The healing of colon anastomosis covered with fibrin glue after early postoperative intraperitoneal chemotherapy

Sustained-released mixture of vascular endothelial growth factor 165 and fibrin glue strengthens healing of ileal anastomoses in a rabbit model with intraperitoneal infection

Purpose

To investigate the effects of a sustained-released mixture of vascular endothelial growth factor 165 (VEGF165) and fibrin glue (FG) local administration on postoperative rabbit ileal anastomoses.

Methods

One hundred twenty-eight male and female New Zealand white rabbits underwent intraperitoneal infection subsequent ileal anastomosis surgery were divided randomly into 4 groups, including 32 animals in each, applied with saline solution, FG, rhVEGF165 and a mixture of rhVEGF165 with FG (VEGF + FG) on the anastomoses, respectively. The incidences of anastomotic leakage were observed. Histopathological examination for inflammatory infiltration, fibroblast proliferation, and capillary vascular proliferation were performed. Then, bursting pressure and hydroxyproline concentrations were assessed in anastomoses sits on postoperative days 3, 5, 7, and 14.

Results

Rabbits in VEGF + FG group had the lowest incidence of leakage (P < 0.05). Histological evaluations revealed that granulation tissue was formed on days 5 after anastomosis; fibroblast proliferation and capillary vascular proliferation were significantly increased on days 7 and 14 in VEGF + FG group. Furthermore, there was a statistically significant difference in the mean bursting pressures between VEGF + FG group and other groups on days 7 and 14 (P < 0.05), and rabbits in VEGF + FG group exhibited a higher concentration than VEGF group (P < 0.05) and FG group (P < 0.05) on day 14.

Conclusion

Administration of VEGF165 mixed with FG to ileal anastomosis accelerates wound healing and enhances the anastomosis by increased angiogenesis.

Human Amniotic Membrane Is Not Suitable for the Grafting of Colon Lesions and Prevention of Adhesions in a Xenograft Rat Model

INTRODUCTION

New biological materials are needed for specific applications in reconstructive bowel surgery and for the prevention of adhesion formation. Amniotic membranes (AMs) are assumed to have a number of unique characteristics that enhance the ingrowth of the surrounding tissue. The aim of the present study was to provide proof of these qualities in a xenograft model.

MATERIALS AND METHODS

A multilayer human AM (HAM) was applied to repair defined colon wall defects in Sprague-Dawley rats (n = 18). The control group was repaired with a suture (n = 6). The animals were killed humanely at 7, 21, and 42 days after implantation. Adhesions and perioperative complications were examined. Histological and immunohistological analyses were performed to assess a number of parameters, including degradation of the HAM, inflammation, graft rejection, and smooth muscle ingrowth.

RESULTS

Two rats in the treated group died. No other severe complications were observed. Adhesion formation was more prominently visible in the HAM group ( P < .05). The initially increased inflammation in the HAM group reduced over time but remained significantly increased ( P < .05). The HAM degraded over time and a subtle transient glomerulitis could be observed.

CONCLUSION

HAMs were found to increase adhesion formation and were not suitable for bowel augmentation in the presented xenograft model.

The prevention of colorectal anastomotic leakage with tissue adhesives in a contaminated environment is associated with the presence of anti-inflammatory macrophages

BACKGROUND

Colorectal anastomoses created in a contaminated environment result in a high leakage rate. This study investigated whether using anastomotic sealants (TissuCol(®), Histoacryl(®) Flex, and Duraseal(®)) prevents leakage in a rat peritonitis model.

STUDY DESIGN

Sixty-seven Wistar rats were divided into control and experimental groups (TissuCol, Histoacryl, and Duraseal groups). Peritonitis was induced 1 day before surgery with the cecal ligation puncture model. On day 0, colonic anastomosis was constructed with sutures and then sealed with no adhesive (control group) or one select adhesive (experimental groups). Bursting pressure, abscess formation, and adhesion severity were evaluated on day 3 or day 14. Hematoxylin and eosin staining and immunohistochemical staining for CD4, CD8, CD206, and iNOS were performed.

RESULTS

On day 3, bursting pressures of the TissuCol group (120.1 ± 25.3 mmHg), Histoacryl group (117.3 ± 20.2 mmHg), and Duraseal group (123.6 ± 35.4 mmHg) were significantly higher than the that of the control group (24.4 ± 31.7 mmHg, p < 0.001). Abscesses around the anastomosis were found in the control group (6/7) and Duraseal group (2/9) but not in the TissuCol group or Histoacryl group. A higher number of CD206+ cells (M2 macrophages), a lower number of iNOS+ cells (M1 macrophages), a higher M2/M1 index, and a higher CD4+/CD8+ index were seen at the anastomotic site in all experimental groups compared with the control group on day 3. On day 14, abscesses were only found in the control group. Adhesion severity in the Duraseal group was significantly lower than that in the control group (p = 0.001).

CONCLUSIONS

Anastomotic sealing using TissuCol(®), Histoacryl(®) Flex, or Duraseal(®) seems to be an effective and safe option to prevent leakage in contaminated colorectal surgery. The presence of large numbers of anti-inflammatory macrophages seems to be involved in preventing the leakage.

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.

Effects of Intraperitoneal Bevacizumab Administration on Colonic Anastomosis and Early Postoperative Adhesion Formation

Aim. The purpose of this study is to investigate the effect of intraperitoneal (IP) bevacizumab on colonic anastomosis and evaluate the effects on early postoperative adhesion formation. Materials and Methods. A total of 24 mature female Sprague-Dawley rats were used for this study. Rats were randomly assigned to a control group that received saline (n = 8) or to experimental groups (n = 8 each) that received bevacizumab at a dose of 2.5 mg/kg (group 1) or 5 mg/kg (group 2). Animals were killed humanely on the seventh day after operation, and measurements of anastomotic strength and biochemical variables were performed. Results. The mean adhesion grade was 2.63 ± 0.92, and 1 ± 0.93 and 0.75 ± 0.71 for the control and test groups, respectively. Bevacizumab significantly reduced adhesion formation in both low-dose and high-dose IP applications ( P < .05). When all groups were compared, it was found that VEGF levels decreased significantly only in the tissue ( P = .001), whereas there was no significant difference in the blood and the IP fluid ( P = .73 and .08, respectively). We evaluated hydroxyproline levels, anastomosis bursting pressure, and histopathological healing scores. When each of these parameters were examined, there was statistical difference between groups ( P = .01, .004, and .01, respectively). It was found that these parameters significantly decreased depending on increasing drug dose. Conclusion. IP administration of bevacizumab effectively reduced the formation of adhesions and caused significant impairment of anastomotic wound healing when standard doses were administered (5 mg/kg), but the 2.5-mg/kg dosage did not affect the anastomotic wound healing and also effectively reduced the formation of adhesions.

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.

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.

Enhancement of colonic anastomotic strength in rats by short-chain fatty acids

BACKGROUND

The present study is aiming at elucidating the effect of intraoperative lavage with short-chain fatty acids (SCFAs) on colonic anastomosis in rats.

METHODS

Forty male Wistar rats were randomized into four groups (10 rats each). After resection of a segment of transverse colon, an end-to-end anastomosis was performed. In the 1st group, no intraoperative large bowel lavage was performed; in the 2nd, a lavage with normal saline solution; in the 3rd, the animals received a diet rich in SCFAs pre- and postoperatively, and a lavage with normal saline was performed; and in the 4th group, an intraoperative lavage with SCFAs was carried out. On the 4th postoperative day, the animals were sacrificed. Septic complications, adhesions and anastomoses were graded macroscopically and histologically, and bursting pressure of the anastomoses, CRP, IL-6 and TNF-a was measured.

RESULTS

Fewer septic complications (abscesses and minimal ruptures) and adhesions were observed in the 4th group with the intraoperative lavage with SCFAs. The bursting pressure also, in the same group, was higher (73.3 mmHg), followed by the 1st group (67.1 mmHg).

CONCLUSION

Intraoperative lavage with SCFAs increases the bursting pressure of colonic anastomoses, while lavage with saline solution decreases it, in comparison to the group without lavage.

Colorectal anastomotic leakage: a new experimental model

BACKGROUND

Anastomotic leakage is the major complication after colorectal surgery. To date, animal experiments concerning colorectal anastomosis focus on anastomotic healing instead of anastomotic leakage. This study aims to develop a new experimental model for colorectal anastomotic leakage.

METHODS

A control group, receiving an anastomosis with 12 interrupted sutures, was compared to a group receiving an anastomosis with 6 interrupted sutures. When the leakage rate was observed to be too low, the number of sutures was decreased stepwise, to 5 or less. Each group contained 9 "C57Bl6-mice". After 7 d the Anastomotic Bursting Pressure (ABP) was determined.

RESULTS

In the first experiment, one mouse (11.1%) in the case group and none in the control group developed leakage. Average ABP was 152.2 mmHg in the control group and 138,8 mmHg in the case group (P=0.111). In the second experiment, case group receiving an anastomosis with 5 sutures, 4 mice (44.4%) in the case group developed leakage. This experiment was repeated twice resulting in leakage rates of 33.3% and 44.4%. The average overall ABP in the case group was 142.7 mmHg vs. 179.9 mmHg (P=0.022) in the control group. The mice without leakage showed a stabilization of average weight loss around day 2 and 3 and a decrease afterwards. The mice with leakage showed a decrease only after day 5. The difference in wellness-scores between the groups with- and without leakage was 2 points, increasing during follow-up.

CONCLUSIONS

The model of anastomotic leakage caused by creating an anastomosis with 5 interrupted sutures is feasible. Weight loss and wellness-scores are good predictors of leakage.