The use of cyanoacrylate in surgical anastomosis: an alternative to microsurgery

One-Step Protocol for the Synthesis of Cyanoacrylates Promoted by Elemental Sulfur from p-Quinone Methides and Cyanoacetates under Basic Conditions

Cyanoacrylates have a wide range of biological activities and are extensively applied in production and daily life. Classic synthetic routes to cyanoacrylates have many limitations. Herein, we demonstrate an elemental sulfur-promoted method for the synthesis of β,β-diaryl cyanoacrylates by a tandem 1,6-Michael addition/oxidation/elimination process from p-QMs and cyanoacetates under optimal conditions. The effective protocol has good substrate scopes and yields, and the ratio of inseparable E/Z isomers of cyanoacrylates is also determined by 1HNMR.

Colonic Anastomoses Reinforced With Ethyl-2-Cyanoacrylate Compared With Polydioxanone Sutures Alone in Fecal Peritonitis: An Experimental Study in Wistar Rats

INTRODUCTION

The use of tissue adhesives has been proposed as an anastomosis reinforcement; however, their efficacy has not been evaluated in a contaminated environment. The objective of this study was to determine if the use of sutures reinforced with ethyl-2-cyanoacrylate for colonic anastomoses in the presence of fecal peritonitis, in a murine animal model, decreases the frequency of dehiscence.

METHODS

Wistar rats were used. Fecal peritonitis was established until reaching 18 hours of evolution. Then, resection and anastomosis of the colon were performed with only polydioxanone (PDS) sutures in the control group and reinforcement with ethyl-2-cyanoacrylate in the experimental group. The dehiscence frequency and burst pressure were evaluated six days after the anastomosis was performed.

RESULTS

We included 30 Wistar rats, all males, with a median age of five months and an average weight of 350.43 g. Anastomotic dehiscence was observed in 53.33% of the control group, in contrast with 13.33% of the experimental group (p = 0.020). There was no significant difference in burst pressure between the two groups.

CONCLUSION

The use of ethyl-2-cyanoacrylate, in an experimental murine animal model, as reinforcement in colonic anastomoses in the presence of fecal peritonitis decreases the frequency of anastomotic dehiscence, although it does not increase resistance to burst pressure.

Antimicrobial Activity and Cytotoxicity of Prepolymer Allyl 2-cyanoacrylate and 2-Octyl Cyanoacrylate Mixture Adhesives for Topical Wound Closure

The development of a new skin adhesive that can be used inside and outside the body, which prevents infection and has fewer scars and less side effects, is currently attracting attention from the scientific community. To improve biocompatibility, prepolymer allyl 2-cyanoacrylate (PAC) and 2-octyl cyanoacrylate (OC) were mixed in various proportions and tested for their therapeutic potential as skin adhesives. A series of skin adhesive samples prepared by mixing PAC, OC, and additives with % (w/w) ratios of 100:0:0, 0:100:0, 70:0:30, 40:30:30, and 30:40:30 were tested to determine their antimicrobial activity, cell cytotoxicity, and formaldehyde release. The additives include myristic acid and dibutyl sebacate as plasticizers and butylated hydroxyanisole as an antioxidant. It was observed that the samples containing 70% PAC (PAC7) or 40% PAC (PAC4) with 30% additives had the highest antimicrobial activities against various microbial cells and no cytotoxicity regarding in vitro fibroblast cell growth. In addition, these formulations of adhesive samples released formaldehyde within the levels permitted for medical devices. Taken together, the mixture of PAC and OC as a topical skin adhesive for wound closure was found to be biocompatible, mechanically stable and safe, as well as effective for wound healing.

Stereoselective synthesis of vinyl nitriles through a Ramberg-Bäcklund approach

The applicability of vinyl nitriles in the preparation of pharmaceuticals, polymers, and other valuable materials benefits from robust preparative methodologies. In this work, we present a novel approach for the synthesis of vinyl nitriles based on the Ramberg-Bäcklund olefination reaction (RBR). While there are few examples for accessing functionalized olefins using the RBR, we believe that this methodology embodies useful means for installing privileged vinylnitrile building blocks, such as the acrylonitrile fragment of the US FDA-approved antiviral rilpivirine.

S S, Durairaj D, Rajasekaran MA, Rajiah D. Application of N-Butyl-2-Cyanoacrylate for the Treatment of Comminuted Fractures in the Anterior Wall of the Maxillary Sinus: A Prospective Clinical Study

Objective The purpose of the study was to assess the clinical outcome of patients by using n-butyl-2-cyanoacrylate in the management of comminuted fracture segments of the anterior wall of the maxillary sinus in the zygomatico-maxillo-facial complex region. Material and methods A prospective study was done at a tertiary care teaching institute in India with a study population of ten patients in a single group. The method of recruitment was a convenient sampling method. Out of all the study subjects, three patients had isolated maxillary sinus wall fractures, whereas the remaining seven had other associated facial fractures that required stable fixation with mini plates. The comminuted fractures of the anterior wall of the maxillary sinus were carefully reduced through an intra-oral approach, and n-butyl-2-cyanoacrylate was applied over the edges of fractured segments. The segments were left undisturbed for one minute and closed with a 3-0 vicryl. The outcome variables, namely bone alignment visualised through computed tomography (CT) scan postoperatively, paresthesia or hypoesthesia of the infraorbital nerve, postoperative infection, and wound dehiscence, were noted at one-week, one-month, three-month, and six-month intervals. Data were analysed using the Chi-square test. Results Among all patients, seven had satisfactory bone alignment. A total of seven patients recovered from hypoesthesia of the infraorbital nerve. The association of bone alignment with hypoesthesia or paresthesia revealed a highly significant p-value (0.002) using the Chi-square test. Also, an association between postoperative infection and wound dehiscence showed substantial results with a p-value less than 0.05. Conclusion Good bone alignment was seen postoperatively in 70% of patients. The cyanoacrylate used had no adverse reactions, and its application was restricted to non-load-bearing areas in this study. Further studies with a higher level of evidence and a larger sample size are needed to validate the use of adhesives for bone fixation in other regions of the face.

Reduction of Anastomotic Time Through the Use of Cyanoacrylate in Microvascular Procedures

Background: Ever since the description of the first microvascular anastomosis, numerous alternative methods have been described to the classical approach. Tissue adhesive has shown promising result in previous studies and can be a fast and efficient alternative which still requires more studies to allow its clinical implementation. Methods: A randomized comparative experimental study was conducted on rats' femoral arteries and an end-to-end anastomosis was performed in order to compare 2 anastomosis techniques. In one group, a simple interrupted suture was utilized, whereas in the second group a combination between fewer sutures and tissue adhesive was used. The anastomotic time, total operative time, blood flow velocity before, immediately after and 48 hours after the procedure, as well as an independent grading of the anastomosis immediately after the procedure were performed. Magnetic resonance imaging (MRI) was performed in order to assess the degree of stenosis. After euthanasia, histology and scanning electron microscopy (SEM) were performed on the vessels in order to assess possible complications. Results: A total of 24 anastomoses were performed, of which 12 with a classic technique and 12 with an adhesive technique. All the anastomoses were patent with a significant reduction of anastomotic and total operative time. The grading of the anastomoses showed better results in the classic suture group. The blood flow velocities were not statistically significant between the 2 groups. On MRI there was one stenotic anastomosis, whereas histology and SEM showed more complications on the adhesive group. Conclusion: Anastomotic times were significantly lower with a non-significant trend toward more thrombotic complications in the adhesive group. Further improvement of the glue properties and refinement of the technique will likely make it a viable alternative to interrupted suturing in the future.

A surgical method for continuous intraportal infusion of gut microbial metabolites in mice

Gut microbe-derived metabolites influence human physiology and disease. However, establishing mechanistic links between gut microbial metabolites and disease pathogenesis in animal models remains challenging. The major route of absorption for microbe-derived small molecules is venous drainage via the portal vein to the liver. In the event of presystemic hepatic metabolism, the route of metabolite administration becomes critical. To our knowledge, we describe here a novel portal vein cannulation technique using a s.c. implanted osmotic pump to achieve continuous portal vein infusion in mice. We first administered the microbial metabolite trimethylamine (TMA) over 4 weeks, during which increased peripheral plasma levels of TMA and its host liver-derived cometabolite, trimethylamine-N-oxide, were observed when compared with a vehicle control. Next, 4-hydroxyphenylacetic acid (4-HPAA), a microbial metabolite that undergoes extensive presystemic hepatic metabolism, was administered intraportally to examine effects on hepatic gene expression. As expected, hepatic levels of 4-HPAA were elevated when compared with the control group while peripheral plasma 4-HPAA levels remained the same. Moreover, significant changes in the hepatic transcriptome were revealed by an unbiased RNA-Seq approach. Collectively, to our knowledge this work describes a novel method for administering gut microbe-derived metabolites via the portal vein, mimicking their physiologic delivery in vivo.

Polymeric Tissue Adhesives

Polymeric tissue adhesives provide versatile materials for wound management and are widely used in a variety of medical settings ranging from minor to life-threatening tissue injuries. Compared to the traditional methods of wound closure (i.e., suturing and stapling), they are relatively easy to use, enable rapid application, and introduce minimal tissue damage. Furthermore, they can act as hemostats to control bleeding and provide a tissue-healing environment at the wound site. Despite their numerous current applications, tissue adhesives still face several limitations and unresolved challenges (e.g., weak adhesion strength and poor mechanical properties) that limit their use, leaving ample room for future improvements. Successful development of next-generation adhesives will likely require a holistic understanding of the chemical and physical properties of the tissue-adhesive interface, fundamental mechanisms of tissue adhesion, and requirements for specific clinical applications. In this review, we discuss a set of rational guidelines for design of adhesives, recent progress in the field along with examples of commercially available adhesives and those under development, tissue-specific considerations, and finally potential functions for future adhesives. Advances in tissue adhesives will open new avenues for wound care and potentially provide potent therapeutics for various medical applications.

The management of esophago-gastric necrosis due to caustics ingestion: Anastomotic reinforcement with Cyanoacrylate glue and damage control with Vacuum Assisted Closure Therapy-A case report

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Optimal timing to treat esophago-gastric necrosis due to caustic ingestion.

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Proposal of three steps approach to manage esophago-gastric necrosis.

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Use of Cyanoacrylate glue to reinforce anastomosis.

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Vacuum Assisted Closure for damage control after surgery.

Introduction

The surgical treatment of a complete gastric necrosis due to caustic ingestion is extremely challenging and life threatening. In this emergency scenario, a first-time reconstruction of the gastrointestinal tract is often dangerous for the patient because of the high risk of infections and anastomosis leakage. Literature lacks of clear indications for the management of this condition.

Presentation of case

Male patient with history of major depression disorder was admitted to our Emergency Unit after the ingestion of muriatic acid. CT scan showed massive pneumo-peritoneum with esophago-gastric thickening. Free fluids in the abdominal cavity were detected. Intraoperative finding was a complete necrosis of the stomach and corrosion of the lower esophagus.

Discussion

In this case report we proposed a first approach with the drainage and lavage of the abdomen cavity. Then, an esophago-jejunum anastomosis reinforced by Cyanoacrylate glue was performed and a damage control with VAC therapy (Vacuum Assisted Closure) was carried out.

Conclusion

Cyanoacrylate glue could be considered useful and efficient in the reinforcement of anastomosis even in emergency surgical procedures. Damage control using VAC allows to keep a good control of the surgery performed.

Clinical Feasibility of Large Gastrotomy Closure Using a Flexible Tissue Glue Based on N-Butyl-2-Cyanoacrylate: Experimental Study in Pigs

BACKGROUND

The use of synthetic adhesives such as cyanoacrylates has been established previously for a wide range of clinical indications. However, more research is necessary to evaluate their use in digestive closures or anastomosis. New chemical formulations developed to achieve more flexibility of synthetic adhesives (i.e., based on n-butyl-2-cyanoacrylate) could be an alternative to achieve this purpose. The aim of this study was to investigate the feasibility of using flexible cyanoacrylate adhesives for large gastric incision closure in an animal model.

METHODS

Twelve farm pigs were divided in two groups depending on the type of closure method applied. In all cases, extra-large seven centimeters gastrostomies were performed. Braided absorbable hand-sewn interrupted suture versus n-butyl-2-cyanoacrylate with softener closure were compared during a 3-week follow-up period. Histopathological aspects, hematologic and inflammatory biomarkers, and endoluminal pressure tolerated until leakage were assessed. The time spent on both closing procedures was compared.

RESULTS

No differences between the two groups were found in any of the histopathological and inflammatory variables evaluated. The glued group tolerated a significantly higher pressure than the manual suture group. A reduction of surgery time was also observed.

CONCLUSIONS

Our results suggest that flexible cyanoacrylates could be a feasible alternative to improve the clinical outcome of the closure of hollow viscera through more efficient sutureless procedures.

Cytocompatibility and mechanical properties of surgical sealants for cardiovascular applications

OBJECTIVES

The present study compared physical, mechanical, and biologic characteristics of 4 clinically available surgical sealants for cardiovascular repair.

METHODS

BioGlue (Cryolife Inc, Kennesaw, Ga), PreveLeak (Mallinckrodt Pharmaceuticals, St Louis, Mo), Tridyne VS (BD, Franklin Lakes, NJ), and Coseal (Baxter Healthcare Corporation, Westlake Village, Calif) were compared for the following properties: hydrated swelling, cytocompatibility, burst strength, biaxial stretching (elasticity), and in vitro degradation.

RESULTS

Sealants showed a wide range of swelling upon hydration. By gravimetric and volumetric measurement, swelling was greatest for Coseal followed by Tridyne VS, BioGlue, and PreveLeak. Tridyne VS was the most cytocompatible based on Alamar Blue assay results, supporting 85% cell survival compared with 36% to 39% survival with the other sealants. All sealants withstood pressure above mean arterial pressure (70-110 mm Hg) and physiologic systolic blood pressure (90-140 mm Hg) in an ex vivo arterial flow burst model; lowest peak pressure at failure was PreveLeak at 235 ± 48 mm Hg, and highest peak pressure at failure was BioGlue at 596 ± 72 mm Hg. Biaxial tensile testing showed no differences in elasticity between ex vivo porcine aorta and carotid arteries and Tridyne VS or Coseal, and BioGlue and PreveLeak were significantly stiffer. In vitro degradation time for Coseal was 6 days and 21 days for Tridyne VS. No degradation was observed in BioGlue or PreveLeak for 30 days.

CONCLUSIONS

Although all sealants withstood supraphysiologic arterial pressure, there were differences in characteristics that may be important in clinical outcome. Coseal degradation time was short compared with other sealants, whereas BioGlue and PreveLeak showed a significant compliance mismatch with native porcine carotid artery. Tridyne VS was significantly more cytocompatible than the other 3 sealants.

2-Octylcyanoacrylate for the prevention of anastomotic leak

BACKGROUND

Anastomotic leak after colorectal surgery is a significant cause of morbidity and mortality. The aim of this study was to evaluate the impact of a reinforced colo-colonic anastomosis with tissue adhesive, 2-octylcyanoacrylate (2-OCA), on the integrity of anastomotic healing as measured by anastomotic bursting pressure.

METHODS

Sixty-eight female Sprague-Dawley rats underwent a rectosigmoid colon transection and a sutured end-to-end anastomosis followed by randomization to receive no further intervention or reinforcement with the tissue adhesive, 2-OCA. After seven postoperative days, a macroscopic assessment of the anastomosis, mechanical assessment to determine anastomotic bursting pressure, and a detailed semi-quantitative histopathologic healing assessment were performed.

RESULTS

Thirty-four animals were randomized to each group. Study characteristics did not differ between the groups. There was also no difference in the degree of adhesions present postoperatively. Although there was no difference between the net proximal and distal luminal areas in the two groups (0.37 cm²versus 0.55 cm², P = 0.26), the 2-OCA group exhibited evidence of stricture in 15% of anastomoses as compared with 3% in the suture-only group (P < 0.0001). Histologically, the presence of only fibroblasts density was statistically more evident in the 2-OCA group compared with the sutured-only anastomosis (P = 0.0183). There was not a significant increase in mechanical strength in the 2-OCA group (238.9 mm Hg) versus in the suture-only group (231.8 mm Hg). There was no difference in the rate of anastomotic leak in the 2-OCA as compared with the suture-only group (9.1 versus 8.8%).

CONCLUSIONS

Application of 2-OCA to reinforce a colo-colonic anastomosis clinically provides no benefit to its mechanical strength and detrimentally increases the rate of obstruction and/or stricture in this in vivo model.

Behaviour of the Biological Adhesives TachoSil®, GelitaSpon®, and a New Elastic Cyanoacrylate (Adhflex®) in Experimental Renal Trauma and Wound Healing

BACKGROUND

Renal injuries are relatively frequent in abdominal trauma. In some cases, adhesives and sealants can be used to repair and preserve injured organs. This paper describes the behaviour of three biomaterials - TachoSil®, GelitaSpon®, and a new elastic cyanoacrylate (CyA), Adhflex® - in standardized experimental renal injuries.

METHODS

Ninety male Wistar rats (300-350 g) were used. A Stiefel Biopsy Punch (8 mm diameter, 3 mm depth) was used to create injuries to the anterior kidney to evaluate wound healing. The animals were divided into five groups: (1) sham (n = 3); (2) control (n = 6), untreated, standard punch injury created on the anterior left kidney; (3) TachoSil® (n = 27), punch injury treated with TachoSil®; (4) GelitaSpon® (n = 27), punch injury treated with GelitaSpon®, and (5) Adhflex® (n = 27), punch injury treated with the new elastic CyA adhesive. The parameters studied were bleeding time, peritoneal adhesions, and histopathological evaluation of wound healing on days 2, 6, and 18, including measurements of the gap between wound edges, inflammatory reaction (CD68), and vascular neoformation (CD31).

RESULTS

The bleeding time was significantly shorter (27.7 ± 12.9 s) in the Adhflex® group than in the control (135.8 ± 11.6 s; p < 0.01), TachoSil® (77.5 ± 7.4 s; p < 0.05), and GelitaSpon® (82.5 ± 14.4 s; p < 0.05) groups. The incidence of intraperitoneal adhesions in the animals treated with Adhflex® was 3.6 times higher than in the non-treated group. It was also higher (p < 0.04) than in the groups treated with TachoSil® and GelitaSpon®. The time point with the largest gap between the wound edges and most abundant granulation tissue was at day 6. The largest gap after 18 days was reported for the Adhflex® adhesive. With regard to the markers CD31 and CD68, Adhflex® showed the largest areas 2 days after surgery, but no differences were found after 6 and 18 days versus the other treatments. The expression of the immunomarkers on the renal samples treated with Adhflex® was consistent with a normal healing process.

CONCLUSIONS

In this experimental model of renal injuries, the new elastic CyA (Adhflex®) resulted in the shortest bleeding time. It offers rapid sealing of the bleeding produced by renal injuries, fixation to adjacent tissues, and reduced occurrences of relapse. The evolution of the scarring is similar to other procedures. Given that traumatic renal injuries are always an emergency due to haemorrhage, Adhflex® might offer additional benefits over conventional treatment methods in human clinical practice.

Adhesive and sealant interfaces for general surgery applications

The main functions of biological adhesives and sealants are to repair injured tissues, reinforce surgical wounds, or even replace common suturing techniques. In general surgery, adhesives must match several requirements taking into account clinical needs, biological effects, and material features; these requirements can be fulfilled by specific polymers. Natural or synthetic polymeric materials can be employed to generate three-dimensional networks that physically or chemically bind to the target tissues and act as hemostats, sealants, or adhesives. Among them, fibrin, gelatin, dextran, chitosan, cyanoacrylates, polyethylene glycol, and polyurethanes are the most important components of these interfaces; various aspects regarding their adhesion mechanisms, mechanical performance, and resistance to body fluids should be taken into account to choose the most suitable formulation for the target application. This review aims to describe the main adhesives and sealant materials for general surgery applications developed in the past decades and to highlight the most important aspects for the development of future formulations.

Deliberate self-harming application of superglue in the nose: case report and literature review

BACKGROUND

Accidental and non-accidental applications of superglue in the ear, nose and oral cavity have been reported previously. Surgical removal of glue from the nose is the current practice.

CASE REPORT

This paper reports the case of an 18-year-old female, who presented with complete bilateral nasal occlusion due to deliberate self-application of superglue in both nostrils to avoid nasogastric tube insertion.

RESULTS

Removal of glue was accomplished with a combination of local anaesthetic cream and acetone-soaked cotton buds, which caused only minimal discomfort to the patient. All traces of glue disappeared within 10 days, without causing damage to the nasal mucosa, nasal blockage or pain.

CONCLUSION

To the best of our knowledge, this is the first case report of deliberate self-application of superglue in the nose. A successful non-surgical management option for the removal of glue from the nose is introduced.