The use of a novel adhesive tissue patch as an aid to anastomotic healing

Clinical results after external reinforcement of colorectal anastomosis: a systematic review

OBJECTIVE

The aim of this review is to describe and assess the existing methods to cover colorectal anastomoses with biomaterials and their clinical impact in reducing anastomotic leakage (AL).

SUMMARY BACKGROUND DATA

The most serious complication in colorectal surgery is AL. Despite improvements in its diagnosis and management, AL remains an unresolved issue. To prevent its appearance and clinical consequences, different external reinforcement techniques with synthetic or biomaterials have been described.

METHODS

A systematic review search of the available literature until June 2022 was performed, looking for all literature regarding external reinforcement of colonic or colorectal anastomoses. After the review process, a classification of materials was proposed into solid and liquid materials, and an assessment of their clinical impact was performed. The study protocol has been registered at PROSPERO and has been reported in the line with PRISMA and AMSTAR Guidelines 11,12 .

RESULTS

Ninety-seven articles that fulfilled inclusion criteria, were identified and revised. Overall, 18 of the selected articles focused on human clinical trials and 79 on animal models. Only fibrin sealants, collagen patches, and omentoplasty have shown positive results in humans.

CONCLUSIONS

Fibrin sealants, collagen patches, and omentoplasty are, so far, the most studied biomaterials. However, further studies are required to confirm these findings before definite recommendations can be made.

Surgical Sealant with Integrated Shape-Morphing Dual Modality Ultrasound and Computed Tomography Sensors for Gastric Leak Detection

Postoperative anastomotic leaks are the most feared complications after gastric surgery. For diagnostics clinicians mostly rely on clinical symptoms such as fever and tachycardia, often developing as a result of an already fully developed, i.e., symptomatic, surgical leak. A gastric fluid responsive, dual modality, electronic-free, leak sensor system integrable into surgical adhesive suture support materials is introduced. Leak sensors contain high atomic number carbonates embedded in a polyacrylamide matrix, that upon exposure to gastric fluid convert into gaseous carbon dioxide (CO2 ). CO2 bubbles remain entrapped in the hydrogel matrix, leading to a distinctly increased echogenic contrast detectable by a low-cost and portable ultrasound transducer, while the dissolution of the carbonate species and the resulting diffusion of the cation produces a markedly reduced contrast in computed tomography imaging. The sensing elements can be patterned into a variety of characteristic shapes and can be combined with nonreactive tantalum oxide reference elements, allowing the design of shape-morphing sensing elements visible to the naked eye as well as artificial intelligence-assisted automated detection. In summary, shape-morphing dual modality sensors for the early and robust detection of postoperative complications at deep tissue sites, opening new routes for postoperative patient surveillance using existing hospital infrastructure is reported.

Light-activated photosealing with human amniotic membrane strengthens bowel anastomosis in a hypotensive, trauma-relevant swine model

BACKGROUND

Gastrointestinal anastomotic leakage is a dreaded complication despite advancements in surgical technique. Photochemical tissue bonding (PTB) is a method of sealing tissue surfaces utilizing photoactive dye. We evaluated if crosslinked human amniotic membrane (xHAM) photosealed over the enteroenterostomy would augment anastomotic strength in a trauma-relevant swine hemorrhagic shock model.

METHODS

Yorkshire swine (40-45 kg, n = 14) underwent midline laparotomy and sharp transection of the small intestine 120 cm proximal to the ileocecal fold. Immediately following intestinal transection, a controlled arterial bleed was performed to reach hemorrhagic shock. Intestinal repair was performed after 60 minutes and autotransfusion of the withdrawn blood was performed for resuscitation. Animals were randomized to small intestinal anastomosis by one of the following methods (seven per group): suture repair (SR), or SR with PTB augmentation. Animals were euthanized at postoperative Day 28 and burst pressure (BP) strength testing was performed on all excised specimens.

RESULTS

Mean BP for SR, PTB, and native tissue groups were 229 ± 40, 282 ± 21, and 282 ± 47 mmHg, respectively, with the SR group statistically significantly different on analysis of variance (p = 0.02). Post-hoc Tukey all-pairs comparison demonstrated a statistically significant difference in burst pressure strength between the SR only and the PTB group (p = 0.04). All specimens in SR group ruptured at the anastomosis upon burst pressure testing, while all specimens in the PTB group ruptured at least 2.5 cm from the anastomosis.

CONCLUSION

Photosealing with xHAM significantly augments the strength of small intestinal anastomosis performed in a trauma porcine model.

DIFFERENT SURGICAL METHODS IN COLON ANASTOMOSIS: EXPERIMENTAL STUDY

Although many methods have been defined for colonic anastomosis, anastomotic leak still remains important for sepsis control and successful healing.

Use of a novel sealant film in head and neck surgery

In head and neck surgery, sealant films represent a useful adjunct to ensure a reinforcement preventing leakages, dehiscence or oozing. The aim of this pilot study is to present the potential applications of a new sealant sheet in head and neck surgery, reporting outcomes, advantages and limitations. The sample included 32 patients, that underwent oncologic or elective surgery between January 2019 and January 2021 at the Cattinara Hospital in Trieste, Italy. Data regarding the patient, the surgical procedure and the postoperative course over hospitalization in terms of surgical complications were retrospectively collected. In this study, nor complication during the regular follow-up period occurred neither difficulties emerged in TP use in any head and neck subsites. In our experience, TP represented a valid aid in suture strengthening, easy to apply and suitable also for oncologic surgery in which the closure of some surgical defects may need a greater sealing effect.

Liquid Copolymers as Biodegradable Surgical Sealant

Surgical sealants are widely used to prevent seepage of fluids and liquids, promote hemostasis, and close incisions. Despite the remarkable progress the field of biomaterials has undergone, the clinical uses of surgical sealants are limited because of their short persistence time in vivo, toxicity, and high production costs. Here, the development of two complementary neat (solvent-free) prepolymers, PEG₄ -PLGA-NHS and PEG₄ -NH₂ , that harden upon mixing to yield an elastic biodegradable sealant is presented. The mechanical and rheological properties and cross-linking rate can be controlled by varying the ratio between the two prepolymers. The tested sealants show a longer persistence time compared with fibrin glue, minimal cytotoxicity in vitro, and excellent biocompatibility in vivo. The neat, multiarmed approach demonstrated here improves the mechanical and biocompatibility properties and provides a promising tissue sealant solution for wound closure in future surgical procedures.

Comparison of the efficacy of growth factor collagen and antibiotic collagen on colon anastomosis in experimental animals with peritonitis

INTRODUCTION

In spite of advances in surgical techniques, the significance of anastomosis leak continues in colorectal surgery. There is no ideal method in spite of all studies and technical advances in this field. Our aim of this study was to use fibroblast growth factor collagen (FGF-C) and antibiotic collagen (AB-C) to increase the rate of anastomosis healing in experimental animals with peritonitis.

METHODS

This animal experimental study received ethics committee approval. The animals were divided into three groups of seven animals each; the first group was control, the second group was the fibroblast growth factor collagen group, and the third group was the antibiotic collagen group. Under anesthesia, more than 50% of the colonic lumen was opened 4-5 cm distal to the ileocecal junction to create a defect. Twenty-four hours later, primary anastomosis was performed. The second group had the anastomosis line covered with a cover containing FGF-C. The third group had the anastomosis line covered by material containing AB-C. The experiment was concluded on the postoperative 7th day, and the anastomosis burst pressure, tissue hydroxyproline level, and histopathological assessment were performed.

RESULTS

Though the burst pressure was higher in the experimental groups, it was not statistically significant. In the second and third groups, vascular proliferation and fibroblastic activity appeared to be better than in the control group. Hydroxyproline values were statistically significant in the experimental groups compared to the control group.

CONCLUSION

FGF-C and AB-C may have potential utility in anastomosis healing, especially in those susceptible to infection due to anastomosis leak.

Reinforcement of Colonic Anastomosis with Improved Ultrafine Nanofibrous Patch: Experiment on Pig

Anastomotic leakage is a dreadful complication in colorectal surgery. It has a negative impact on postoperative mortality, long term life quality and oncological results. Nanofibrous polycaprolactone materials have shown pro-healing properties in various applications before. Our team developed several versions of these for healing support of colorectal anastomoses with promising results in previous years. In this study, we developed highly porous biocompatible polycaprolactone nanofibrous patches. We constructed a defective anastomosis on the large intestine of 16 pigs, covered the anastomoses with the patch in 8 animals (Experimental group) and left the rest uncovered (Control group). After 21 days of observation we evaluated postoperative changes, signs of leakage and other complications. The samples were assessed histologically according to standardized protocols. The material was easy to work with. All animals survived with no major complication. There were no differences in intestinal wall integrity between the groups and there were no signs of anastomotic leakage in any animal. The levels of collagen were significantly higher in the Experimental group, which we consider to be an indirect sign of higher mechanical strength. The material shall be further perfected in the future and possibly combined with active molecules to specifically influence the healing process.

Experimental fortification of intestinal anastomoses with nanofibrous materials in a large animal model

Anastomotic leakage is a severe complication in gastrointestinal surgery. It is often a reason for reoperation together with intestinal passage blockage due to formation of peritoneal adhesions. Different materials as local prevention of these complications have been studied, none of which are nowadays routinely used in clinical practice. Nanofabrics created proved to promote healing with their structure similar to extracellular matrix. We decided to study their impact on anastomotic healing and formation of peritoneal adhesions. We performed an experiment on 24 piglets. We constructed 3 hand sutured end-to-end anastomoses on the small intestine of each pig. We covered the anastomoses with a sheet of polycaprolactone nanomaterial in the first experimental group, with a sheet of copolymer of polylactic acid with polycaprolactone in the second one and no fortifying material was used in the Control group. The animals were sacrificed after 3 weeks of observation. Clinical, biochemical and macroscopic signs of anastomotic leakage or intestinal obstruction were monitored, the quality of the scar tissue was assessed histologically, and a newly developed scoring system was employed to evaluate the presence of adhesions. The material is easy to manipulate with. There was no mortality or major morbidity in our groups. No statistical difference was found inbetween the groups in the matter of level of peritoneal adhesions or the quality of the anastomoses. We created a new adhesion scoring system. The material appears to be safe however needs to be studied further to prove its' positive effects.

Effects of the Folk Medicinal Plant Extract Ankaferd BloodStopper on the Healing of Colon Anastomosis: An Experimental Study in a Rat Model

Objectives:

Ankaferd BloodStopper (ABS) is a topical hemostatic agent that modulates the inflammatory response and accelerates wound healing. The aim of this study was to determine the effects of ABS on the colon anastomosis wound healing in a rat model.

Methods:

Thirty-two Wistar albino rats were divided into four groups as follows: Group A (n=8), left colonic anastomosis plus ABS treatment (sacrificed on the 3^rd day); Group B (n=8) (control), left colonic anastomosis (sacrificed on the 3^rd day); Group C (n=8), left colonic anastomosis plus ABS treatment (sacrificed on the 7^th day); and Group D (n=8) (control), left colonic anastomosis (sacrificed on the 7^th day). All rats were sacrificed at the end of the experiment to assess the anastomosis integrity and the presence of perianastomosis abscesses, peritonitis, and adhesions. Additionally, the bursting pressure and hydroxyproline (OH-pyroline) levels were determined, and a histopathologic evaluation of the perianastomosis tissue was conducted.

Results:

The mean bursting pressure on Day 7 was significantly higher than that on Day 3 in the ABS group (p=0.017). Overall, the bursting pressure was higher in animals treated with ABS than in the control animals, although the difference was not statistically significant. The OH-pyroline levels of both ABS groups were significantly higher than in the control groups. The mean OH-pyroline level on Day 7 was higher than that on Day 3 in the ABS-treated animals (p=0.038).

Conclusion:

ABS increases collagen formation and neovascularization, and it has a positive impact during the colon anastomosis healing in an experimental model of wound healing.