Healing of colon anastomoses covered with fibrin glue after immediate postoperative intraperitoneal administration of 5-fluorouracil

Thromboelastometric Analysis of Anticancer Cerrena unicolor Subfractions Reveal Their Potential as Fibrin Glue Drug Carrier Enhancers

In this study, the influence of two subfractions (with previously proven anti-cancer properties) isolated from wood rot fungus Cerrena unicolor on the formation of a fibrin clot was investigated in the context of potential use as fibrin glue and sealant enhancers and potential wound healing agents. With the use of ROTEM thromboelastometry, we demonstrated that, in the presence of fibrinogen and thrombin, the S6 fraction accelerated the formation of a fibrin clot, had a positive effect on its elasticity modulus, and enhanced the degree of fibrin cross-linking. The S5 fraction alone showed no influence on the fibrin coagulation process; however, in the presence of fibrin, it exhibited a decrease in anti-proliferative properties against the HT-29 line, while it increased the proliferation of cells in general at a concentration of 100 µg/mL. Both fractions retained their proapoptotic properties to a lesser degree. In combination with the S6 fraction in the ratio of 1:1 and 1:3, the fractions contributed to increased inhibition of the activity of matrix metalloproteinases (MMPs). This may suggest anti-metastatic activity of the combined fractions. In conclusion, the potential of the fractions isolated from the C. unicolor secretome to be used as a means of improving the wound healing process was presented. The potential for delivering agents with cytostatic properties introduced far from the site of action or exerting a pro-proliferative effect at the wound site with the aid of a fibrin sealant was demonstrated.

Effect of platelet-rich plasma on colon anastomosis in rats in which hyperthermic intra-peritoneal chemotherapy was performed using 5-fluorouracil

BACKGROUND

Hyperthermic intra-peritoneal chemotherapy (HIPEC) performed in patients with peritoneal carcinomatosis has a cytotoxic effect on tumour cells. This cytotoxic effect also adversely affects the wound healing of anastomosis, which is frequently undertaken in this patient group, and causes anastomotic leakage and intestinal fistulas. Platelet-rich plasma (PRP) gel has been used in wound healing and has shown efficacy. We investigated the effect of PRP gel on colon anastomosis healing in rats treated with 5-fluorouracil (5-FU).

METHODS

Twenty-four rats were divided into three groups, each containing eight rats: group 1 (control) underwent colon anastomosis alone; group 2 (5-FU) underwent a colon anastomosis and HIPEC; and group 3 (5-FU + PRP) underwent a colon anastomosis and HIPEC and received topical PRP gel. The rats were sacrificed on the post-operative day 7 and the anastomotic bursting pressure (ABP) was measured. Tissue samples were obtained to measure the hydroxyproline level and investigate the histopathological changes on the anastomosis line.

RESULTS

ABP was higher in the control and 5-FU + PRP groups than in the 5-FU group (P = 0.009, P = 0.047). The tissue hydroxyproline levels were higher in the control and 5-FU + PRP groups than in the 5-FU group (P = 0.001, P = 0.030). The histopathological findings of the 5-FU + PRP group were better than those of the 5-FU group.

CONCLUSION

This study showed that the application of PRP gel to colon anastomoses increased ABP in rats treated with HIPEC using 5-FU. It also showed positive effects on anastomotic healing by increasing the tissue hydroxyproline levels on the anastomosis line and reducing the inflammatory response.

Effect of Paclitaxel-based Hyperthermic Intraperitoneal Chemotherapy (HIPEC) on colonic anastomosis in a rat model

BACKGROUND

Paclitaxel has been used frequently for Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for ovarian carcinomatosis. Cytoreductive surgery and HIPEC are associated with high rates of morbidity being anastomotic dehiscence one of the most frequent. The objective of this study is to quantify the effect of Paclitaxel-based HIPEC on colonic anastomosis in an experimental rat model.

METHODS

After left colon resection and anastomosis, animals were randomized into four groups: Controls (C); Hyperthermia (H); Normothermic Intraperitoneal Paclitaxel (CP) and Paclitaxel-based HIPEC (HP). On postoperative day four, animals' peritoneal cavities were examined macroscopically, colon anastomosis burst pressures measured and specimens analyzed histologically.

RESULTS

Thirty-nine animals were randomized and 36 were included in the analysis. H group presented the highest burst pressure 105.11 ± 22.9 mmHg, which was 27% higher than C (77.89 ± 27.6 mmHg). On the other hand, HP presented the lowest burst pressure 64 ± 26 mmHg, 16% lower than C group and 39% lower than H, being this latter difference statistically significant (p = 0.004). There were no significant differences regarding weight loss, adhesion scores, perianastomotic abscesses and histological findings (inflammation, fibroblasts, neoangiogenesis, and collagen among groups).

CONCLUSION

Strength of colonic anastomosis was improved by isolated hyperthermia and negatively affected by Paclitaxel-based HIPEC.

Comparison of effects of the tacrolimus and cyclosporine A on the colon anastomosis recovery of rats

Purpose

This study aims to examine and compare the effects of immunosuppressant cyclosporine A (CsA) and tacrolimus (TAC) on colon anastomosis recovery.

Methods

Forty rats were randomly divided into 4 groups. The 4 groups were determined as follows: control group; sham group, given %0.09 NaCl; TAC group, given 0.5 mg/kg/day tacrolimus; and CsA group, given 5 mg/kg/day CsA. A 6-cm midabdomen incision was performed on the rats. An incision of all layers on the right colon was performed. Then anastomosis was undertaken. Laparotomy was performed on the seventh day postoperation. The colon bursting pressures were evaluated, histopathological examinations were undertaken, and E-cadherin expression and tissue hydroxyproline levels were evaluated.

Results

Statistically significant differences were observed among bursting pressures of the groups (P < 0.001). The value was significantly low in TAC and CsA groups when compared to control and sham groups (P < 0.05). The tissue hydroxyproline levels were significantly low in TAC group compared to control group (P = 0.03). Fibroblast density and neovascularization were significantly greater in the control group compared to the TAC group (P < 0.05). Levels of collagen had decreased significantly in TAC group compared to other groups (P < 0.05).

Conclusion

Our study showed that TAC may have a negative effect of colon anastomosis recovery. The lowest anastomosis bursting pressure was detected in TAC group. Also, collagen, hydroxyproline, fibroblast, neovascularization and E-Cadherin levels were comparatively lower in TAC group. CsA did not cause any significant changes to tissue hydroxyproline, collagen, fibroblast, and E-Cadherin levels.

International consensus statement regarding the use of animal models for research on anastomoses in the lower gastrointestinal tract

PURPOSE

This project aimed to reach consensus on the most appropriate animal models and outcome measures in research on anastomoses in the lower gastrointestinal tract (GIT). The physiology of anastomotic healing remains an important research topic in gastrointestinal surgery. Recent results from experimental studies are limited with regard to comparability and clinical translation.

METHODS

PubMed and EMBASE were searched for experimental studies investigating anastomotic healing in the lower GIT published between January 1, 2000 and December 31, 2014 to assess currently used models. All corresponding authors were invited for a Delphi-based analysis that consisted of two online survey rounds followed by a final online recommendation survey to reach consensus on the discussed topics.

RESULTS

Two hundred seventy-seven original articles were retrieved and 167 articles were included in the systematic review. Mice, rats, rabbits, pigs, and dogs are currently being used as animal models, with a large variety in surgical techniques and outcome measures. Forty-four corresponding authors participated in the Delphi analysis. In the first two rounds, 39/44 and 35/39 participants completed the survey. In the final meeting, 35 experts reached consensus on 76/122 items in six categories. Mouse, rat, and pig are considered appropriate animal models; rabbit and dog should be abandoned in research regarding bowel anastomoses. ARRIVE guidelines should be followed more strictly.

CONCLUSIONS

Consensus was reached on several recommendations for the use of animal models and outcome measurements in research on anastomoses of the lower GIT. Future research should take these suggestions into account to facilitate comparison and clinical translation of results.

Fibrin glue does not improve healing of gastrointestinal anastomoses: a systematic review

BACKGROUND/AIM

Anastomotic leakage remains a frequent and serious complication in gastrointestinal surgery. In order to reduce its incidence, several clinical and experimental studies on anastomotic sealing have been performed. In a number of these studies, the sealing material has been fibrin glue (FG), and the results in individual studies have been varying. The positive effect of anastomotic sealing with FG might be due to the mechanical/physical properties, the increased healing of the anastomoses or both. The aim of this systematic review was to evaluate the existing evidence on the healing effects of FG on gastrointestinal anastomoses.

METHODS

PubMed, EMBASE and the Cochrane databases were searched for studies evaluating the healing process of gastrointestinal anastomoses after any kind of FG application. The search period was from 1953 to December 2013.

RESULTS

Twenty-eight studies were included in the qualitative synthesis. These studies were all experimental studies, since no human studies used histological or biochemical evaluation of healing. In 7 of the 28 studies, a positive effect of FG on healing was found, while 8 studies reported a negative effect and 11 studies found no effect. Furthermore, 2 studies reported unclear results. The difference in the study outcome was independent of the study design and the type of FG used.

CONCLUSION

In the available studies, FG did not consistently have a positive influence on the healing of gastrointestinal anastomoses. It is consequently plausible that the positive effect of FG sealing of gastrointestinal anastomoses, if there is any, may be due to a mechanical sealing effect rather than due to improved healing per se.

Effects of TachoSil and 5-fluorouracil on colonic anastomotic healing

BACKGROUND

The administration of intraperitoneal (IP) 5-fluorouracil (5-FU) during the early postoperative period after cytoreductive surgery can decrease local cancer recurrence but may also cause impairment of the anastomotic healing. This study examined the effects of the use of this therapy and of the anastomotic sealing with TachoSil, a fibrin-thrombin coated sealant (FTCS), on the healing of colon anastomoses.

MATERIALS AND METHODS

Forty male rats were divided into four groups (1-4, 10 rats each) that underwent transection and anastomosis of the left colon. The anastomoses were covered with FTCS in groups 2 and 4. Saline solution (2 mL/d-groups 1 and 2) or 5-FU (20 mg/kg/d; groups 3 and 4) was administered IP once daily for 3 d. Bursting pressure (BP) was recorded, and the anastomoses were examined macroscopically and graded histologically.

RESULTS

The relative weight loss was significantly higher in group 3 than in the other groups (P = 0.0004). Anastomotic dehiscence, postoperative adhesion formation, perianastomotic collections, and preanastomotic dilatation did not differ significantly among groups. BP was significantly lower in group 3 compared with all other groups (P = 0.001). Neoangiogenesis was significantly lower in group 3 compared with groups 1 and 2 (P = 0.05). Fibroblastic activity was significantly higher in group 1 compared with group 3 (P = 0.035). Inflammatory cell infiltration and collagen deposition did not differ significantly among groups.

CONCLUSIONS

Our results shown that the early postoperative IP chemotherapy with 5-FU impaired the healing of colon anastomoses. However, anastomotic sealing with FTCS reversed some of the negative effects of this therapy.

The use of collagen content as determined by spectral domain polarization-sensitive optical coherence tomography to assess colon anastomosis healing in a rat model

BACKGROUND/PURPOSE

Many studies have been undertaken to prevent anastomosis leakage of the colon, and several methods have been used to assess anastomosis healing, such as measurement of bursting pressure or hydroxyproline (a marker of collagen) content at the anastomosis site. However, these methods are inappropriate for comparing anastomosis healing at two time points in the same animals. In the present study, we measured the collagen level by spectral domain polarization-sensitive optical coherence tomography (SD-PS-OCT) to assess anastomosis healing.

METHODS

Sprague-Dawley rats were divided into groups C (saline-administered controls; study group) and M [a 5-fluorouracil (5-FU)-administered experimental group]. Immediately after end-to-end anastomosis of the colon, SD-PS-OCT images of anastomoses were taken (baseline). Animals were administered saline or 5-FU for 7 days. On the 7th postoperative day, SD-PS-OCT images were acquired, a histopathologic exam was performed, and hydroxyproline levels as well as mRNA expressions of collagen-1 and collagen-3 were measured at the anastomosis site.

RESULTS

Fibroblast proliferation and inflammatory cell infiltration were greater in group C than in group M. The mRNA expressions of collagen-1 and collagen-3 were substantially higher in group C. Hydroxyproline levels were higher in group M than in group C. Though collagen levels measured by SD-PS-OCT at 7 days were elevated compared with baseline in group C, no such changes were observed for group M.

CONCLUSION

Collagen levels at the colon anastomosis site, measured with SD-PS-OCT, were not increased at 7 days postoperatively versus baseline when 5-FU was injected, but were increased in saline-treated controls. The measurement of collagen content by SD-PS-OCT was found to provide a good means of assessing anastomosis healing, because it allows in situ assessment of collagen contents at baseline and during the postoperative period.

Fibrinogen and thrombin concentrations are critical for fibrin glue adherence in rat high-risk colon anastomoses

OBJECTIVE

Fibrin glues have not been consistently successful in preventing the dehiscence of high-risk colonic anastomoses. Fibrinogen and thrombin concentrations in glues determine their ability to function as sealants, healers, and/or adhesives. The objective of the current study was to compare the effects of different concentrations of fibrinogen and thrombin on bursting pressure, leaks, dehiscence, and morphology of high-risk ischemic colonic anastomoses using fibrin glue in rats.

METHODS

Colonic anastomoses in adult female Sprague-Dawley rats (weight, 250-350 g) treated with fibrin glue containing different concentrations of fibrinogen and thrombin were evaluated at post-operative day 5. The interventions were low-risk (normal) or high-risk (ischemic) end-to-end colonic anastomoses using polypropylene sutures and topical application of fibrinogen at high (120 mg/mL) or low (40 mg/mL) concentrations and thrombin at high (1000 IU/mL) or low (500 IU/mL) concentrations.

RESULTS

Ischemia alone, anastomosis alone, or both together reduced the bursting pressure. Glues containing a low fibrinogen concentration improved this parameter in all cases. High thrombin in combination with low fibrinogen also improved adherence exclusively in low-risk anastomoses. No differences were detected with respect to macroscopic parameters, histopathology, or hydroxyproline content at 5 days post-anastomosis.

CONCLUSIONS

Fibrin glue with a low fibrinogen content normalizes the bursting pressure of high-risk ischemic left-colon anastomoses in rats at day 5 after surgery.

Prevention of leakage by sealing colon anastomosis: experimental study in a mouse model

BACKGROUND

In colorectal surgery, anastomotic leakage (AL) is the most significant complication. Sealants applied around the colon anastomosis may help prevent AL by giving the anastomosis time to heal by mechanically supporting the anastomosis and preventing bacteria leaking into the peritoneal cavity. The aim of this study is to compare commercially available sealants on their efficacy of preventing leakage in a validated mouse model for AL.

METHODS

Six sealants (Evicel, Omnex, VascuSeal, PleuraSeal, BioGlue, and Colle Chirurgicale Cardial) were applied around an anastomosis constructed with five interrupted sutures in mice, and compared with a control group without sealant. Outcome measures were AL, anastomotic bursting pressure, and death.

RESULTS

In the control group there was a 40% death rate with a 50% rate of AL. None of the sealants were able to diminish the rate of AL. Furthermore, use of the majority of sealants resulted in failure to thrive, increased rates of ileus, and higher mortality rates.

CONCLUSIONS

If sealing of a colorectal anastomosis could achieve a reduction of incidence of clinical AL, this would be a promising tool for prevention of leakage in colorectal surgery. In this study, we found no evidence that sealants reduce leakage rates in a mouse model for AL. However, the negative results of this study make us emphasize the need of systemic research, investigating histologic tissue reaction of the bowel to different sealants, the capacity of sealants to form a watertight barrier, their time of degradation, and finally their results in large animal models for AL.

Cystoscopic injection of N-butyl-2-cyanoacrylate followed by fibrin glue for the treatment of persistent or massive vesicourethral anastomotic urine leak after radical prostatectomy

OBJECTIVES

Vesicourethral anastomotic urine leak is a common postoperative complication of radical prostatectomy. Herein we describe a novel method for the treatment of this complication.

METHODS

Intervention for a prolonged or massive anastomotic urine leak was required in 10 out of 1828 patients (0.5%) submitted to radical prostatectomy between 2007 and 2011. N-butyl-2-cyanoacrylate (Histoacryl) followed by fibrin glue (Greenplast) were injected under local anesthesia into vesicourethral anastomotic gaps under fluoroscopic guidance using a 20-Fr rigid cystoscope. Cystograms were taken in all patients to confirm complete urine leak resolution before the removal of the urethral catheter.

RESULTS

Cystoscopic injection of Histoacryl followed by fibrin glue was technically successful and well tolerated in all patients. The mean time from radical prostatectomy to glue injection was 16.0 days (range 12-27 days). Urethral catheterization was required for an average of 7.7 days after cystoscopic injection of fibrin glue (range 3-13 days). These measures ultimately enabled complete resolution of the urine leak in all cases. At a mean follow up of 23.3 months, all 10 patients were fully continent. The mean time to recovery of urinary continence was 20.4 weeks (range 3.9-60.0 weeks).

CONCLUSIONS

Cystoscopic injection of N-butyl-2-cyanoacrylate followed by fibrin glue into the anastomotic gap is both a feasible and effective solution in patients with a persistent or massive vesicourethral anastomotic urine leak after radical prostatectomy.

The effect of fibrin glue on the intensity of colonic anastomosis in the presence and absence of peritonitis: an experimental randomized controlled trial on rats

Aim. Anastomotic leakage after colon anastomosis is the most frequent and most feared complication with its highest mortality rate. In this study, we aimed to expose the impact of performing fibrin glue on sutured colocolic anastomosis, in the presence of experimental peritonitis, on anastomosis safety. Method. In this experimental study, the rats were divided into two groups as control group (Groups 1 and 3) and experimental group (Groups 2 and 4). They were also divided as clean abdomen (Groups 1 and 2) and infected abdomen (3 and 4) groups. Full-thickness incisions were made on the proximal colon of both groups of rats. The control group's anastomoses were conducted only with sutures, whereas in experimental group, fibrin glue was applied over the sutures. The samples were taken on the 10th day. Results. Highest values for average levels of hydroxyproline in the tissues and anastomotic bursting pressures were detected when fibrin glue was applied on sutured anastomosis in clean abdomen. In the histopathological staging performed in line with Ehrlich-Hunt model, lowest values were detected during the presence of peritonitis. Conclusion. As a result, it has been established that the use of fibrin glue over sutured colocolic anastomosis, both in clean abdomen and in the presence of peritonitis, had increased anastomosis safety.

Tissue adhesives in gastrointestinal anastomosis: a systematic review

BACKGROUND

Anastomotic leakage in gastrointestinal (GI) surgery remains a major problem. Although numerous studies have been undertaken on the role of tissue adhesives as GI anastomotic sealants, no clear overview has been presented. This systematic review aims to provide a clear overview of recent experimental and clinical research on the sealing of different levels of GI anastomosis with tissue adhesives.

METHODS

We searched MEDLINE and Embase databases for clinical and experimental articles published after 2000. We included articles only if these addressed a tissue adhesive applied around a GI anastomosis to prevent anastomotic leakage or decrease leakage-related complications. We categorized results according to level of anastomosis, category of tissue adhesive, and level of evidence.

RESULTS

We included 48 studies: three on esophageal anastomosis, 13 on gastric anastomosis, four on pancreatic anastomosis, eight on small intestinal anastomosis, and 20 on colorectal anastomosis; 15 of the studies were on humans.

CONCLUSIONS

Research on ileal and gastric/bariatric anastomosis reveals promising results for fibrin glue sealing for specific clinical indications. Sealing of pancreatico-enteric anastomosis does not seem to be useful for high-risk patients; however, research in this field is limited. Ileal anastomotic sealing was promising in every included study, and calls for clinical evaluation. For colorectal anastomoses, sealing with fibrin glue sealing seems to have more positive results than with cyanoacrylate. Further research should concentrate on the clinical evaluation of promising experimental results as well as on new types of tissue adhesives. This research field would benefit from a systematic experimental approach with comparable methodology.

Effects of chitosan on healing and strength of colonic anastomosis in rats

PURPOSE: To investigate whether chitosan application over colonic anastomosis line, provide reinforcement, and subsequently improve anastomotic healing. METHODS: Forty eight Wistar albino female rats were used and were randomly divided into four groups, 12 rats in each: The control groups (1 and 3) received no further treatment. The experimental groups (2 and 4) received chitosan application over the colonic anastomosis. After sacrifying rats at the end of the experiment (either on day three or on day seven, depending on the group), colonic bursting pressure, a hihydroxyproline level and histopathologic characteristics of the perianastomotic tissue were examined. RESULTS: At three days, chitosan and control groups had similar values for histopathologically. On day seven, chitosan group had significantly higher mean score of collagenization (p=0.007) and a significantly higher bursting pressure (p=0.038). CONCLUSION: Our study emphasizes the positive effect of chitosan in the process of collagenation in colonic anastomosis healing.

External coating of colonic anastomoses: a systematic review

PURPOSE

Colon anastomotic leakage remains both a frequent and serious complication in gastrointestinal surgery. External coating of colonic anastomoses has been proposed as a means to lower the rate of this complication. The aim of this review was to evaluate existing studies on external coating of colonic anastomoses.

METHODS

CINAHL, EMBASE, and PubMed were searched up to September 2011 to identify studies evaluating external coating of colonic anastomoses.

RESULTS

Forty studies have evaluated 20 different coating materials, of which only fibrin sealant, omental pedicle graft, and hyaluronic acid/carboxymethylcellulose have been used in humans. Fibrin sealant has shown positive, however not significant, results. Omental pedicle graft can be used safely, yet without beneficial effects, whereas hyaluronic acid/carboxymethylcellulose should be avoided due to increased complications. The remaining coating materials have solely been evaluated in experimental animals with many contradictory and few positive results.

CONCLUSIONS

External coating of colonic anastomoses has yet failed to show convincing results. Randomized clinical trials and high-quality experimental studies are warranted to determine the role of fibrin sealant, omental pedicle graft, and other coating materials for prevention of colon anastomotic leakage.

Endoskopische Möglichkeiten der Behandlung von Nahtinsuffizienzen im Rektum

<b><i>Hintergrund: </i></b>Anastomoseninsuffizienzen stellen eine gefürchtete Komplikation der kolorektalen Chirurgie dar. Endoskopische Techniken haben sich in der Therapie der Leckagen zunehmend etabliert. In dieser Übersicht möchten wir einen Überblick der wichtigsten endoskopischen Verfahren geben. <b><i>Methode: </i></b>Systematische Recherche der vorhandenen Literatur. <b><i>Ergebnisse: </i></b>Die bedeutendsten endoskopischen Verfahren zur Behandlung der kolorektalen Anastomoseninsuffizienzen stellen die Fibrininjektion, die Vakuumschwammtherapie (Endo-Sponge), spezielle Clip-Systeme (OTSC) sowie die Stentimplantation dar. Der breiten klinischen Anwendung dieser Verfahren steht jedoch eine unzureichende Studienlage gegenüber. <b><i>Schlussfolgerung: </i></b>Die Einschätzung der Wertigkeit der einzelnen endoskopischen Verfahren untereinander und in speziellen therapeutischen Situationen hängt im Wesentlichen von der Erfahrung der Untersucher ab. Es bedarf der Durchführung randomisierter, prospektiver Studien, um diese Erfahrungen zu objektivieren.

The effect of erythropoietin on anastomotic healing of irradiated rats

AIM

The aim of the present study is to evaluate the possible protective effects of erythropoietin (EPO) on anastomotic wound healing after preoperative radiotherapy according to its pleiotropic mechanism of action.

METHODS

Thirty-two male Wistar albino rats were randomized into four groups containing eight rats each: ANAS group, standard resection plus anastomosis; RT+ANAS group, radiation plus standard resection plus anastomosis; ANAS+EPO group, standard resection plus anastomosis plus EPO; RT+ANAS+EPO, radiation plus standard resection plus anastomosis plus EPO. All animals were sacrificed by cardiac puncture, and anastomotic healing was measured by bursting pressure, hydroxyproline (OHP) levels, myeloperoxidase (MPO) activity and histopathological evaluations. Malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and matrix metalloproteinase-9 (MMP-9) were also measured in serum specimens.

RESULTS

OHP levels in the RT+ANAS + EPO group were significantly increased compared with other groups (p < .05). In contrast, MPO activity in the RT+ANAS+EPO group was significantly decreased compared with other groups (p < .05). Serum MDA levels were found to be decreased in the ANAS+EPO and RT+ANAS+EPO groups (p < .05). Group comparisons demonstrated that bursting pressure was significantly higher in EPO treated rats (p < .05). The histopathology results revealed that EPO treatment improves anastomotic wound healing though decreased necrosis and inflammatory cell infiltration and increased fibroblast activity.

CONCLUSION

The findings of the present study indicate that EPO contributes to wound healing and the strength of colon anastomosis following radiation due to its antioxidant and anti-inflammatory effects, but further studies are needed to explore the significance of these effects.

Fibrin glue with gentamicin as an alternative to conventional surgery in experimental treatment of duodenal fistula in rats

Duodenal fistula is a significant ongoing surgical problem. Minimal invasive treatment might be an alternative to conventional open surgery. This study aimed to investigate whether addition of gentamicin to fibrin adhesive can augment current surgical methods. Having established a fistula, the defect was closed using the following: simple suturing, suturing covered with fibrin sealant only, or suturing with fibrin sealant mixed with gentamicin. Bursting pressure and macroscopic and microscopic examination were evaluated on the second and sixth day after surgery. The study demonstrated there was no significant difference in overall outcome between the 3 groups. However, on macroscopic examination, the mixture of antibiotic and fibrin adhesive decreased formation of adhesions and abscesses. Microscopically, there was decreased inflammation, improved granulation, and earlier onset of fibrin filament deposition, possibly leading to enhanced wound healing. The addition of gentamicin to fibrin sealant can be a useful adjunct to standard surgical closure in duodenal fistula management.

Topical gentamicin does not provide any additional anastomotic strength when combined with fibrin glue

BACKGROUND

We evaluated the effect of a combination of fibrin sealant and topical gentamicin on a colonic anastomosis in a rat model.

METHODS

Partial anastomosis in the transverse colon was performed in 70 male Sprague-Dawley rats aged 6 to 10 weeks using 5 interrupted sutures. The rats were divided into 4 groups (control, gentamicin, fibrin glue, and combination). On postoperative days 3 and 5, the rats in each group were killed, anastomotic bursting pressures scores and bowel loop adhesions were determined, and histologic examination was performed.

RESULTS

No significant difference was noted in the bursting pressures, adhesions, inflammatory infiltrates, fibroblasts, or neoangiogenesis between the fibrin-glue only and the combination groups for both the day 3 and day 5 subgroups.

CONCLUSIONS

The combination of topical gentamicin and fibrin glue had little effect because the combination did not provide additional anastomotic strength or decrease the number of adhesions when compared with fibrin glue alone.

Protection of intestinal anastomosis with biological glues: an experimental randomized controlled trial

BACKGROUND

The aim of the study was to compare the degree of healing and air tightness of hand-sewn colonic anastomoses provided by different biological glues.

METHODS

Thirty colonic anastomoses were fashioned in ten rabbits, at 5, 10, 15 cm from the ileocecal valve, with 4/0 PDS running sutures. Each suture was randomized to treatment with fibrin sealant (Tissucol®), a synthetic glue (Coseal®), or nothing (control). After 15 days, the rabbits were killed and the anastomoses examined for their integrity and resistance to bursting. The van der Hamm scale was used to evaluate postoperative adhesions. A blind histological evaluation of the newly formed tissue was made (Ehrlich-Hunt scale).

RESULTS

Two rabbits developed an intraabdominal abscess, one in the control anastomosis group without glue. Postoperative adhesions were present in all animals. Median anastomosis bursting pressures were 0.9 atm in all three groups: Tissucol, Coseal, and control. Pressure values were 0.9, 1.0, and 0.9 atm in the three different proximodistal sites, respectively. A trend toward an increased resistance was observed in the glued anastomosis, although this was not significant. Lymphocyte infiltration, fibroblast activity, blood vessel density, and collagen deposition were lower in controls. Anastomoses treated with Tissucol had the highest lymphocyte infiltration level. The Coseal group developed the highest rates of fibroblast activity, collagen deposition, and blood vessel neogenesis.

CONCLUSION

The use of biological glues did not result in a statistically significantly increased bursting resistance. Histological evaluation demonstrated more intense tissue neoformation in the glue groups, particularly in the Coseal group. The role of biological glues in decreasing the leakage rate of intestinal anastomoses is uncertain, and larger trials using different protective agents are warranted.

Collagen fleeces do not improve colonic anastomotic strength but increase bowel obstructions in an experimental rat model

PURPOSE

To investigate whether a collagen fleece kept in place by fibrin glue might seal off a colorectal anastomosis, provide reinforcement, and subsequently improve anastomotic healing.

METHODS

Wistar rats underwent a 1-cm left-sided colonic resection followed by a 4-suture end-to-end anastomosis. They were then randomly assigned to one of three treatment groups: no additional intervention (control, n = 20), the anastomosis covered with fibrin glue (fibrin glue, n = 20), the anastomosis covered with a collagen fleece, kept in place with fibrin glue (collagen fleece, n = 21). At either 3 or 7 days follow-up, anastomotic bursting pressure was measured and tissue was obtained for histology and collagen content assessment after which animals were sacrificed.

RESULTS

Three rats in the control (15%), three in the fibrin glue (15%), and one in the collagen group (4.8%) died due to anastomotic complications (P = 0.497). Anastomotic bursting pressures were not significantly different between groups at 3 and 7 days follow-up (P = 0.659 and P = 0.427, respectively). However, bowel obstructions occurred significantly more often in the collagen group compared to the control group (14/21 vs. 3/20, P = 0.003). Collagen contents were not different between groups, but histology showed a more severe inflammation in the collagen group compared to the other groups at both 3 and 7 days follow-up.

CONCLUSIONS

A collagen fleece kept in place by fibrin glue does not improve healing of colonic anastomoses in rats. Moreover, this technique induces significantly more bowel obstructions in rats, warranting further study before being translated to a clinical setting.

The effect of sealing with a fixed combination of collagen matrix-bound coagulation factors on the healing of colonic anastomoses in experimental high-risk mice models

PURPOSE

Experimental and clinical studies on the sealing of colorectal anastomoses in order to reduce the rate of leakage have previously been performed with divergent results. However, comparatively few studies have been performed on anastomotic healing using a fibrin glue-coated patch. The aim of this experimental basic scientific study in mice was to investigate the effect of fibrin glue-coated collagen patches on the healing process of colonic anastomoses in situations of adverse healing process (technical deficiency and peritonitis).

METHODS

Colonic anastomoses were carried out in 206 mice and randomized into six groups (I: complete anastomoses, II: sealed complete anastomoses, III: incomplete anastomoses, IV: sealed incomplete anastomoses, V: complete anastomoses in the presence of bacterial peritonitis, VI: sealed complete anastomoses in the presence of bacterial peritonitis). Tissues from the anastomoses were removed and used for functional, histochemical, molecular, and biochemical investigations.

RESULTS

The evaluation of postoperative course data revealed the beneficial effect of additional sealing with a fixed combination of collagen matrix-bound coagulation factors I and IIa (Tachosil(®), Nycomed Austria, Linz) in high-risk experimental anastomotic healing. Sealing incomplete anastomoses resulted in significantly lower lethality and leakage rates, as well as significantly higher bursting pressure values and histopathologic scores. Collagen 1 and 3 expressions and hydroxyproline concentrations are greatly increased with additional sealing in all high-risk anastomoses.

CONCLUSIONS

In our current model, we demonstrate that additionally sealing high-risk experimental colonic anastomoses provides a positive effect on the healing process. The effect on the molecular level in particular seems to be essential and requires further experimental studies to evaluate the mechanism.

Butyrate enemas improve intestinal anastomotic strength in a rat model

INTRODUCTION

Anastomotic leakage is a common clinical complication with incidences up to 10% to 17% in colorectal surgery, leading to high morbidity and mortality. Butyrate is the product of colonic fermentation of indigestible carbohydrates and is considered beneficial to gastrointestinal healing. The aim of this study was to investigate the effect of intraluminal supplementation of butyrate on colonic anastomotic strength in a rat model.

METHODS

Wistar rats were randomly assigned to one of 3 groups (18 animals each). All rats underwent a 1-cm left colonic resection and end-to-end anastomosis with 4 interrupted sutures. Group I underwent no other treatment and served as the control, group II received daily 5 mL of 60 mM sodium butyrate enemas postoperatively, and group III received placebo enemas. On the third or seventh postoperative day, rats (n = 9 per time point) were anesthetized and anastomotic bursting strength was assessed.

RESULTS

As a consequence of anastomotic leakage, 3 rats (16.6%) in group I, 1 rat (5.6%) in group II, and 2 rats (11.2%) in group III died. Mean anastomotic bursting pressures at day 3 were not significantly different between groups (53, 64, and 68 mm Hg for group I, II, and III, respectively, P = .777). At day 7, bursting pressures were 118, 225, and 129 mm Hg for groups I, II, and III, respectively (P = .0006). Group II showed an increased mature-to-immature collagen ratio (P = .035).

CONCLUSION

Postoperative intestinal butyrate supplementation enhances anastomotic bursting strength in a left-sided partial colonic resection rat model, which can be explained by increased collagen synthesis and maturation.

The integrity of colonic anastomoses following the intraperitoneal administration of oxaliplatin

INTRODUCTION

The purpose of this experimental study was to determine the effect of oxaliplatin on the integrity of colonic anastomoses which were under oxaliplatin administration.

MATERIALS AND METHODS

Thirty rats were randomized to two groups. After resection of a 1-cm segment of the transverse colon, an end-to-end sutured anastomosis was performed. Rats of the control group were injected with 3 ml of 0.9% sodium chloride solution and in the oxaliplatin group with 2.4 mg/kg of oxaliplatin intraperitoneally immediately after surgery and for seven postoperative days. All rats were sacrificed on the tenth postoperative day, and the anastomoses were examined macroscopically and graded histologically. Rats were measured for anastomotic bursting pressures and tissue hydroxyproline levels.

RESULTS

The body weight changes were significantly greater in the oxaliplatin group (p = 0.005). Anastomotic dehiscence occurred only in the oxaliplatin group. The adhesion formation was significantly increased in the group of oxaliplatin compared to the control group (p = 0.001). The colonic bursting pressure was significantly lower in the oxaliplatin group compared to the control group (p < 0.001). The mean inflammatory cell infiltration was significantly lower in the oxaliplatin group (1.00 vs. 2.33, p < 0.001). The mean neoagiogenesis was significantly lower in the oxaliplatin group (0.80 vs. 2.20, p < 0.001). The mean collagen deposition was significantly lower in the oxaliplatin group and the mean fibroblast activity was significantly lower in the oxaliplatin group (1.27 vs. 2.53, p < 0.001). Hydroxyproline concentration was significantly lower in the oxaliplatin group (p < 0.001).

CONCLUSION

Intra- and postoperative intraperitoneal administration of oxaliplatin definitely impairs healing of colonic anastomoses in rats.

Covering the colon anastomoses with amniotic membrane prevents the negative effects of early intraperitoneal 5-FU administration on anastomotic healing

PURPOSE

This study investigated whether covering the colonic anastomoses with amniotic membrane (AM) protects the anastomotic healing from the adverse effects of immediate 5-fluorouracil (5-FU) administration.

METHODS

One hundred twenty wistar albino rats were randomized to one of four groups (I-IV, 30 rats in each) and underwent a standardized left colon resection and anastomoses. The anastomoses of the rats in groups II (AM) and IV (5-FU + AM) were covered with AM. Saline solution (2 ml/day; groups I (control) and II) or 5-FU (20 mg/kg/day; groups III (5-FU) and IV) was administered to the rats intraperitoneally once daily from the day of operation until sacrificed. Half of each group was sacrificed on the postoperative day 4 (IA, IIA, IIIA, and IVA) and other half on the postoperative day 8 (IB, IIB, IIIB, and IVB), and their anastomoses were evaluated when sacrificed.

RESULTS

The dehiscence rate of anastomotic dehiscence and adhesion formation were significantly higher in groups IIIA and IIIB compared with groups IVA and IVB, respectively. Bursting pressure was significantly higher in the 5-FU + AM groups than in the 5-FU groups. The inflammatory cell infiltration was significantly lower in groups IIIA and IVA compared with group IA, in groups IIIB and IVB compared with group IB, and in group IVA compared with group IIIA. Neoangiogenesis, fibroblast activity, collagen deposition, and hydroxyproline levels were significantly higher in the 5FU + AM groups compared with control and 5-FU groups. Malondialdehyde levels were significantly higher in the 5-FU groups than in the 5-FU + AM groups.

CONCLUSION

Covering colon anastomoses with AM protects them, preventing leakage and reversing the negative effects of 5-FU administration.

Effect of the combination of fibrin glue and growth hormone on intestinal anastomoses in a pig model of traumatic shock associated with peritonitis

BACKGROUND

Intra-abdominal sepsis and hemorrhagic shock have been found to impair the healing of intestinal anastomoses. The present study examined whether fibrin glue (FG) and recombinant human growth hormone (GH) can improve intestinal primary anastomotic healing in a pig model of traumatic shock associated with peritonitis. Further, the study was designed to investigate the probable mechanism of these agents.

METHODS

Female anesthetized pigs were divided into five groups. Group sham (n = 7), pigs without traumatic shock had small bowel resection anastomoses; group control (n = 14), pigs had bowel resection anastomoses 24 h after abdominal gunshot plus exsanguination/resuscitation; group FG (n = 14); group GH (n = 14); group FG/GH (n = 14), pigs received FG, recombinant GH, or both, respectively. Recombinant GH was given daily for 7 days. Blood samples were collected daily for measurement of interleukin-6 (IL-6) and tumor necrosis factor (TNF)-alpha levels. Investigations also included adhesion formation, anastomotic bursting pressure, tensile strength, hydroxyproline (HP) content, myeloperoxidase (MPO), tumor necrosis factor (NF)-kappaB activity, and histology analysis 10 days later. A second experiment (n = 20 subjects assigned to each of the five groups) was designed to study survival during the first 20 postoperative days.

RESULTS

Traumatic shock associated with peritonitis led to significant decreases in intestinal anastomotic bursting pressures, tensile strengths, and tissue hydroxyproline content, along with severe adhesion formation, increases in MPO activity and NF-kappaB activity, and plasma levels of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6). Both FG and recombinant GH treatment led to early significant increases in plasma levels of TNF-alpha and IL-6. At the same time, FG alone, unlike recombinant GH alone, led to significant increases in anastomotic bursting pressures, tensile strength, and tissue HP content, along with decreases in anastomotic MPO and NF-kappaB activity and later plasma levels of TNF-a and IL-6. The FG group also developed more marked neoangiogenesis and collagen deposition on histology analysis. However, FG and recombinant GH synergistically effected improved anastomotic healing, abolishing the infaust effects promoted by recombinant GH. Adhesion formation after intestinal anastomosis could not be lowered by FG alone or by the combination of FG and recombinant GH. Both FG alone and FG/GH, in contrast to GH alone and control treatment, significantly prolonged the survival time of experimental animals.

CONCLUSIONS

We found that FG, but not recombinant GH, could lower the risk of anastomotic leakage, improve intestinal anastomotic healing, and prolong survival in a pig model of traumatic shock associated with peritonitis. Both FG and recombinant GH synergistically effected improved intestinal anastomotic healing. It was suggested that GH could be used locally to promote intestinal anastomotic healing in intra-abdominal peritonitis.

Granulation tissue formation at the bronchial stump is reduced after stapler closure in comparison to suture closure in dogs

The aim of this study was to compare the morphology of the bronchial stump after lobectomy between mechanical stapler closure and manual suture closure. The effect of fibrin glue application on each method of closure was also observed. Right upper lobectomy was performed in beagles (n=31) using staplers (ST group) or sutures (SU group). In a separate experiment, fibrin glue was sprayed onto the stump after each respective method of closure. After one week, the stump region was examined macroscopically, and also by histology. chi(2)-Test and Mann-Whitney test were used for comparative analysis. The incidence of adhesion formation between the surrounding tissues was significantly reduced in the ST group in comparison to the SU group (22 vs. 80%, P=0.04). The thickness of granulation tissue over the stump was significantly reduced in the ST group in comparison to the SU group (0.8+/-0.2 vs. 2.5+/-0.3 mm, P<0.0001). Vessel density in the granulation tissue was also significantly reduced in the ST group in comparison to the SU group (6+/-2 vs. 16+/-2, P=0.003). Fibrin glue application after stapler closure significantly increased the incidence of adhesion formation, granulation tissue thickness, and vessel density in the granulation tissue over the stump.

Effects of amniotic membrane on the healing of normal and high-risk colonic anastomoses in rats

BACKGROUND

This study was aimed at examining whether or not the addition of amniotic membrane to a sutured colonic anastomosis improves its healing.

MATERIAL AND METHODS

Ninety female Sprague Dawley rats were used in the study. Ten served as controls for bursting pressure measurement, while the other 80 animals were divided into four groups: Anastomosis group (NA), high-risk anastomosis group (HRA), anastomosis plus amniotic membrane group (NA-AM), and high-risk anastomosis plus amniotic membrane group (HRA-AM). The last two groups had amniotic membrane covering their anastomoses. Anastomotic evaluation was carried out on the third (NA3, HRA3, NA-AM3, and HRA-AM3, respectively) and seventh (NA7, HRA7, NA-AM7, and HRA-AM7, respectively) postoperative days. The main outcome measures were gross anastomotic healing, adhesion formation, mechanical strength, hydroxyproine content, and parameters of histopathological healing.

RESULTS

Anastomotic dehiscence rate was 66.7%, 40%, 20%, and 10% in group HRA7, HRA3, NA7, and NA3, respectively. However, there was no significant difference between groups regarding the dehiscence rate. The adhesion scores were significantly higher in groups NA3 and HRA3 compared with groups NA-AM3 and HRA-AM3, respectively (p < 0.05, p < 0.001). Bursting pressure was significantly higher in groups with amniotic membrane compared without amniotic membrane (p < 0.05, for all comparison). Inflammatory cell infiltration was significantly lower in groups with amniotic membrane compared with groups without amniotic membrane (p < 0.05, for all both comparisons). Neoangiogenesis was significantly higher in the NA-AM3 and HRA-AM3 groups compared with the NA3 (p < 0.01) and HRA3 (p < 0.05) groups, respectively. Fibroblast activity was significantly higher in groups NA-AM3 and NA-AM7 compared with groups NA3 (p < 0.05) and NA7 (p < 0.05), respectively. Collagen deposition and hydroxyproline concentrations were significantly higher in groups with amniotic membrane compared with groups without amniotic membrane (p < 0.05, for all both comparisons).

CONCLUSION

The covering of both normal and high-risk colonic anastomoses with amniotic membrane provides a beneficial effect over conventional suturing of healing.

Anastomotic leakage after laparoscopic resection of rectal cancer: the impact of fibrin glue

BACKGROUND

The aim of this study was to evaluate whether the use of fibrin glue as a sealant over an anastomosis is a risk factor for anastomotic leakage after laparoscopic rectal cancer surgery.

METHODS

Prospective data were collected from 223 patients with rectal cancer who underwent laparoscopic resection without defunctioning stoma.

RESULTS

A total of 104 patients underwent laparoscopic rectal resection, followed by the application of fibrin glue over the stapled anastomosis, while 119 underwent surgery alone. No difference in clinically significant leakage was observed between the fibrin and the nonfibrin groups (5.8% vs 10.9%, P = .169). In multivariate analysis, extraperitoneal tumor location and operation duration >220 minutes were independently associated with anastomotic leakage.

CONCLUSIONS

Significant predictors of anastomotic leakage include extraperitoneal tumor location and operation length >220 minutes. Fibrin glue application over the stapled anastomosis was not found to be significantly associated with anastomotic leakage.

Healing of colonic anastomoses after immediate postoperative intraperitoneal administration of oxaliplatin

AIM

The aim of this experimental study was to investigate the effect of intraperitoneal administration of oxaliplatin on the healing of colonic anastomoses when injected immediately after colon resection.

MATERIALS AND METHODS

Thirty male Wistar rats were used. During the operation, the rats were randomized to two groups of 15 rats each. Immediately after colonic anastomoses were performed, the rats were injected intraperitoneally with either 3 ml of 0.9% NaCl solution or oxaliplatin (2.4 mg/kg body weight) depending on their group. All rats were killed on the eighth postoperative day. The anastomoses were examined macroscopically. The anastomotic bursting pressures were recorded, the anastomoses graded histologically, and the hydroxyproline tissue contents determined.

RESULTS

Anastomotic leakage was noted in four rats (26.7%) of the oxaliplatin group, whereas no anastomotic dehiscence was detected among rats of the control group (p = 0.016). The adhesion formation at the anastomotic sites and the inflammatory cell infiltration were significantly higher in the oxaliplatin group than in the control group (p = 0.001). The bursting pressures (p = 0.001), the hydroxyproline tissue content (p = 0.001), the neoangiogenesis (p = 0.033), the fibroblast activity (p = 0.001), and the collagen deposition (p = 0.001) were significantly lower in the oxaliplatin group in comparison to the control group.

CONCLUSION

The immediate postoperative intraperitoneal administration of oxaliplatin seems to impair healing of colonic anastomoses in rats.

Anastomose colônica com adesivo de fibrina em ratos diabéticos

OBJETIVO: Estudar aspectos da cicatrização na anastomose colônica com adesivo de fibrina em ratos normais e diabéticos. MÉTODO: Foram utilizados 160 ratos Wistar (Rattus novergicus albinus), machos, com peso variando de 250 a 300g, sendo que oitenta destes animais eram não diabéticos e os outros oitenta animais apresentavam diabetes mellitus induzido pela aloxana, Os animais foram submetidos a procedimento operatório padronizado que consistiu em colectomia parcial esquerda e anastomose primária por sutura manual ou com adesivo de fibrina. Foram reavaliados no quarto ou sétimo dia de pós-operatório quando se observou a presença de coleção líquida ou purulenta na tela subcutânea; integridade da sutura; presença de aderências; presença de deiscência; resistência da anastomose (pressão máxima de insuflação) em mmHg, e a concentração tecidual de hidroxiprolina. RESULTADOS: Em relação à presença de deiscência de anastomose e mortalidade ocorreram piores resultados nos animais diabéticos no quarto e sétimo dias de observação em comparação ao controle. Nos grupos e subgrupos estudados os resultados com o uso do adesivo de fibrina não foram melhores que os da sutura manual. Em relação à concentração tecidual de hidroxiprolina não houve diferença significativa entre os grupos. CONCLUSÃO: O diabetes mellitus induzido pela aloxana impede a reparação normal da anastomose colônica em ratos e o uso adesivo de fibrina na anastomose colônica em ratos normais e diabéticos não trouxe benefícios na evolução pós-operatória.

Sealing of gastrointestinal anastomoses with a fibrin glue-coated collagen patch: a safety study

Sealing of anastomoses has previously been tested with several methods, including sealing with liquid fibrin glue. Sealing with a collagen patch coated with fibrin glue components has never been systematically examined. The aim of the present study was to determine the safety of sealing gastrointestinal anastomoses with a collagen patch coated with fibrin glue. The study is a prospective, experimental animal study comparing sealed and unsealed gastrointestinal anastomoses. Laparotomy was performed in 11 pigs under general anesthesia. In each pig two anastomoses were performed on the small intestine. One of the anastomoses was sealed with a collagen patch coated with fibrin glue components (TachoSil). The other anastomosis contained no sealing. The pigs were observed for 1 to 6 weeks. The observation period was followed by in vivo examination under general anesthesia and included observation for anastomotic leakage, signs of present or former peritonitis, abscess, adhesions to the anastomoses, and signs of intestinal obstruction. In addition, the anastomotic diameter was measured with barium and radiography. Finally, bursting pressure was measured in each segment. After the pigs were sacrificed, the bowel segments were microscopically examined. There were no differences between the sealed and the unsealed anastomoses with respect to abdominal pathology, in vivo bursting pressure, or degree of stenosis. The collagen fleeces were in situ in all anastomoses. Microscopically, we found no difference in healing or signs of infection.

The impact of different closure materials on pharyngeal wound healing: an experimental animal study

The formation of pharyngo-cutaneous fistula (PCF) is controversial and various predisposing factors have been proposed. This study aimed to compare different suture materials in the closure of pharyngeal wounds in experimental animals. Fifty-two Sprague-Dawley rats were divided into three groups. Artificial pharyngotomy was performed and was then repaired with Vicryl, polypropylene, and Vicryl plus fibrin glue, respectively. Outcome measurements included gross wound inspection and histological examination. There was a significant difference in the rates of PCF formation between group I and group II (Fisher's exact test, p = 0.046). In addition, minimal inflammatory response was found in the polypropylene group when compared to the other groups. The fibrin glue-treated group had the highest fibroblast activity and collagen deposition. Polypropylene produced minimal tissue reaction, which facilitated the healing process. Therefore, proper selection of suture material can probably reduce the rate of PCF but should not be substituted for proper aseptic and meticulous surgical techniques.

Hyperthermic intraperitoneal chemoperfusion (HIPEC) decrease wound strength of colonic anastomosis in a rat model

BACKGROUND AND AIMS

There is controversy about the effect of the influence of hyperthermia and chemotherapeutic agents on the healing of intestinal anastomosis. The effects of hyperthermic intraperitoneal chemoperfusion (HIPEC) of wound healing after colonic anastomosis were investigated in a rat model.

MATERIALS AND METHODS

Thirty-six Wag/Rija rats were randomized into three groups of 12 animals each: group I: control (only colonic anastomosis was performed) (n = 12); group II: HIPEC (mitomycin C in a concentration of 20 mg/m(2) (n = 12) colonic anastomosis was performed before HIPEC; group III: HIPEC (mitomycin C in a concentration of 20 mg/m(2) (n = 12) colonic anastomosis was performed after HIPEC. Bursting pressure and bursting sites were recorded 4 and 10 days after intervention. Collagen deposits, inflammation and foreign body reactions were evaluated.

RESULTS

Lower bursting pressure and lost of collagen were found in both HIPEC groups and compared with the control group. There was almost no difference between both HIPEC groups. They were noted overwhelmingly at the anastomosis in the HIPEC group. The degree of collagen accumulation was well-correlated with bursting pressure.

CONCLUSION

These results have shown that hyperthermic intraperitoneal chemoperfusion (HIPEC) impairs wound healing in colonic anastomosis in rats.

Effect of IGF-I on healing of colonic anastomoses in rats under 5-FU treatment

BACKGROUND

The aim of this experimental study was to investigate whether insulin-like growth factor I (IGF-I) can protect the colonic healing from the adverse effects of intraperitoneal administration of 5-fluorouracil (5-FU).

MATERIALS AND METHODS

Eighty male Wistar rats were randomized into four groups of 20 rats each. Immediately after anastomoses were performed, rats in the control group were injected with 1 mL/100 gr of intraperitoneal saline solution, which was repeated daily until killed. Rats in the 5-FU and IGF-I +5-FU groups received 5-FU in a dose of 20 mg/kg body weight intraperitoneally, from the day of operation until killed. Rats in the IGF-I and IGF-I +5-FU groups received IGF-I in a dose of 2 mg/kg body weight intraperitoneally, immediately after the colonic anastomosis was performed and on 2nd, 4th, and 6th postoperative day. Rats were sacrificed on the 7th postoperative day.

RESULTS

The dehiscence rate in the 5-FU group was 30% and it was significantly higher compared with the control and the IGF-I group (P = 0.020 for both comparisons). However, in the IGF-I +5-FU group, the dehiscence rate decreased to 10%. The administration of IGF-I resulted in a significant rise of bursting pressure in the IGF-I +5-FU group compared with the 5-FU group (P < 0.001). There was no statistical difference in bursting pressure between the IGF-I +5-FU and control groups (P = 1.000). The hydroxyproline levels were higher in the IGF-I and the IGF-I +5-FU groups as a result of the stimulating act of IGF-I.

CONCLUSION

IGF-I, when given intraperitoneally, seems to mediate some of the adverse effects of 5-FU on the colonic healing in rats.

Effect of iloprost on impaired anastomotic healing caused by 5-fluorouracil plus leucovorin

PURPOSE

This experimental study was designed to investigate whether iloprost can reverse impaired colonic healing caused by immediate postoperative intraperitoneal administration of 5-fluorouracil plus leucovorin.

METHODS

Eighty Wistar rats were randomized into four groups. After resection of a 1-cm segment of transverse colon, an end-to-end sutured anastomosis was generated. Rats received saline solution (Group 1), 5-fluorouracil plus leucovorin (Group 2), iloprost (Group 3), and 5-fluorouracil plus leucovorin plus iloprost (Group 4) intraperitoneally from the day of operation and once daily until killing. Each group was further randomized into two subgroups. Subjects were killed on the fifth (Subgroup a) and eighth (Subgroup b) postoperative days. After killing, anastomoses were examined macroscopically and graded histologically. Rats were measured for anastomotic bursting pressures and tissue hydroxyproline levels.

RESULTS

The leakage rate of the anastomoses was significantly higher in the 5-fluorouracil plus leucovorin group compared with the other groups (P = 0.049). Bursting pressure was significantly lower in 2a subgroup (5-fluorouracil plus leucovorin, postoperative Day 5) than in 4a (5-fluorouracil plus leucovorin plus iloprost, postoperative Day 5; P < 0.001). Adhesion formation was significantly higher in all b subgroups compared with the Control b subgroup. Neoangiogenesis was significantly higher in iloprost and iloprost plus 5-fluorouracil plus leucovorin subgroups compared with the 5-fluorouracil plus leucovorin subgroups. Hydroxyproline levels, collagen deposition, fibroblasts, and white cell count were significantly higher in the iloprost plus 5-fluorouracil plus leucovorin b subgroup (postoperative Day 8) compared with the 5-fluorouracil plus leucovorin b subgroup (postoperative Day 8).

CONCLUSIONS

The immediate postoperative, intraperitoneal administration of iloprost counteracts and reverses the negative effects of 5-fluorouracil plus leucovorin chemotherapy and protects colonic healing in rats.

Influência da cola Bioglue® na deiscência de anastomose colônica: estudo experimental

A grande parte da morbimortalidade associada com a cirurgia colorretal, é associada com a deiscência anastomótica. Trabalhos experimentais sobre a utilidade de adesivos tissulares nas anastomoses colônicas são controversos, assim como estudos clínicos prospectivos randomizados são ausentes. O adesivo cirúrgico BioGlue®, formado por dois componentes - albumina sérica bovina purificada e glutaraldeído, forma uma ligação co-valente entre esses dois componentes e as proteínas teciduais no local de aplicação. O objetivo do estudo é avaliar a eficácia da BioGlue® na prevenção da deiscência anastomótica colônica em ratos. Foram utilizados 30 ratos machos da raça Wistar albino. A anastomose colocolônica foi confeccionada com sutura em pontos separados com polipropileno 5-0 (grupo 1) e aplicação da cola BioGlue® envolvendo a anastomose (grupo 2). Avaliaram-se a formação e extensão das aderências, a pressão de ruptura nas anastomoses e as alterações histológicas. Apenas um animal do grupo 1 (7%) faleceu, sendo constatada na necropsia, obstrução intestinal com grande distensão de alças. A mortalidade no grupo 2, por outro lado, foi de 10 animais (67%), sendo observado: distensão de alças intestinais, vazamento anastomótico e, em algumas situações, franca peritonite fecal por deiscência quase que total da anastomose. O presente trabalho nos permitiu concluir que, o uso da Bioglue® nas anastomoses colônicas realizadas em ratos, promoveu um aumento na morbimortalidade que foi estatisticamente significante comparado à sutura convencional.

Effect of the Combination of Fibrin Glue and Growth Hormone on Incomplete Intestinal Anastomoses in a Rat Model of Intra-Abdominal Sepsis

BACKGROUND

The presence of established intra-abdominal sepsis has been considered a contraindication to primary anastomoses. Our hypothesis was that fibrin glue (FG), growth hormone (rhGH), and combination of them synergistically improve intestinal primary anastomotic healing in a rat model of intestinal fistulae with peritonitis.

MATERIALS AND METHODS

Male Wistar rats, induced intestinal fistulae with peritonitis after 24 h, were performed an enterectomy and intestinal anastomoses. Group A, rats (n = 60) had a complete anastomoses (end-to-end single layer anastomoses using 12 inverted interrupted 6-0 sutures) without peritonitis, group B, rats (n = 60) had a complete anastomoses after 24 h of peritonitis, group C rats had an incomplete anastomoses (four inverted interrupted sutures), groups D, E, F rats (n = 60) received FG, rhGH, or both of them, respectively. rhGH was given daily for 5 days. Anastomoses indicated the anastomotic bursting pressure (ABP), tensile strength, and hydroxyproline content, were determined.

RESULTS

On POD 1, ABP of group C and group D was significantly lower than that of other groups (P < 0.01); On POD 3, ABP could not be determined because of intestinal dehiscence in groups C and E, ABP was significantly higher in groups D and F than that of groups A and B (P < 0.01); the ABP increased after 5 days of operation in groups A, B, and F. At the same time, that of group D decreased (P < 0.01). On POD 5, the tensile strength was significantly higher in groups A, D, and F than that in groups C, and E. On POD 5, hydroxyproline content was higher in groups D and F compared to that in group C (P < 0.05).

CONCLUSIONS

These data suggested that FG improve intestinal primary anastomotic healing within post-operative 5 days in a rat model of intestinal fistulae with peritonitis. RhGH alone fails to improve intestinal anastomotic healing, and the combination of FG and rhGH have no synergistic effect to improves intestinal anastomotic healing.

Optical-Access Visual Obturator Trocar Entry into Desufflated Abdomen During Laparoscopy: Assessment After 96 Cases

BACKGROUND

The introduction of optical-access laparoscopic trocars was met with enthusiasm and the impression that these devices provide safer access with decreased complication rates. However, serious complications have been reported.

PATIENTS AND METHODS

We retrospectively reviewed our first 96 consecutive cases (17 radical prostatectomies, 2 sacrocolpopexies, 6 adrenalectomies, and 71 renal procedures), performed between October 2001 and April 2003, of optical-access laparoscopic trocar placement as initial entry into the desufflated abdomen. After creating a 12-mm periumbilical or lateral-rectus incision, the 12-mm Endopath Bladeless visual obturator trocar (Ethicon Endosurgery, Cincinnati, OH) was inserted into the peritoneum while carefully observing the separation of the layers of fascia, muscle, and peritoneum.

RESULTS

There were no vascular injuries. However, we observed 2 (2.1%) large-bowel injuries: a seromuscular injury and a through-and-through enterotomy of the mid-descending colon. In both cases, the visual obturator was placed lateral to the left rectus muscle, and the large colon was noted to be adherent to the anterior abdominal wall. The bowel injuries were repaired in two layers (running 3-0 Vicryl for the mucosa and 3-0 silk for the seromuscular layer). The operations were completed without open conversion and with uneventful recovery.

CONCLUSIONS

Direct placement of an optical-access visual obturator trocar into the desufflated abdomen carries the potential for significant injury. Our current practice is to place the visual trocar after Veress-needle peritoneal insufflation.