Comparison of healing after cystotomy and repair with fibrin glue and sutured closure in the porcine model

Novel synthetic adhesive as an effective alternative to Fibrin based adhesives

AIM

To compare a novel, fully synthetic, polyurethane based glue (MAR-1) to fibrin sealant in a partial liver resection rat model.

METHODS

After 50% resection of the lateral left liver lobe in male Wistar rats (n = 7/group/time point), MAR-1, Fibrin or NaCl was applied. After 14, 21 and 90 postoperative days, sealant degradation, intra-abdominal adhesions were scored, and histological examination of liver tissue was performed.

RESULTS

(Mean ± SEM) (MAR-1 vs Fibrin vs NaCl). Bleeding mass was significantly higher in NaCl (3.36 ± 0.51 g) compared to MAR-1 (1.44 ± 0.40 g) and Fibrin (1.16 ± 0.32 g). At 14 and 90 d, bleeding time was significantly lower in MAR-1 (6.00 ± 0.9 s; 13.57 ± 3.22 s) and Fibrin (3.00 ± 0.44 s; 22.2 ± 9.75 s) compared to NaCl (158.16 ± 11.36 s; 127.5 ± 23.3 s). ALT levels were significantly higher in MAR-1 (27.66 ± 1 U/L) compared to Fibrin (24.16 ± 0.98 U/L) and NaCl (23.85 ± 0.80 U/L). Intrabdominal adhesions were significantly lower in MAR-1 (11.22% ± 5.5%) compared to NaCl (58.57% ± 11.83%). Degradation of the glue was observed and MAR-1 showed almost no traces of glue in the abdominal cavity as compared to the Fibrin (10% ± 5% 14 d; 7% ± 3% 21 d). Survival showed no significant differences between the groups.

CONCLUSION

Compared to Fibrin, MAR-1 showed similar hemostatic properties, no adverse effects, and is biocompatible. Further studies on adhesion strength and biodegradability of synthetic sealants are warranted.

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.

Regulatory challenges for autologous tissue engineered products on their way from bench to bedside in Europe

Since the late eighties of last century the high potential of tissue engineered products (TEP)s has been shown for the treatment of various diseases and many scientific publications appeared in this field. However, only few products reached the market since. Development of TEPs is a promising but owing to its novelty a very challenging task that requires experts in this still developing field as well as ample financial resources. This paper summarises relevant regulatory challenges during quality, preclinical and clinical development of autologous TEPs in Europe. Selected strategies on how to manage major issues are presented, together with some examples from the development of an autologous TEP for urethroplasty. Considering these aspects may help other investigators with potential strategies during the development of novel TEPs.

Comparison of laparoscopic closure of the bladder with barbed polyglyconate versus polyglactin suture material in the pig bladder model: an experimental in vitro study

PURPOSE

The objective of this randomized in-vitro study was to compare the suturation time, integrity, and quality of the bladder closure in fresh cadaver pig bladders performed with barbed polyglyconate sutures vs polyglactin 910 sutures in running and interrupted fashion.

MATERIALS AND METHODS

Forty-eight pig bladders, each weighing from 120 to 150 g, were randomly divided into three groups: Group 1 (interrupted polyglactin 910 suture group), group 2 (running polyglactin 910 suture group), and group 3 (running barbed polyglyconate suture group). The bladder defects were closed laparoscopically, and the suturation times were noted. Two surgeons evaluated the integrity of each bladder closure. A cystometry was performed, and the filling and leak pressures were noted. A Kruskal-Wallis variance analysis test was used to compare the results of the three groups, and P<0.05 was considered significant.

RESULTS

There was a statistically significant difference between the mean suturation times of three groups: Group 1, 15.2 minutes; group 2, 9.14 minutes; and group 3, 7.13 minutes (P<0.05). Mean bladder capacity at the time of leakage was 276.2, 353.8, and 419.7 mL for groups 1, 2, and 3, respectively, and the difference was statistically significant (P<0.05).

CONCLUSION

For the first time, we demonstrated laparoscopic knotless closure of bladder defects using the barbed polyglyconate suture material in an experimental in-vitro model. Closing the pig bladder with running knotless barbed suture provides a more effective and faster watertight bladder closure than traditional polyglactin 910 suture material.

Laparoscopic cystotomy for removal of a large bladder polyp in a juvenile alpaca with polypoid cystitis

OBJECTIVE

To describe a method for laparoscopic cystotomy in an alpaca.

STUDY DESIGN

Case report.

ANIMALS

Female alpaca.

METHODS

An 8-month-old female alpaca was admitted with a 6-week history of straining to urinate and vulvar swelling. Transrectal ultrasound examination revealed a 1.5 x 1.5 x 2 cm polyp within the bladder.

RESULTS

The mass was excised using laparoscopic cystotomy. Leakage from the cystotomy site resolved over 12 days using a Foley catheter. The alpaca was healthy and urinating normally at 9 months after surgery.

CONCLUSION

Minimally invasive surgery by laparoscopic cystotomy can be used to remove large urinary polyps in alpacas.

CLINICAL RELEVANCE

Urinary bladder polyps should be considered as differential diagnosis in alpacas with stranguria.

Evaluation of the outcomes of electrosurgical induced bowel injury treated with tissue glue/sealant versus sutured repair in a rabbit model

INTRODUCTION

Bowel injury is an uncommon, although potentially devastating, intraoperative laparoscopic complication. Questions have been raised about the possible use of a tissue adhesive to repair injured bowel. We compared glued repair and sutured repair of both large bowel (LB) and small bowel (SB) electrosurgical injuries in a rabbit model.

METHODS

Pneumoperitoneum was obtained, and four laparoscopic ports were placed in each of 48 New Zealand rabbits. The hook electrode was used in a specified manner to create an equal number of uniform full-thickness injuries to either the SB or the LB. Laparoscopic repair was performed with a 3-0 silk Lembert suture (LS), fibrin glue (FG), or BioGlue (BG), or repair was not performed (i.e., no repair, NR); the animals were monitored for 3 weeks. Adverse clinical outcomes and findings at laparotomy were recorded. Pathologic assessment included an objective scaled evaluation of the intensity of the inflammatory response and degree of healing.

RESULTS

In the SB injury group, deteriorating clinical condition necessitated early euthanasia in one animal repaired with FG, one animal repaired with BG, and two animals with NR. LS repair animals had no adverse clinical outcomes. The LB injury group had no adverse clinical outcomes regardless of the method of repair, including the control group. Of the animals that survived for 3 weeks, the animals repaired with BG had more intraabdominal adhesions (100%) than LS (33%), FG (55%), and NR (50%) (p = 0.001). The pathologic assessment revealed that BG induced a more intense inflammatory response (p < 0.05).

CONCLUSION

In the rabbit, suture repair of an electrosurgical SB injury appears to have improved outcomes when compared with a glued repair. In contrast, LB injury responded well to any form of treatment. The data suggest that suture is superior to biological glues when dealing with a laparoscopic electrosurgical bowel injury.