Left Colonic Anastomosis Research Articles

The Effects of Resveratrol on the Healing of Left Colonic Anastomosis

Introduction: Resveratrol (RSV) is a natural polyphenolic compound found in grape skins and the red wine which improves histological reorganization of the regenerating tissue in dermal wound healing. Since anastomotic healing possesses paramount importance to prevent complications in colorectal surgery, the present study is aimed to evaluate the effect of RSV on the healing of experimental left colonic anastomoses. Methods: Thirty-two male Wistar albino rats were randomized into two groups and subjected to colonic anastomosis. The study group was treated with RSV and the control group received tap water instead. The rats were sacrificed 3 and 7 days postoperatively. Wound complications, intra-abdominal abscesses, and anastomotic leaks and stenosis were recorded. Four types of assessment were performed: bursting pressure, hydroxyproline (OHP) content, histopathology, and biochemical analysis. Results: Compared to the control group, the RSV-treated rats displayed a higher bursting pressure (p <. 001) and anastomotic OHP content (p <. 05)]. RSV treatment leads to significant increase in PON activity at both time points and decrease in malondialdehyde levels on postoperative day 3 (p <. 001). Histopathological analysis revealed that RSV administration leads to a better anastomotic healing in terms of mucosal ischemia, neovascularization, reepithelialization, fibroblast, and lymphocyte infiltration. Conclusion: The study results suggest that exogenous RSV administration exerts a positive effect on experimental colonic wound healing in the rat. Although the precise cellular mechanisms by which RSV enhances anastomotic wound healing is not clear, stimulation of neovascularization, generation of collagen synthesis, inhibition of overinflammation, and restriction of oxidative injury seems to be of paramount importance.

Effect of 2-Octyl-Cyanoacrylate on Ischemic Anastomosis of the Left Colon

Introduction: 2-octyl-cyanoacrylate may be a good alternative in ischemic colon anastomosis without impairment of tissue perfusion. Methods: Forty male Wistar albino rats were randomized into four experimental groups (n = 10 in each group). In group 1 (control), a well-perfused left colonic segment was transected, and free ends were anastomosed by propylene sutures. In groups 2, 3, and 4, the animals underwent a standardized surgical procedure to induce ischemic left colon anastomosis. In group 2, an end-to-end anastomosis was created using six interrupted 6-0 polypropylene sutures between ischemic edges. In group 3, after approximating the mesenteric and antimesenteric edges of the anastomosis with two 6-0 polypropylene sutures, 2-octyl-cyanoacrylate was applied between the edges. In group 4, anastomosis was created by the same technique as described in group 2, and additionally 2-octyl-cyanoacrylate was applied on suture line. Rats were killed on day 4 following operation. Anastomotic integrity, intraperitoneal adhesion scores, anastomotic bursting pressures, and tissue hydroxyproline levels were recorded. Histopathological examination of the anastomosis was also performed. Results: There were no statistically significant differences among groups with respect to anastomotic integrity (p =.142). The mean bursting pressure values were 81.1 ± 23.83, 43.3 ± 26.06, 15.8 ± 11.3, and 17.6 ± 18.02 in groups 1, 2, 3, and 4, respectively. There were no statistically significant differences among groups 2, 3, and 4 with respect to tissue hydroxyproline levels and bursting pressure levels. The highest adhesion scores were observed in groups 3 and 4. Discussion: 2-octyl cyanoacrylate does not have additional advantages in the healing of experimental ischemic colon anastomosis.

Does Low Molecular Weight Heparin Impair Anastomotic Wound Healing?

BackgroundEnoxaparin is an important molecule which had been using in prophylaxis and treatment of deep venous thrombosis. Also, it is showed that it prevents postsurgical peritoneal adhesions in rats. It is aimed to evaluate its effects on gastrointestinal wound healing. MethodsThirty Wistar albino rats were divided into three groups as control, subcutan, and intraperitoneal enoxaparin groups. Left colon anastomoses were performed. On postoperative seventh day, anastomotic healing was evaluated by measuring anastomotic bursting pressure, tissue hydroxyproline levels, and histopathological examination. ResultsThe anastomotic bursting pressure was highest in subcutan enoxaparin group (p < 0.001), intraperitoneal enoxaparin group (p < 0.01) came the second, and the control group has the worst value. The hydroxyproline results were found nearly similar to the bursting pressure values (subcutan (p < 0.001) > intraperitoneal (p < 0.05) > control). Neovascularization in subcutan group (p < 0.001) has a statistically significant difference to other groups. ConclusionEnoxaparin did not interfere with colonic anastomotic resistance but improved the intestinal wound healing.

The Effects of Intraperitoneal Sildenafil Administration on Healing of Left Colonic Anastomoses and Intra-Abdominal Adhesion Formation in the Presence of Intra-Abdominal Infection

The objective of this pilot study was to establish an animal model for intra-abdominal infection and to examine the effect of sildenafil on anastomotic healing of the left colon and intra-abdominal adhesion formation. Fourteen Winstar rats underwent colonic transsection and primary anastomosis after performing intra-abdominal infection. Rats were divided into two groups: Group 1 (n = 7): intra-abdominal infection, resection, and anastomoses; Group 2 (n = 7): intra-abdominal infection, resection, anastomoses, and sildenafil. Anastomotic bursting pressures, hydroxyproline levels, histopathologic grading, and abdominal adhesions were accessed on the postoperative Day 7. Anastomotic healing was found to be improved in terms of a bursting pressure (P = 0.02). Histopathological examination revealed an increase in angiogenesis (P = 0.007). Moreover, intra-abdominal adhesions were significantly less in rats given sildenafil (P = 0.03). Sildenafil may improve anastomotic healing of the left colon and diminishes peritoneal adhesion formation in the presense of abdominal infection.

Does sildenafil reverse the adverse effects of ischemia on ischemic colon anastomosis: Yes, ‘no’

Introduction Sildenafil may lead an improvement in anastomotic healing of ischemic left colon anastomosis. Methods Thirty-six male Wistar albino rats were randomized into four experimental groups ( n = 9 in each group). In group 1, a well-perfused left colonic segment was transected, and free ends were anatomosed. In groups 2, 3 and 4 animals underwent a standardized surgical procedure to induce ischemic left colon anastomosis. Group 2 animals received only tap water. In groups 3 and 4 animals received 10 mg/kg/body-weight and 20 mg/kg/body-weight sildenafil, single dose a day during 4 days, respectively. Rats were sacrificed on day 4 following operation. Anastomotic integrity, intra-peritoneal adhesion scores, anastomotic bursting pressures and tissue hydroxyproline levels were recorded. Histopathological examination of the anastomosis was also performed. Results There was no statistically significant difference among groups with respect to anastomotic integrity ( p = 0.142) but ischemia decreased the anastomotic bursting pressure. The mean bursting pressure values were 78.8 ± 24.1, 43.3 ± 26, 55.1 ± 32.4, and 43.3 ± 20.4 in groups 1, 2, 3, and 4, respectively. Group 1 had the highest values whereas; there was no statistically significant difference between groups 1 and 3. There was no statistically significant difference among groups 2, 3, and 4 with respect to tissue hydroxyproline levels, adhesion scores and the Chiu scores. The highest inflammatory cell presence in the granulation tissue was detected in group 2, whereas the lowest was detected in group 4 ( p = 0.0001). The highest fibroblast infiltration in the granulation tissue was detected in group 1 ( p = 0.045). Discussion Our results showed that 10 mg/kg sildenafil decreased the adverse effects of ischemia on the healing of ischemic left colon anastomosis. Additional investigations are needed to confirm the effects of phosphodiesterase-5 inhibitors in ischemic colon anastomosis models.

Role of Activated Protein C on Wound Healing Process in Left Colonic Anastomoses in the Presence of Intra‐abdominal Sepsis Induced by Cecal Ligation and Puncture: An Experimental Study in the Rat

Activated protein C (APC) is a serine protease with anticoagulant and anti-inflammatory activities. The delaying effects of intra-abdominal sepsis on wound healing process in colonic anastomoses have been previously demonstrated. This study was designed to investigate the role of APC on wound healing process in left colonic anastomoses in the presence of intra-abdominal sepsis. The left colonic anastomosis was performed in 48 rats that were divided into four groups: (1) sham-operated group, laparatomy plus cecal mobilization (n = 12); (2) sham + APC group, identical to group I except for APC treatment (n = 12); (3) CLP group, cecal ligation and puncture (n = 12); 4) CLP + APC-treated group, 100 microg/kg, 15 min before the construction of colonic anastomosis (n = 12). Anastomotic bursting pressures were measured in vivo on day 7. Tissue samples were obtained for analyses of hydroxyproline (HP) contents, myeloperoxidase (MPO) acivity, malondialdehyde (MDA), and nitrate/nitrite (NO3(-) /NO2(-)) levels. The plasma levels of tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6, and D-dimer also were measured. Intra-abdominal sepsis led to significant decreases in colonic anastomotic bursting pressures and tissue HP contents, along with increases in MPO activity, MDA and NO3(-) /NO2(-) levels, and also plasma levels of TNF-alpha, IL-6, and D-dimer (P < 0.05). However, APC treatment led to significant increases in anastomotic bursting pressures and tissue HP ontents, along with decreases in MPO activity, MDA and NO3(-) /NO2(-) levels, and also plasma levels of TNF-alpha, IL-6, and D-dimer (P < 0.05). This study clearly showed that APC treatment prevented the delaying effects of intra-abdominal sepsis on colonic anastomotic wound healing process. Further clinical studies are required to determine whether APC has a useful role in the enhancement of anastomotic healing during particular surgeries in which sepsis-induced injury occurs.

Effects of Intraperitoneal Sildenafil Administration on Healing of Left Colonic Anastomoses and Intra-Abdominal Adhesion Formation in the Presence of Intra-Abdominal Infection

Purpose The objective of this pilot study was to establish an animal model for intra-abdominal infection and to examine the effect of sildenafil on anastomotic healing of the left colon and intra-abdominal adhesion formation.

Effect of parenteral zinc sulfate on colon anastomosis repair in the rat

To prevent colonic anastomotic dehiscence, pharmaceutical interventions should inhibit degradation of existing submucosal collagen fibers and accelerate the synthesis of new collagen molecules. Zinc has multiple functions in collagen metabolism and was recently found beneficial in colonic anastomosis repair. We have investigated the effect of daily intraperitoneal zinc (2 mg/kg) injections on the development of the biomechanical integrity of left colon anastomoses. Sixty Sprague-Dawley male rats (median 245 g) were allocated to treatment with zinc sulfate in saline (n = 30) or with saline alone (n = 30) starting 1 h before the anastomoses were made. Serum zinc levels and anastomotic breaking strength were determined on postoperative days 3 (n = 30) and 7 (n = 30). The initial breaking strength or suture-binding capacity was determined in additional ten non-treated animals (277 g). The breaking strength of the anastomoses decreased in the two groups combined (n = 30) by 50% (p < 0.001) on day 3 but was regained by postoperative day 7 compared with the initial anastomotic biomechanical strength. Serum zinc levels also increased from day 3 to day 7 in both intervention groups and correlated significantly with breaking strength (r = 0.57, p < 0.001). Although the median serum zinc level was 14% higher (p < 0.01) on day 7 in zinc-treated than in saline-treated animals, the breaking strength did not differ significantly between zinc-treated and saline-treated rats on either day 3 (p = 0.95) or day 7 (p = 0.70). In contrast to previous report in rabbits, we failed to demonstrate the beneficial effects of parenteral zinc supplementation on colon anastomosis repair in a rat model.

Activated protein C prevents deleterious effects of remote reperfusion injury caused by intestinal ischemia on wound healing in the left colonic anastomoses: an experimental study in the murine model

Background Activated protein C (APC) is a serine protease with anticoagulant and antiinflammatory activities. The delaying effects of remote reperfusion injury on the wound-healing process in colonic anastomoses have been previously shown. In this study, we aimed to investigate whether APC protects against deleterious systemic effects of intestinal ischemia/reperfusion (I/R) injury on colonic anastomotic wound healing process. Methods Male Wistar-albino rats were randomly allocated into 4 groups, and a left colonic anastomosis was performed in all animals: (1) sham-operated group, simultaneously with left colonic anastomosis, the superior mesenteric artery and collateral branches were divided from the celiac axis, and the inferior mesenteric artery were isolated but not occluded (group 1, n = 12), (2) sham + APC group, identical to group 1 except for APC treatment (100 μg/kg, intravenously, 15 minutes before construction of the colonic anastomosis), (group 2, n = 12), (3) intestinal I/R group, 60 minutes of superior mesenteric ischemia followed by reperfusion (group 3, n = 12), and (4) APC-treated group, (100 μg/kg, intravenously, 15 minutes before reperfusion) (group 4, n = 12). All animals were sacrificed, and colonic anastomotic bursting pressures were measured in vivo on day 7. Tissue samples were obtained for analysis of hydroxyproline contents, nitrate/nitrite levels, and activities of oxidative and antioxidative enzymes. The plasma levels of proinflammatory cytokines and D-dimer were also measured. Results Intestinal I/R led to significant decreases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with increases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer ( P < .05). However, APC treatment led to significant increases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with decreases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer ( P < .05). Conclusion This study clearly showed that APC treatment prevented the delaying effects of remote I/R injury on colonic anastomotic wound healing process. Further clinical studies are required to determine whether APC has a useful role in the enhancement of colonic anastomotic wound healing after particular operations in which I/R injury occurs.

Sirolimus and intraoperative hyperthermic peritoneal chemoperfusion with mitomycin-C do not impair healing of bowel anastomoses

Surgeons will increasingly have to address the development of gastrointestinal disease in transplant patients or deal with extended bowel resection and bowel anastomosis in advanced cancer patients. Immunosuppressants as well as intraoperative hyperthermic peritoneal chemoperfusion (IHPC) may alter intestinal anastomotic healing. We evaluated the effects of the immunosuppressant sirolimus and of IHPC on healing and stability of bowel anastomoses in pigs. Twenty-four pigs were divided into four groups (SIR: sirolimus was administered orally; IHPC: animals received IHPC with mitomycin-C; COMP: combination of sirolimus and IHPC was administered; CON: sham-treated control group). Animals underwent hand-sutured small bowel and left colon anastomoses and were killed on postoperative day 4. Anastomoses were evaluated by morphometric analysis and immunohistochemistry (IHC) and by measuring the bursting pressure (BP). In all experimental groups (SIR, IHPC, COMP), anastomotic BPs remained unaltered and were not statistically different compared with control (CON). In addition, ileum villous height and colonic crypt depth analysis revealed no significant difference in mucosal thickness, and IHC showed no difference among groups in proliferation, as assessed by the number of KI-67- and bromodeoxyuridine-labeled cells. Immunosuppression with sirolimus as well as IHPC with mitomycin-C do not alter healing of intestinal anastomosis in pigs.

The Effect of Azathioprine on Anastomotic Healing: An Experimental Study in Rats

The cytotoxic and immunosuppressive effects of azathioprine, which mitigate the disease activity in inflammatory bowel disease, may compromise the healing of intestinal anastomoses leading to an increased risk of anastomotic leakage. The effect of azathioprine treatment on intestinal healing was tested. In an experimental study, rats were randomly given one oral dose of azathioprine (5 mg or 20 mg/kg body weight per day) or placebo. After 28 days of treatment, a left colonic anastomosis was performed. After three days of healing, the breaking strengths of the anastomoses were tested, along with measurements of azathioprine major metabolite concentrations: 6-thioguanine and 6-methyl-mercaptopurine. There were no significant differences in the anastomotic breaking strength between the three groups. Daily treatment for four weeks with high or low azathioprine doses has no inhibitory effect on colonic healing in rats.

Icodextrin and Seprafilm® Do Not Interfere with Colonic Anastomosis in Rats

Background: Physical barriers and instilled solutions have been studied to prevent intra-abdominal adhesions. However, undesirable side effects of these substances on the healing of intestinal anastomoses may limit their use. This study was designed to compare the effects of antiadhesives on the healing of colonic anastomosis in rats. Methods: Sixty female Sprague-Dawley rats were divided into 3 groups of 20. The animals received isotonic saline and 7.5% icodextrin, intraperitoneally after standard left colonic anastomosis. In group 3, Seprafilm® was wrapped around the anastomosis and also laid over the abdominal viscera. Half of the animals from each group were killed on postoperative day (POD) 4 and the remaining half on POD 21. Adhesion scoring, bursting pressure and tissue hydroxyproline measurements and histopathological assessment were performed. Results: Mean hydroxyproline levels were significantly higher in groups receiving icodextrin and Seprafilm compared with the control group, whereas mean bursting pressures were significantly higher in the group that received icodextrin (p < 0.05). Intraperitoneal administration of icodextrin resulted in significant reduction of adhesion formation on POD 21 (p < 0.05). Conclusions: Seprafilm does not prevent formation of adhesions as much as icodextrin does, but its effect on the healing of colonic anastomoses is similar.

Effect of Ginkgo biloba Extract (EGb 761) on the Healing of Left Colonic Anastomoses in Rat

The aim of this study was to assess the effect of Ginkgo biloba extract (EGb 761) on healing of experimental colonic anastomoses in a rat model. Rats were divided into four groups: postoperative day (POD) 3 untreated control group, POD 3 EGb 761 group, POD 7 untreated control group, and POD 7 EGb 761 group. In the oral EGb 761 groups, the agent was given at 9.6 mg daily per orogastric route using a 4-F fine feeding catheter. We measured bursting pressures and hydroxyproline content and histologically examined the resected anastomoses on POD 3 and POD 7. The bursting pressures increased more in the EGb 761 group than in the untreated control group on POD 3, but this difference was not statistically significant. Hydroxyproline content was higher in the EGb 761 group than in the untreated control group on POD 3, and this difference was statistically significant. Anastomosis bursting pressure values and hydroxyproline contents were significantly higher in the EGb 761 group than in the untreated control group on POD 7. Histological examination showed greater fibroblastic activity in the EGb 761 group than in the untreated control group on POD 3. There was no significant difference in anastomotic polimorphonuclear leukocyte, mononuclear cells and blood vessel neodevelopment between the POD 3 groups, but there was significant difference in fibroblastic activity and blood vessel neodevelopment between the POD 7 groups. These results showed us that EGb 761 administration resulted in enhanced stability of colonic anastomoses during the first postoperative week.

Pyrrolidine Dithiocarbamate Prevents Deleterious Effects of Remote Ischemia/Reperfusion Injury on Healing of Colonic Anastomoses in Rats

Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-kappaB (NF-kappaB) activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated. In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis in rats. Anastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated group (group I, n = 10)-simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)-identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing the experimental period. (3) I/R group (group III, n = 10)-60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)-PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents, perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level. There was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05). This study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing the safety of the anastomosis during particular operations where remote organ I/R injury occurs.

The effect of erythropoietin on healing of obstructive vs nonobstructive left colonic anastomosis: an experimental study

BackgroundAnastomotic leakage is an important problem following primary resection in the left colon and is even more prominent when obstruction is present. We aimed to evaluate the possible effects of erythropoietin on the healing of anastomosis under both obstructive and non-obstructive states.MethodsForty male Wistar albino rats were divided into four groups. In group I, two cm left colonic resection and primary anastomosis were done. In group II, left colon were completely ligated and 24 hours later animals were re-operated for segmental resection. The same procedures were performed for rats in group III and IV in respect to group I and II and, 500 IU/kg a day erythropoietin were given in the latter two groups for seven days. For the quantative description of anastomotic healing mechanical, biochemical and histopathological parameters were employed on the seventh day and the animals were sacrificied.ResultsAlthough erythropoietin had positive effects on bursting pressure in group IV when compared to group II, it has no effect in group III. Despite the increased tissue hydroxyproline levels in group IV, erythropoietin failed to show any effects in group III.Erythropoietin had positive effects on neovascularization, fibroblast proliferiation and storage of collagen in group IV.ConclusionWe failed to find any direct and evident effects of erythropoietin on healing of left colonic anastomosis. On the other hand, erythropoietin might prevent negative effects of obstruction on healing.

Early glutamine-enriched enteral feeding facilitates colonic anastomosis healing: Light microscopic and immunohistochemical evaluation

Problems related to colonic anastomosis healing constitute the major morbidity in colorectal surgery. Patients without appropriate nutritional support are at higher risk of postsurgical complications, mainly due to reduced wound healing. Therefore, we investigated the effect of early and late postoperative total enteral nutrition (TEN) and glutamine addition on colon anastomosis healing using light microscopy and immunohistochemistry (IGF-I immunolabelling). In this study, 40 Wistar-albino rats underwent distal left colonic transection and anastomosis. The rats were then divided into four groups given different diets: delayed total enteral nutrition (dTEN; beginning 3 days postoperatively), delayed TEN with added glutamine (dTEN+Glutamine), early TEN (eTEN; beginning within 6h postoperatively), and early TEN with added glutamine (eTEN+Glutamine). Colon segments, including the anastomosis, were excised 7 days postoperatively and evaluated histopathologically for inflammation, mucosal healing, submucosal-muscular layer repair, the amounts of necrosis and vascularisation and immunohistochemically for IGF-I labelling. The inflammation and necrosis scores in the dTEN and dTEN+Glutamine groups were significantly greater than in the eTEN and eTEN+Glutamine groups. The IGF-I immunoreactivity increased in the eTEN, eTEN+Glutamine, and dTEN+Glutamine groups compared to dTEN (p<0.05). We concluded that early TEN and glutamine enrichment in the postoperative period improve anastomosis healing via IGF-I.

The Effect of Octreotide on Healing of Injured Colonic Anastomosis with Immediate Postoperative Intraperitoneal Administration of 5-Fluorouracil

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

Tempol prevents harmful effects of remote ischemia reperfusion injury on healing of experimental colonic anastomoses

Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl) is a water-soluble analogue of the spin label TEMPO. As an antioxidative agent, it is a member of nitroxides, which detoxifies superoxide and possibly other toxic radicals in vivo. In this study, we aimed to investigate whether tempol prevents harmful systemic effects of superior mesenteric ischemia-reperfusion on left colonic anastomosis in rats. Anastomosis of the left colon was performed in 30 rats that were divided into three groups each having ten animals: sham-operated control (group I), 60 min of intestinal ischemia-reperfusion by superior mesenteric artery occlusion (group II), and tempol-treated group (30 mg/kg before and after the ischemia-reperfusion (group III). On postoperative day 5, all animals were killed and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for further investigation of anastomotic hydroxyproline content, perianastomotic malondialdehyde, and glutathione levels. There was a statistically significant increase in the quantity of myeloperoxidase activity and malondialdehyde levels in group II, along with a decrease in glutathione levels, anastomotic hydroxyproline content, and bursting pressure values when compared to controls. However, all of the investigated parameters were normalized in tempol-treated animals (group III). We conclude that tempol significantly prevents harmful systemic effects of reperfusion injury on colonic anastomoses in a rat model of superior mesenteric artery occlusion.

Effect of hypercholesterolemia on experimental colonic anastomotic wound healing in rats

To evaluate the mechanical and biochemical parameters of colonic anastomotic healing in hypercholesterolemic rats. Sixty rats were divided into two groups of 30 each according to their dietary regimens. The test group was fed with a high cholesterol-containing diet for two months while the control group had standard diet. These two groups were further divided into three subgroups consisting of ten rats each. After hypercholesterolemia was established, left colon resection and anastomosis were performed in both groups and samples from liver and abdominal aorta were taken to evaluate the systemic effects of hypercholesterolemia. Anastomotic wound healing, blow-out pressures and tissue hydroxyproline levels were evaluated. The test group had a significant weight gain in two months. Microscopic examination of the abdominal aorta revealed no atherosclerotic change in none of the groups, but liver tissue specimens showed significant steatosis in the test group. Tissue hydroxyproline levels and anastomotic blow-out pressures were significantly lower in the test group than in the controls. Hypercholesterolemia not only increases hydroxyproline levels and blow-out pressures but also worsens anastomotic wound healing.

The Effect of Mechanical Bowel Preparation on Colonic Anastomotic Healing: an Experimental Study

Purpose: Although bowel preparation is traditionally used in elective colorectal surgery, its value is debatable. The aim of this study was to evaluate the influence of mechanical bowel preparation on healing of colonic anastomoses.Material and Methods: Twenty-seven rats were divided into three groups, each of nine animals. All rats had left colonic resection and anastomosis. Group 1 and group 2 were the control and sham group, respectively. Group 3 had colonic lavage before resection and anastomosis. On the fourth postoperative day, animals were killed; bursting pressure and tissue hydroxyproline concentrations were measured and compared.Results: The median bursting pressure values were 87 (range 4–135) mmHg in group 1, 88 (range 78–136) mmHg in group 2 and 76.0 (range 57.0-125) mmHg in group 3. The differences between bursting pressure values of the groups were not statistically significant (p= 0.07). The median tissue hydroxyproline concentrations were 3.25 (range 2.635.16) mg/mg in group 1, 4.15 (range 1.54-5.72) mg/mg in group 2 and 3.52 (range 2.04-5.27) mg/mg in group 3. The differences between tissue hydroxyproline concentrations of the groups were not statistically significant (p = 0.7). Conclusion: Mechanical bowel preparation is not necessary for enhancing colonic anastomotic integrity in the rat.