Effect of antibiotics in fibrin sealant on healing colonic anastomoses in the rat.

In 90 rats a colonic anastomosis was constructed with 12 interrupted 7/0 polypropylene sutures. Group 1 (n = 30) served as a control group. In group 2 (n = 30) the anastomosis was sealed with fibrin adhesive and in group 3 (n = 30) a mixture of fibrin, clindamycin and cefotaxime was used. On days 2, 4 and 7, ten animals in each group were killed. Adhesion formation was significantly increased in groups 2 and 3 compared with the control group. On day 2 the anastomosis was significantly stronger after sealing with antibiotic-fibrin mixture. On day 4 the bursting pressure in group 2 was significantly lower than in groups 1 and 3. At the same time the concentration of hydroxyproline was significantly reduced in group 2, but not in group 3. The addition of antibiotics prevents the negative effect of fibrin adhesive on the healing colonic anastomosis and contributes to a stronger anastomosis on day 2 after operation.     

Adverse influence of fibrin sealant on the healing of high-risk sutured colonic anastomoses.

The effect of fibrin glue sealing on sutured colonic anastomoses was studied using a 'high-risk' colon anastomosis model in the rat. Animals (n = 104) were randomized to have their sutured anastomosis sealed with fibrin glue or left untreated. They were assessed clinically until they were killed on the fourth day after surgery when contrast radiology, detailed post-mortem examination, anastomotic bursting pressure (ABP) and assessment of adhesion formation were performed. The clinical outcome was worse in the glued group (toxic or death from sepsis: 18 versus seven in the non-glued group; P = 0.0354), which also showed a significantly higher moderate to major leak rate (17 versus two in the non-glued group; P = 0.0009). The median ABP was significantly higher in the glued anastomosis group (96 versus 68 cmH2O in the non-glued group; P = 0.0367). Excessive perianastomotic adhesion formation was significantly greater in the glued group. Microscopic examination showed an extremely intense inflammatory reaction in the glued anastomoses compared with that in the untreated group. These results indicate that sealing of a sutured anastomosis with fibrin glue containing an antiproteinase impairs healing the of anastomotic wound, probably by resisting the ingrowth of vascular granulation tissue during the early stages of repair.     

Effect of melatonin on healing of colonic anastomosis in a rat model of peritonitis

BACKGROUND: The aim of this study is to determine the effect of melatonin on intestinal anastomosis in the presence of peritonitis. MATERIAL AND METHODS: 32 Wistar albino rats were randomized into four groups (n = 8): A (sham), B (control), C (melatonin 5 mg/kg), and D (melatonin 10 mg/kg). In group A, only cecal dissection was carried out. In the other groups, cecal ligation and puncture (CLP) followed cecal dissection in order to induce bacterial peritonitis. 24 h after the previous operation, cecal resection and ileocolic anastomosis were performed in the rats of all groups. In group C (5 mg/kg) and group D (10 mg/kg), melatonin was injected for 5 consecutive days starting after CLP. At the 48th hour of the CLP procedure, blood was drawn via the tail vein for tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) analysis, and on the 4th day of the experiment relaparotomy was carried out for bursting pressure (BP) measurements. The intestinal tissue containing the anastomotic line was then snap-frozen in liquid nitrogen and stored at -80 degrees C for determination of tissue levels of malondialdehyde (MDA) and glutathione (GSH). RESULTS: The tissue MDA level, blood TNF-alpha and IL-6 levels of group B were significantly higher than in the other groups, whereas the BP results and GSH levels of group B were found to be significantly lower than in the other groups. The results of groups C and D are statistically different from those of group B. When we compared the results of groups C and D, we found significantly higher results in terms of BP and GSH levels in group D and also significantly lower results in terms of MDA, blood TNF-alpha and IL-6 levels in group D. CONCLUSION: The findings of this experiment suggest that melatonin has a dose-independent positive effect on wound healing of colonic anastomosis.     

Effect of fibrin sealant on the tensile strength of rat visceral pleura

Post mortem studies of rat lungs showed that application of fibrin sealant augments the tensile strength of the lung/visceral pleura by approximately 100 mmHg, thus impeding air leakage.     

The effect of fibrin sealant on the healing of laser-resurfaced skin

Background: Fibrin sealant is an effective hemostatic agent and a useful tissue sealant. Studies have also suggested that fibrin sealant may accelerate the normal wound-healing process. Objective: This study was designed to ascertain whether fibrin sealant would enhance wound healing after CO₂ laser resurfacing in a guinea pig model. Methods: The CO₂ laser was used to create equal areas of skin resurfacing on both sides of 14 Dunkin Hartley guinea pigs. Fibrin sealant was applied to the treatment side, whereas bacitracin was applied to the control side. Biopsies of these areas were performed on days 1, 3, 7, and 10. A histologic evaluation was performed with the use of a grading scale that compared acute and chronic inflammation, granulation tissue, collagen deposition, and epidermal regeneration. Results: The wounds treated with fibrin sealant demonstrated a statistically significant reduction in the degree of acute and chronic inflammation as well as collagen deposition. At day 7, fibrin sealant was noted to enhance neovascularization and result in a slight delay in reepithelialization. All wounds were completely reepithelialized at day 10. No wound infections or other complications were noted as a result of the application of fibrin sealant. Conclusions: Although wound healing was not accelerated, the application of fibrin sealant after CO₂ laser resurfacing diminished the acute and chronic inflammatory response, enhanced neovascularization, and reduced collagen accumulation. Further research is needed to assess whether the effects of fibrin sealant noted in this study result in improved cosmetic healing after CO₂ laser resurfacing. (Aesthetic Surg J 2001;21:509-517.)     

Effect of nutritional route on colonic anastomotic healing in the rat

Although early enteral feeding has been shown to benefit cutaneous healing when compared to parenteral feeding, the effect of the route of nutritional support in gastrointestinal anastomotic healing has not been defined. The aim of the present study was to determine whether the route of nutritional support influences colonic anastomotic healing. Twenty male Sprague-Dawley rats weighing 270 to 290 grams underwent identical surgical manipulation consisting of central venous catheterization, gastrostomy insertion, and distal colonic anastomosis (single-layer, inverted). Identical nutrient infusates composed of 4.25% amino acids, 25% dextrose, and vitamins were administered, with half the animals receiving the infusions via the gastrostomy and the other half via the venous catheter. Animals were killed 5 days after surgery. There were no differences in nutritional parameters between the parenterally and enterally fed groups. Colonic anastomotic bursting pressure was significantly higher in the enterally fed group (180 ±6 vs. 150±11 mm Hg; P<0.01). The measured insoluble collagen and total protein content in anastootic tissue were enhanced in the enterally supported group. The fraction of soluble (newly synthesized) collagen did not differ between the two groups. The data demonstrate that the route of nutrient administration influences colonic anastomotic healing. The preservation of colonic structural collagen in the enteral group may improve the ability of the gut to hold sutures and thus enhance anastomotic healing. Presented at the Thirty-Ninth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, La., May 17–20, 1998.     

Effects of intraluminal infusion of short-chain fatty acids on the healing of colonic anastomosis in the rat

The effects of an intracolonic infusion of short-chain fatty acids (SCFA) on the healing of colonic anastomosis in the rat were investigated. Thirty-three Sprague-Dawley rats underwent transection and anastomosis of the descending colon and transection and diversion of the ascending colon. The proximal limb of the ascending colon was exteriorized as an end colostomy, and the distal (defunctionalized) limb was cannulated for continuous infusion. Rats received either no infusion (N = 11) or an infusion of either electrolytes (N = 11) or SCFA (acetate, propionate, and butyrate; N = 11) into the defunctionalized colonic segment. On the sixth postoperative day bursting pressure (BP) and bowel wall tension (BWT) were determined. The occurrence of spontaneous anastomotic dehiscence was significantly less for the SCFA group (0/11) compared with the no infusion group (5/11, p less than 0.01). The anastomotic suture line burst in significantly fewer colons from the SCFA group (1/11) than either the electrolyte infusion (8/11, p less than 0.003) or the no infusion (6/6, p less than 0.001) groups. BP and BWT were significantly higher for the SCFA group (BP: 147 +/- 10 mm Hg; BWT: 59 +/- 1.0 dyne 10(3)/cm) than for either the electrolyte (BP: 99 +/- 30 mm Hg, p less than 0.002; BWT: 45 +/- 19, p less than 0.03) or no infusion (BP: 111 +/- 42, p less than 0.02; BWT 36 +/- 15, p less than 0.007) groups. The results of this study indicate that intracolonic infusion of SCFA resulted in significantly stronger colonic anastomosis in the rat.     

The effect of Bosentan on healing of colonic anastomosis

Background  

Ischemia is the most important factor compromises wound healing in colonic anastomosis. Mesenteric vessels are ligated at first while performing colonic resection and following anastomosis. Therefore blood supply of the related segments of colon temporarily interrupted and ischemia can easily occur. This study was carried out to explore whether Bosentan, an endothelin-receptor antagonist, can eliminate vasoconstruction, increase blood flow in the splanchnic area and anastomotic region and therefore possibly facilitate wound healing and prevent intra-abdominal adhesion formation.     

Myofibroblasts and colonic anastomosis healing in Wistar rats

Background  

The myofibroblasts play a central role in wound healing throughout the body. The process of wound healing in the colon was evaluated with emphasis on the role of myofibroblasts.     

Myofibroblasts and colonic anastomosis healing in Wistar rats

Background

Mesh repair of incisional hernia is superior to the conventional technique. From all available materials for open surgery polypropylene (PP) is the most widely used. Development resulted in meshes with larger pore size, decreased mesh surface and lower weight. The aim of this retrospective non randomized study was to compare the quality of life in the long term follow up (> 72 month) after incisional hernia repair with "light weight"(LW) and "heavy weight"(HW) PP meshes.

Methods

12 patients who underwent midline open incisional hernia repair with a HW-PP mesh (Prolene^® 109 g/m² pore size 1.6 mm) between January 1996 and December 1997 were compared with 12 consecutive patients who underwent the same procedure with a LW-PP mesh (Vypro^® 54 g/m², pore size 4-5 mm) from January 1998. The standard technique was the sublay mesh-plasty with the retromuscular positioning of the mesh. The two groups were equal in BMI, age, gender and hernia size. Patients were routinely seen back in the clinic.

Results

In the long term run (mean follow up 112 ± 22 months) patients of the HW mesh group revealed no significant difference in the SF-36 Health Survey domains compared to the LW group (mean follow up 75 ± 16 months).

Conclusions

In this study the health related quality of life based on the SF 36 survey after open incisional hernia repair with light or heavy weight meshes is not related to the mesh type in the long term follow up.     

Thrombogenic effects of a nonthrombin-based fibrin sealant compared with thrombin-based fibrin sealant on microvenous anastomoses in a rat model

The efficacy and safety of tissue adhesives needs to be clearly defined. A thrombin-based preparation of fibrin sealant has recently been shown to have deleterious effects on microvascular anastomoses in an animal model. The authors found that fibrin sealant constructed with a high concentration of bovine thrombin (1,000 IU per milliliter) was detrimental to microvascular patency when applied to the anastomosis in a rat free flap model. The microvenous anastomosis had the highest rate of thrombosis and failure in this model. A nonthrombin-based fibrin sealant has recently become available for experimental investigation. This study examined the thrombogenic effect of this nonthrombin-based fibrin sealant on microvenous anastomoses in a rat free flap model compared with the effect of traditionally prepared fibrin sealant with varying concentrations of thrombin. The conclusions reveal that flap survival with application of the nonthrombin-based fibrin sealant to the anastomosis was comparable with flap survival of the control animals. Flap survival with application of the traditionally prepared thrombin-based fibrin sealant was also comparable with flap survival of the control animals when a concentration of 500 IU per milliliter of thrombin was used. However, flap survival decreased significantly (p <0.005) when a concentration of 1,000 IU per milliliter of thrombin was used in the construct of the fibrin adhesive. These results support the previous findings of the harmful effects of thrombin when used in high concentrations and applied to the microvenous anastomosis of this free flap model. Moreover, this initial investigation with a nonthrombin-based fibrin sealant did not show any deleterious effects on the microvenous anastomosis compared with control animals.     

Effect of hyperbaric oxygen on microvascular anastomosis healing and patency in the rat

Recent evidence has shown that changes in blood viscosity and marked increases in both platelet count and fibrinogen concentration occur after exposure to hyperbaric oxygen (HBO). The purpose of the present study was to address whether repeated HBO therapy would increase either hematocrit or platelet count, and to determine if these changes would influence the patency of the microvascular anastomosis, as well as anastomotic healing. Eighty femoral arteries from 40 rats were divided into four groups (n = 10), and arterial anastomoses were performed on normal arteries in the first two groups, and on crushed arteries in the second two groups. One of the normal artery groups and one of the crushed artery groups received repeated HBO treatments for 5 days. Anastomotic patency rates, platelet count, hematocrit, and breaking strength were recorded. Among the results of this study were that: (1) there was no difference in patency rate following HBO treatment in both the normal and crushed artery groups; (2) platelet count was significantly higher following HBO treatment in the groups with the undamaged arteries; (3) breaking strength was significantly increased following HBO treatment in the groups with the crushed arteries. The authors concluded that HBO therapy may be useful in improving the healing of microvascular anastomoses in vessels that have undergone crush injury. Although HBO treatment results in an increased platelet count, this does not influence anastomotic patency.     

Effect of recombinant human granulocyte/macrophage colony-stimulating factor on the healing of colonic anastomosis in rats.

The purpose of this study was to investigate the efficacy of recombinant human granulocyte/macrophage colony-stimulating factor (rHuGM-CSF) on the wound healing of colonic anastomosis in rats. In total, 40 male Wistar rats were taken into this study. The control group (n = 20) received subcutaneous saline injection. The experiment group (n = 20) received rHuGM-CSF at 100 microg/kg subcutaneously. Both groups underwent colonic anastomosis 2 days later. In each group, burst pressure and hydroxyproline levels were determined 3 and 7 days after anastomosis. White blood cell (WBC) and red blood cell (RBC) counts were determined in each group to evaluate the effect of rHuGM-CSF on hematologic parameters in rats. There was no significant difference between the two groups in regard to burst pressure and hydroxyproline levels (p > .05). As expected, WBC counts significantly increased in the experiment group on days 3 (p = .035) and 7 (p = .046) following surgery. In conclusion, rHuGM-CSF administration and increased WBC counts did not have any positive effect on the wound healing of colonic anastomosis.     

Hydroxyethyl starch 130/0.4 augments healing of colonic anastomosis in a rat model of peritonitis

Background

This study was designed to investigate the role of hydroxyethyl starch (HES) 130/0.4 on the wound healing process in left colonic anastomoses in the presence of intra-abdominal sepsis.

Methods

The left colonic anastomosis was performed in 40 rats that were divided into 4 groups: (1) group SHAM, laparatomy plus cecal mobilization (n = 10); (2) group SHAM + HES, HES130/.4-treated controls (n = 10); and (3) group CLP, cecal ligation and puncture (n = 10); (4) group CLP + HES, CLP plus HES130/.4 (n = 10). HES130/.4 was administrated before the construction of colonic anastomosis, 15 mL/kg/24 hours and daily for 4 postoperative days. Anastomotic bursting pressures (ABPs) were measured in vivo on day 5. Tissue samples were obtained for analyses of hydroxyproline (HP) contents, myeloperoxidase (MPO) activity, malondialdehyde (MDA), reduced glutathione (GSH) levels, and nuclear factor-κB (NF-κB) activation. The plasma levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, d-dimer, and protein C (PC) were also measured. Anastomotic granulation tissues were fixed for transmission electron microscopic (TEM) analyses.

Results

Intra-abdominal sepsis led to significant decreases in colonic anastomotic bursting pressures, perianastomotic tissue HP contents, GSH levels, and plasma levels of PC, along with increases in perianastomotic tissue MPO activity, MDA levels, NF-κB activation, and plasma levels of TNF-α, IL-6, and d-dimer. However, HES130/.4 treatment significantly inhibited all these responses. TEM analyses revealed that there was a trend toward a higher density of fibroblast distribution and a higher rate of fibroblast activation in the SHAM- and HES 130/0.4-treated animals, compared with the CLP group.

Conclusions

This study showed that moderate doses (15 mL/kg) of HES 130/0.4 administration significantly prevented this intraperitoneal sepsis-induced impaired anastomotic healing of the left colon. This beneficial effect of HES 130/0.4 can be mainly attributed to its anti-inflammatory and antioxidant properties and beneficial effects of modulating endothelial-associated coagulopathy.     

The hemodynamic behavior of arterial anastomosis using fibrin sealant: experimental study in swine

The wide use of biological sealants as a reinforcement for arterial sutures and the small experimental base in literature motivated this study. Our aim was to evaluate the flow, tear pressure, and the need of reinforcement stitches in sutured arteries after a cross-section. This research project complied with the Helsinki convention. The Tissucol (Baxter) fibrin sealant was used in all experiments. The femoral and carotid arteries of 17 swine from the same breed (weighing from 15 to 20 kg) were cross-sectioned after heparinization and subjected to anastomoses using a single continuous plane of 7-0 prolene. We worked with 68 artery samples, 34 in the treatment group and 34 in the control group. For each animal, one carotid and one femoral artery randomly received fibrin sealant with the contralateral side being used as a control. The need and the number of reinforcement stitches were recorded. Ten minutes after protamine infusion, the animals were sacrificed and the arteries were catheterized respecting 1 cm proximal and distal. The arteries were measured and placed on a flow meter to evaluate the flow rate of 10 mL of 0.9% NaCl in a 50 cm high column. The arteries were then subjected to air infusion at increasingly higher pressures (stepwise increases of 25 mm Hg), the grafts were dipped in 0.9% NaCl solution, the first air leakage was observed, and the tear pressure recorded. Data was analyzed with EpiInfo 6 data manager. The external diameters and thickness of the arteries were similar in both the treatment and control group. There was no significant difference between the groups regarding the tear pressure (P = 0.329), flow rate (P = 0.943), and the number of samples with a tear pressure above 200 mm Hg. However, the sealant reduced the number of reinforcement stitches necessary (P = 0.029). We conclude that fibrin sealant reduces the need of additional stitches; however, it does not change the tear pressure nor significantly reduces the flow.     

Effect of compression with aerosolized fibrin sealant on surgical hemostasis

In order to decrease complications following incomplete hemostasis after surgery, especially in the case of arterial bleeding, we experimentally investigated an effective way of applying fibrin glue as a sealant. Using white rabbits as a model, in which arterial bleeding from the abdominal aorta was induced, fibrin glue and a related hemostatic agent were tested to evaluate the hemostatic effectiveness. Group I (n = 9): Fibrin glue was applied by spraying it on the fingertip and then placing the fingertip on the bleeding part and pressing. Group II (n = 9): Fibrin glue was applied with oxycellulose on the fingertip and then placing the fingertip on the bleeding part and pressing. The results demonstrated that: 1) Although complete hemostasis could not be obtained with finger-pressing alone in 30 second, it could be obtained in 9/9 cases 100%) in Group I but in only 3/9 cases (33%) in Group II. 2) Pressure-resistant force was higher for Group I at an earlier time after hemostasis (p < 0.05). 3) Pathological study reconfirmed the predominance of Group I. We conclude from this study that ideal hemostasis can be obtained with fibrin glue applied simply by spraying it on the fingertip and then placing the fingertip on the bleeding part and pressing.     

Influence of the stable prostacyclin analog iloprost on the healing of colonic anastomosis in rats

AIM: The aim of this study was to investigate whether iloprost injected intraperitoneally immediately after colon resection can improve anastomotic healing on the fifth and eighth postoperative days. METHODS: Forty Wistar rats were randomised into 2 equal groups. After the resection of a 1 cm segment of transverse colon, an end to end sutured anastomosis was generated. From the day of the operation, group 1 (control) received intraperitoneal 3 cc saline solution once daily until sacrifice, while group 2 (iloprost) received iloprost in a dose of 2 mg/kg body weight intraperitoneally once daily until sacrifice. Each group was further randomly divided into 2 equal subgroups and animals were sacrificed on the fifth (subgroup A), and eighth (subgroup B) postoperative days. After sacrifice, anastomoses were examined macroscopically and were measured for bursting pressures and tissue hydroxyproline levels while anastomotic healing process was evaluated histopathologically. RESULTS: None of the rats exhibited any clinical evidence of leakage and there were no instances of peri-anastomotic abscess or peritonitis. Bursting pressure on the fifth postoperative day was significantly higher in the iloprost group than in the control group (P<0.001), while on the eighth postoperative day, bursting pressure was higher in the iloprost group but not significantly different (P=0.165). On both the fifth and eighth postoperative days rats in the iloprost group developed significantly more marked neo-angiogenesis and, in parallel with this, there was a trend showing a higher inflammatory cell infiltration. CONCLUSION: The intraperitoneal administration of iloprost promoted neo-angiogenesis and enhanced colonic healing on the fifth postoperative day.     

Evaluation of a fibrin sealant free of bovine-derived components in an experimental vas anastomosis study

OBJECTIVES: The risk of transmission of bovine spongiform encephalopathy cannot be excluded from the use of bovine-derived products. The present study was undertaken to evaluate the performance of a new fibrin glue free of bovine-derived components in vas anastomosis and to compare this product to conventional vas anastomosis with fibrin glue. METHODS: Bilateral delayed vas anastomosis was performed in 40 Sprague-Dawley rats. All animals underwent a fibrin glue-assisted vas anastomosis with three transmural sutures tied prior to fibrin glue application. The composition and preparation of fibrin glue was similar for all vas anastomoses except the fibrinolysis inhibitor component which was aprotinin (3,000 KUI/ml) in group 1 and tranexamic acid (10 mg/ml) in group 2. The animals (20 rats in both groups) were sacrificed 7 weeks postoperatively and evaluated for gross patency, presence of sperm granuloma and tensile strength measurements at the anastomosis site. RESULTS: No difference was found between the 2 groups for all parameters evaluated whether a bovine-derived or a synthetic fibrinolysis inhibitor component was used. CONCLUSION: This study showed that tranexamic acid, a fibrinolysis inhibitor, can be substituted for conventional fibrin glue thereby avoiding the risks of bovine products.     

Mechanical strength in rat skin incisional wounds treated with fibrin sealant

The biomechanical strength of skin incisional wounds of rats treated with fibrin sealant was assessed by in vitro determination of maximum tensile strength and relative failure energy. Wounds adapted without application of fibrin sealant served as control. Both types of wounds were fixed with surgical tape for the first 8 days of healing. Measurements were performed after 0, 2, 4, 8, 20, and 42 days of healing. After 2 days of healing, wounds treated with fibrin sealant possessed increased maximum tensile strength and relative failure energy. This increase corresponds to the initial strength of the fibrin sealed wounds (0 day values). After 4 and 8 days of healing, no differences were found between the sealed and unsealed groups. After 20 days, the pattern had changed showing increased tensile strength and relative failure energy in wounds not treated with fibrin sealant. A similar trend was reported after 42 days of healing. In both sealed and control wounds, an increase in strain at maximum stress during healing was most pronounced in the first 8 days. After 2 days of healing the strain at maximum stress was increased in wounds treated with fibrin sealant.