RibCys, WR-2721, RibCys-glutamine, and vitamin E groups and significant improvement in colonic bursting strength in MgCl₂/adenosine triphosphate, WR-2721, and RibCys groups. In the 70-Gy group, all nine nonradiated control rats survived. All eight untreated radiated control rats died, four of eight WR-2721 animals died (P=0.03), all RibCys (8 mmol/kg) animals died (P=0.03), and three of nine treated with RibCys (20 mmol/kg) survived (P=0.08). CONCLUSIONS: WR-2721 and RibCys gave consistent protection against large and small bowel radiation injury. The lower incidence of treatment-related toxicity and potentially equal or greater radioprotective effects may make RibCys more clinically useful than WR-2721.Supported by the 1993 ASCRS/ETHICON Surgical Research Fellowship Award and the Minneapolis Medical Research Foundation. Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994.     

Effects of an intra-abdominal latex (drain-like) tube on anastomotic resistance and adhesion formation in a rat model

PURPOSE: Aim of the present study was to determine effect of a latex drain on colonic resistance and its relation to adhesion phenomena. METHODS: Forty Sprague-Dawley rats were divided into two groups (n=20): Group 1, simple colonic anastomosis; and Group 2, colonic anastomosis with drain ad latum. Rats were sacrificed four days after surgery, and adhesions were evaluated. Segment containing anastomosis was removed, and bursting pressure was determined. RESULTS: General adhesion scores in Group 2 were higher than in Group 1 (P =0.002). Score for adhesions to anastomotic line in Group 1 was higher than in Group 2 (P =0.016). Bursting pressure was significantly lower in Group 2 (Group 1, 67.90±31.39 mmHg; Group 2, 46.95±29.69 mmHg;P =0.034). In all cases, leakage of dye was observed at the anastomotic line. A multiple regression test was applied to both groups (40 cases), taking bursting pressure as the dependent variable and other parameters as independent variables. A strong relationship appeared to exist between anastomotic resistance and fraction of anastomotic line that was covered by the neighboring organ (P <0.001). CONCLUSIONS: Placing a latex drain near a colonic anastomosis is associated with local inhibition of spontaneous adhesions to anastomotic line and, therefore, to significantly decreased resistance.Supported in part by the Asociación Médica para la Investigación y Docencia en Albacete (A.M.I.D.A), Spain.