Sutureless intestinal anastomoses

Protective effects of thymoquinone on the healing process of experimental left colonic anastomosis

PURPOSE

Colorectal cancer is globally the third most common cancer. Anastomotic complications remain to be an important issue for colorectal surgery. The aim of this study was to investigate the protective effects of thymoquinone (TQ) on the healing process of left colonic anastomosis in an experimental model.

METHODS

Thirty-two male rats were divided into two groups, as the TQ group and the control group. TQ was administered to the TQ group, whereas the control group was given a standard feed and water for 2 wk. Following the creation of a left colonic anastomosis, subjects in both groups were sacrificed on the postoperative (PO) third and seventh days. Anastomotic burst pressures were measured mechanically. Immunohistochemical stainings for proliferating cell nuclear antigen, cluster of differentiation (CD) 31, CD45 were performed, and the matrix metalloproteinase-2 levels were measured. Histologic total scores were calculated according to Ehrlich-Hunt model. A value of P < 0.05 was considered as statistically significant.

RESULTS

One rat in the control group that died on the PO fourth day was excluded. Anastomotic burst pressures on the PO seventh day were higher in the TQ group than the control group (P < 0.01). Histopathological total scores on the PO third and seventh days were higher in the TQ group (P < 0.01). In addition, the TQ group revealed lower matrix metalloproteinase-2 scores on the PO third day and higher hydroxyproline levels on the PO seventh day (P < 0.05 and P < 0.01, respectively).

CONCLUSIONS

The use of TQ in colorectal surgery cases with left-sided colonic anastomosis resulted with increased anastomotic burst pressures and increased tissue hydroxyproline levels.

High-frequency electric welding: a novel method for improved immediate chorioretinal adhesion in vitreoretinal surgery

PURPOSE

To evaluate high-frequency electric welding (HFEW) as a novel technique for retinopexy with improved immediate chorioretinal adhesion

METHODS

In a prospective, randomized, experimental study, we examined 104 eyes of 52 rabbits randomly assigned to either standard 810 nm endolaser retinopexy, alternating current 14-16 V or 18-20 V HFEW retinopexy. A full-thickness fragment of eye wall tissue containing the retinopexy was isolated 1 h, 3 days, 1 week, or 1 month respectively after the intervention, and fixed to an analytical electronic scale. A nylon suture passed through the retina was elevated by a biomechanical force elongation tester. The reduction in weight at the time of retinopexy rupture was registered as a measure for retinopexy adhesion strength.

RESULTS

One hour post-exposure, adhesive strengths were significantly higher in both HFEW groups than in controls (212 ± 26.6 mg and 122 ± 16 mg vs 104 ± 10 mg; p = 0.0001 and p = 0.024 respectively) while laser retinopexy did not significantly change adhesive strength (114 ± 14.0 mg, p = 0.149). Subsequent adhesive strengths were significantly increased for all retinopexy techniques: 3 days post-op 14-16 V HFEW 224 ± 30.0 mg (p = 0.001), 18-20 V HFEW 128 ± 15.6 (p = 0.001), laser 131 ± 12.7 mg (p = 0.0007); at 1 week 14-16 HFEW 235 ± 24.7 mg, 18-20 V HFEW 213 ± 22.4 mg, laser 188 ± 18.7 mg (all p ≤ 0.001); 1 month post-op 14-16 V HFEW 275 ± 32.0 mg, 18-20 V HFEW 283 ± 31.0 mg, laser 276 ± 21.7 mg, rspectively (all p ≤  0.0001).

CONCLUSION

HFEW represents a novel technique for retinopexy during vitreoretinal surgery. It allows firm chorioretinal adhesion immediately after exposure. In non-vitrectomized eyes, using 14-16 V is particularly effective.

Sutureless jejuno-jejunal anastomosis in gastric cancer patients: a comparison with handsewn procedure in a single institute

BACKGROUND

The biofragmentable anastomotic ring has been used to this day for various types of anastomosis in the gastrointestinal tract, but it has not yet achieved widespread acceptance among surgeons. The purpose of this retrospective study is to compare surgical outcomes of sutureless with suture method of Roux-and-Y jejunojejunostomy in patients with gastric cancer.

METHODS

Two groups of patients were obtained based on anastomosis technique (sutureless group versus hand sewn group): perioperative outcomes were recorded for every patient.

RESULTS

The mean time spent to complete a sutureless anastomosis was 11 ± 4 min, whereas the time spent to perform hand sewn anastomosis was 23 ± 7 min. Estimated intraoperative blood loss was 178 ± 32 ml in the sutureless group and 182 ± 23 ml in the suture-method group with no significant differences. No complications were registered related to enteroanastomosis. Intraoperative mortality was none for both groups.

CONCLUSIONS

The Biofragmentable Anastomotic Ring offers a safe and time-saving method for the jejuno-jejunal anastomosis in gastric cancer surgery, and for this purpose the ring has been approved as a standard method in our clinic. Nevertheless currently there are few studies on upper gastrointestinal sutureless anastomoses and this could be the reason for the low uptake of this device.

Compression anastomoses in colorectal surgery: a review

The main serious risks of anastomotic construction in the colon and rectum include dehiscence and stricture formation. There is a resurgence of interest in sutureless anastomoses formed by compression elements since the introduction of shape memory alloy (SMA) systems, which evoke minimal early inflammatory response whilst maintaining anastomotic integrity. Currently, the most commonly used SMA is the nickel-titanium (NiTi) alloy that is highly biocompatible, returning to its pre-deformed stable (austenite) shape under different mechanical and thermal loads for use in humans. Pre-clinical data for shape memory alloy systems in colorectal anastomoses are limited, but it appears to be safe in porcine and canine models with limited leakage and reduced stricture formation. There does not appear to be any difference in tissue biochemistry of inflammatory markers when compared with conventional stapled techniques, although the few studies available show a markedly reduced early inflammatory response at the anastomotic site with the NiTi device. The majority of the clinical data concerning compression anastomoses are derived from the biofragmentable anastomotic ring device. This device has fallen out of use because of reported leaks, instrumental failure and problems with device expulsion. A novel SMA device, the NiTi anastomotic ring, permits construction of a low rectal anastomosis construction during open or laparoscopic procedures. The preliminary data demonstrate a safety comparable to conventional staple technology. This device also provides the potential of benefit of reduced anastomotic inflammation, because the compression ring results in direct serosa-to-serosa (or alternatively serosa-to-muscularis propria) apposition without the persistence of residual foreign material. This type of construction could lead to a reduced incidence of early anastomotic leakage and/or the development of anastomotic stenosis. Randomized clinical trials employing a NiTi arm for elective, emergency and high-risk colorectal anastomoses are required to determine its indications and clinical profile as well as to assess whether such technology may selectively obviate the need for proximal diversion in low colorectal anastomoses.

Compression anastomoses in colon and rectal surgery with the NiTi ColonRing™

BACKGROUND

The aim of this prospective study was to evaluate safety and efficacy of the NiTi ColonRing™ for anastomoses on the colon or rectum.

METHODS

During the period September 2008-June 2011, anastomosis using the NiTi ColonRing™ was scheduled to be performed on 60 patients (36 females, 24 males/mean aged 67 years), 53 of whom underwent colectomy for cancer and 7 reconstruction after Hartmann's procedure. Application of the device failed in one case due to anatomical reasons. Colorectal resections performed were as follows: Right hemicolectomy (5 patients), left colectomy (2), sigmoidectomy (15) and low anterior resection (31). A follow-up clinic visit after 1 month was planned for all patients. Ten patients among the first 14 had rectosigmoidoscopy at 2-3 months. All cancer patients were scheduled for colonoscopy at 12 months.

RESULTS

No intraoperative or postoperative bleeding related to the anastomotic technique was recorded. Median hospital stay after surgery was 10.2 days (9-22 days). One patient died on day 13 due to myocardial infarction. Clinically apparent leak was detected in one patient who had undergone reconstruction after Hartmann; the only treatment required was total parenteral nutrition for 12 days. Anastomotic stenosis occurred in another one patient who had undergone reconstruction after Hartmann; it was easily resolved by balloon dilatation. Mild complications were encountered in 23 other patients (39%). Oral feeding started after day 4. Anastomotic rings were expelled naturally within 7-17 days (mean, 9.2 days). A satisfactory anastomosis was revealed in patients examined colonoscopically at 2-3 and 12 months. Mean follow-up was 15.2 months (2-33 months).

CONCLUSIONS

NiTi ColonRing™ is reliable, safe and efficacious for large bowel anastomoses.

Evaluation of the NiTi Shape Memory BioDynamix ColonRing™ in colorectal anastomosis: first in human multi-center study

BACKGROUND

Shape-memory compression bowel anastomosis using a nickel and titanium alloy may reduce leak rates and eliminate foreign anastomotic material. Its safety and efficacy had been demonstrated by animal studies. We conducted the first prospective multi-center clinical evaluation of the safety and effectiveness of BioDynamix anastomosis with ColonRing™ for large-bowel end-to-end or side-to-end anastomosis.

MATERIALS AND METHODS

The ColonRing™ was compared to the standard double-stapled colorectal/colocolonic anastomosis. Intraoperative and immediate postoperative and 1- and 3-month postoperative follow-up data were recorded.

RESULTS

Ten study patients (four males, median age 62 years, range 35-75) were compared to 13 demographically matched controls (six males, median age 62 years, range 47-82). Colorectal neoplasia was the most frequent indication for surgery (21/23 patients, 91%). The median anastomotic distance from the anal verge for both groups was 10 cm (6-20 cm). The first postoperative bowel movement was on day 5 ±2.2 (study group) and on day 4 ±1.8 (controls), and the median hospital stay was 8 days (6-14 days) and 7 days (6-13 days), respectively. There were no anastomotic leaks. There were three minor complications in each group, unrelated to the device in the study group. Two patients required transanal digital extraction of the ring which was detached but not expelled (one had a soft anastomotic stricture).

CONCLUSIONS

Our preliminary results in this first study on humans indicate that the safety and efficacy of BioDynamix anastomosis with ColonRing™ in colorectal anastomosis in human is comparable to standard staples technology and warrant larger studies for further validation.

An alternative to conventional hand-sewing colocolic anastomosis: anastomosis with absorbable surgical barrier film without sutures

AIM

As a result of its high morbidity and mortality rates, anastomotic leakage is one of the most feared complications in colorectal surgery. Therefore, this issue is one of the most relevant in colorectal surgery and a lot of work has been conducted to research it. The aim of this experimental study was to compare colocolic anastomosis performed by using absorbable surgical barrier film without suture and conventional anastomosis performed by hand-sewing technique in terms of anastomosis safety.

METHOD

In this study, 40 Norway Wistar Albino 3-month-old female rats were used. Each weighed between 250 and 300g. The rates were divided into two groups, a control group and an experimental group. Full-thickness incisions were made on the ascending colon of both groups of rats. The control group's anastomoses were conducted using a hand-sewn technique consisting of one layer of nonabsorbable sutures (Gambee suture). The experimental group's anastomoses were performed using absorbable surgical barrier film without sutures. Afterwards, sample pieces of the anastomosis area were taken from all rats on either the 3rd or the 7th day following the operation, resulting in subgroups that led to a total of four test groups. The samples taken were subjected first to an anastomosis bursting pressure test followed by histopathological examinations and a test to detect the levels of hydroxyproline in the tissue.

RESULTS

The control groups (groups 1 and 3) had average anastomotic bursting pressures of 33.0±9.49mmHg and 146.0±15.06mmHg respectively, whereas experimental groups (groups 2 and 4) had average anastomotic bursting pressures of 58.0±10.33mmHg and 190.0±25.82mmHg respectively. Mann-Whitney U-test analysis of the bursting pressure values indicates the differences between groups 1 and 2 (3rd day postoperatively) and groups 3 and 4 (7th day postoperatively) to be statistically significant (P=0.0001 and P=0.0003 respectively). Values obtained from histopathological staging conducted according to the Ehrlich-Hunt model where the evaluation criteria in this model are: amount of inflammatory cells, fibroblasts, neovascularization and collagen and which were analysed using the Mann-Whitney U-test have shown no significant difference between 3rd day postoperatively groups 1 and 2 (P=0.579) while the difference between 7th day postoperatively groups 3 and 4 was found to be significant (P=0.023). Average levels of hydroxyproline in the tissue were 88.18±8.04mg/l for group 1, 56.31±5.40mg/l for group 2, 135.0± 6.30mg/l for group 3 and 100.2±15.42mg/l for group 4. Analysis of values in the groups using the Mann-Whitney U-test indicate a significant difference (P < 0.0001) both between groups 1 and 2 and between groups 3 and 4.

CONCLUSION

The use of absorbable surgical barrier film without sutures for colocolic anastomosis in rats may be safe.

Cyanoacrylate for colonic anastomosis; is it safe?

BACKGROUND

This experimental study evaluated the effectiveness and safety of using cyanoacrylate adhesive for sutureless colonic anastomosis and as a protective seal to prevent leakage.

METHODS

Sixty male Sprague-Dawley rats (300 +/- 10 g, 9 weeks old) were divided into three groups: in group I, the anastomosis was sutured in a single layer with 5-0 polypropylene; in group II, the anastomosis was fixed using N-butyl-2-cyanoacrylate (Histoacryl(R)); and in group III, the anastomosis was sutured and then sealed with N-butyl-2-cyanoacrylate. The rats were sacrificed on postoperative day 7. The anastomoses among the three groups were compared by measuring wound infection, anastomotic leakage, anastomotic stricture, adhesion formation, anastomotic bursting pressure, and histological appearance.

RESULTS

No anastomotic leakage was observed in any group. Anastomotic stricture was significantly more extensive in groups II and III (p < 0.001). Bursting pressure was significantly lower in groups II and III (168 +/- 58, 45 +/- 21, and 60 +/- 38 mmHg for groups I to III, respectively, p < 0.001). The severity of inflammatory reactions was significantly greater and collagen deposition was significantly lower in groups II and III (p < 0.05).

CONCLUSIONS

N-butyl-2-cyanoacrylate could be a useful method for sutureless colonic anastomosis based on the absence of anastomotic leakage, but it may impede healing of the colonic anastomosis. In addition, when used to seal sutured colonic anastomoses, cyanoacrylate may have a negative influence on anastomotic healing. The clinical use of N-butyl-2-cyanoacrylate in colonic anastomosis does not appear to be acceptable and safer anastomotic methods or alternative forms of cyanoacrylate should be developed.

Compression anastomosis: history and clinical considerations

BACKGROUND

Despite the fact that the concept of compression anastomosis has been investigated for nearly 2 centuries, it has not yet achieved widespread acceptance. The aim of the current report is to review the literature regarding compression anastomoses.

DATA SOURCES

A multi-database search was conducted using PubMed, Ovid, and the Cochrane Databases (all until June 2007), in addition to electronic links to related articles and references of selected articles. The following terms were used for the search in various combinations: anastomosis, anastomoses, sutureless, compression, nickel-titanium; Nitinol; CAC; CAR; AKA-2, Valtrac biofragmentable anastomotic ring, BAR. Language restrictions were not applied.

CONCLUSIONS

The various methods of compression anastomosis have been shown to be at least comparable to the standard techniques of suturing and stapling. The measurement of outcomes, including cost, safety, and efficacy of treatment, indicated that compression anastomosis can save time, is cost-effective, and offers an acceptable cost/benefit ratio compared to both stapled and sutured anastomoses. However, compression anastomosis did not gain worldwide popularity.

Polypropylene mesh covered colonic anastomosis. Results of a new anastomosis technique

BACKGROUND

The morbidity and mortality rates of anastomosis leakage of the gastrointestinal system, are high. In this study we covered the colonic anastomosis with polypropylene mesh on the safety of the anastomosis was investigated.

METHODS

Twenty female albino rabbits were divided into two groups. First of all, a segmental colon resection was performed in both the groups and a single layer of anastomosis was made. In addition, a polypropylene mesh as long as the circumference of the anastomosis in the study group. All the rabbits were sacrificed on the 10th postoperative day and the explosion pressure of the anastomosis, histopathological investigation of the anastomotic contour, and peritoneal adhesion were compared.

RESULTS

The anastomoses of all the subjects in the control group had exploded and the average explosion pressure was 149 +/- 16 mmHg. However, in the study group, the anastomoses did not explode in nine (90%) of the subjects, whereas it exploded in only one (10%) with a pressure of 260 mmHg. The average explosion pressure in the study group was 315 +/- 30 mmHg (p < 0.0001). No significant difference was established between the groups according to the histopathological classification of the anastomotic contour performed according to the Ehrlich-Hunt model (p > 0.05). Peritoneal adhesions of the groups is not statistically different (p > 0.05).

CONCLUSION

During the short follow-up period, this new technique significantly increased the safety of the anastomosis, moreover it did not cause any increase in peritoneal adhesions. This success has most probably occurred as a result of the external mechanical support to the anastomosis.

Compression anastomosis for Roux-en-Y gastric bypass: observations in a large animal model

BACKGROUND

In the morbidly obese, laparoscopic Roux-en-Y gastric bypass (RYGB) effectively achieves weight loss with the resolution of co-morbidities. The goal is to create a small-volume gastric pouch with a narrow gastrojejunal anastomosis (GJA). The procedure is associated with a GJA stricture rate of approximately 3%. The use of a compression anastomotic device to create a sutureless gastrointestinal anastomosis, replacing sutures or staples, might reduce tissue trauma and improve the GJA patency rate. A temperature-dependent, memory-shape, Nitinol Compression Anastomosis Clip (CAC) has been successfully used in intestinal anastomoses. Compression of the entrapped bowel leads to necrosis, with device expulsion after 7-10 days.

METHODS

We designed a pilot animal model study of open RYGB to examine the clip's safety in the performance of upper gastrointestinal anastomoses. Six 40-kg female pigs underwent RYGB. Group 1 (n = 3) underwent GJA with the CAC and a stapled jejunojejunal anastomosis (JJA). Group 2 (n = 3) underwent GJA and JJA with the CAC. One pig from each group was euthanized at 1, 4, and 8 weeks postoperatively.

RESULTS

Two pigs, one from each group, developed gastroparesis. At autopsy, all anastomoses were patent; the mean GJA diameter with the CAC was 1.6 cm (range 0.6-3), the mean JJA diameter with the stapler was 3.8 cm (range 35-40), and the mean JJA diameter with the CAC was 3 cm (range 3-3.2). Anastomotic burst pressures were similar between the stapled and CAC anastomoses. The device was passed per rectum by postoperative day 9 (range 8-12). Histologic examination of the CAC anastomoses demonstrated a complete mucosal lining with no evidence of stricture formation at 2 months.

CONCLUSION

The results of this small animal study have demonstrated the safety of sutureless compression anastomoses in an animal model of open RYGB.

Sutureless intestinal anastomosis with the biofragmentable anastomosis ring: experience of 632 anastomoses in a single institute

PURPOSE

Uncertainty with the safety of the biofragmentable anastomosis ring makes surgeons hesitate in its widespread use in intestinal surgery. This study was designed to evaluate the validity of the biofragmentable anastomosis ring as a routine anastomotic device in enterocolic surgery.

METHODS

The study analyzed the nine-year experience of 632 biofragmentable anastomosis ring anastomoses performed in 617 patients: 525 (83 percent) as elective procedures and 107 (17 percent) as emergency. Three classic types of anastomosis, end-to-end (n=354), end-to-side (n=263), and side-to-side (n=15), were performed with a standard technique.

RESULTS

Anastomotic sites included ileocolic/ileorectal in 283 patients (45 percent), colorectal in 148 (23 percent), enteroenteric in 101 (16 percent), and colocolic in 100 patients (16 percent). Anastomotic leakage with clinical relevance was observed in five patients (0.8 percent): three elective cases, and two emergency (2 colorectal anastomoses and 1 ileorectal required diversions). Among 13 instances (2.1 percent) with postoperative intestinal obstruction, only 1 required relaparotomy for closed-loop obstruction. Seven patients (1.1 percent; 4 elective cases, and 3 emergency) died postoperatively; no deaths were directly related to the biofragmentable anastomosis ring technique.

CONCLUSIONS

Our data suggest that the anastomosis using the biofragmentable anastomosis ring is a uniform and highly reliable technique even in high-risk emergency surgery. Along with its clinical validities, clinical application of the biofragmentable anastomosis ring in different types of anastomoses in enterocolic surgery is expected to be expanded with a high level of technical safety.

Soft tissue application of lasers

Despite increasing numbers of veterinarians incorporating lasers into their clinical practices, little information has been published about laser clinical applications in soft tissue surgery. This article reviews soft tissue interaction, describes laser equipment and accessories commonly marketed to veterinarians, and discusses clinical applications of the carbon dioxide laser in a systems-based approach. A table of recommended laser tips and settings based on the authors' experiences using a carbon dioxide laser (AccuVet Novapulse LX-20SP, Bothell, WA) is provided.

Intestinal anastomoses detected with a photopolymerized hydrogel

BACKGROUND

This study examines the efficacy of a novel, absorbable photopolymerized hydrogel sealant, Focalseal (Focal Inc, Lexington, Mass), in protecting high-risk suture deficient intestinal anastomoses (HRA) compared with conventional sutured anastomoses (CSA).

METHODS

Twenty-four New Zealand white rabbits were either randomized to small bowel HRA constructed with 4 interrupted 5/0 polyglyconate sutures and treated with Focalseal or small bowel CSA constructed with 8 to 10 interrupted 5/0 polyglyconate sutures. Four rabbits from each group were killed at postoperative days 3, 7, and 21. Anastomoses were assessed for evidence of dehiscence, adhesion formation, stenosis, and bursting pressure; they were also examined histologically for collagen content estimation and blood vessel formation.

RESULTS

Mean operative time was 35 minutes (SD 5) for CSA and 35 minutes (SD 5) for HRA. There was 1 postoperative death in the HRA group. A postmortem examination revealed no evidence of anastomotic leak. The remaining 23 animals were assessed as planned. There was no evidence of anastomotic dehiscence in any animal. There was no significant difference in adhesion formation (P =.09), stenosis (P =.6), or bursting pressure (P =.2) between HRA and CSA groups. Collagen (P =.007) and blood vessel (P =.002) formation were significantly increased in HRA.

CONCLUSIONS

HRA treated with Focalseal heal well and have similar strength to CSA. This technique may prove valuable in procedures such as laparoscopic bowel resection.

Laser Soldering and Welding for Ossicular Reconstruction: An in Vitro Test

To evaluate the possibility of laser application in ossicular reconstruction, soldering and welding of bony tissue with proteineous materials was performed by using a Co2 laser, and the bonding strength of these materials was measured with a gradual weighing system. The soldered and welded surface of bone was observed with a scanning electron microscope. Additionally, welding of human ossicles and synthetic materials was experimentally tried with lasers, and morphologic changes were observed and recorded. A scanning electron microscopic examination was also done. A 40% albumin solution and commercial fibrin glue showed the best bonding strength. Bridging of denatured protein solder may be a mechanism of bonding. Polycel was melted by using a laser beam, and melted Polycel covered the surface of the ossicle. However, the bonding strength was not enough to use, and exact measurement of bonding strength was not possible. These results suggested the possibility of laser soldering and welding in ossicular reconstruction, especially with ossicle or cortical bone.

Estudo clínico comparativo entre anastomose colocólica com anel anastomótico biofragmentável e com sutura manual não absorvível

A anastomose com sutura é método consagrado, apresentando desvantagens teóricas representadas pelo trauma tecidual, edema e alteração da microcirculação. Além disso, o fio de sutura, sendo corpo estranho, determina reação inflamatória, propiciando a aderência e a proliferação de bactérias, assim como de células neoplásicas que seriam evitadas ao se usar método de anastomose sem sutura. A procura por método de anastomose em que não se utilizasse fio de sutura vem sendo realizada desde o início deste século. Com o advento das novas aquisições tecnológicas foi desenvolvido método de anastomose sem sutura através do anel biofragmentável. Esse anel sofre desintegração por hidrólise, sendo eliminado com a evacuação, não permanecendo corpo estranho na anastomose. Esse instrumento permite a realização de anastomose sem sutura, por meio da compressão das paredes intestinais justapostas. O objetivo desse estudo prospectivo e casualizado, foi o de comparar os resultados clínicos e endoscópicos de anastomoses colocólicas, eletivas e de baixo risco, realizadas com anel biofragmentável e com fio de sutura não absorvível. CASUÍSTICA E MÉTODOS: A casuística foi composta por 36 doentes, divididos em dois grupos de 18, que foram denominados Grupo I (anel biofragmentável ) e Grupo II (sutura com fio não absorvível ), constituídos de doentes comparáveis. RESULTADOS: Os parâmetros de avaliação do período intra-operatório, revelaram que a anastomose com anel biofragmentável despende menor tempo para sua realização. Não se detectou diferença estatisticamente significante entre os dois grupos com relação à incidência de complicações pós-operatórias, mortalidade e avaliação clínica ambulatorial. A incidência de deiscência anastomótica só ocorreu no Grupo I. A análise endoscópica da anastomose no período pós-operatório não demonstrou diferença quanto à perviedade, contratilidade, elasticidade e grau de epitelização. O Grupo II apresentou maior incidência de fio de sutura na anastomose em relação ao Grupo I sendo esta diferença estatística significante. CONCLUSÕES: O anel biofragmentável permite a realização de anastomose de colo mais rápida do que aquela realizada com fio de sutura. Este método de anastomose determinou, na análise global da complicações clínicas, resultados semelhantes ao uso de fio de sutura. O método de anastomose sem sutura apresentou o inconveniente de determinar maior incidência de deiscência anastomótica e como vantagem estabeleceu presença de corpo estranho na anastomose em menor porcentagem.

Intestinal anastomosis by use of the biofragmentable anastomotic ring: is it safe and efficacious in emergency operations as well?

PURPOSE

Although sutureless anastomosis by use of the biofragmentable anastomotic ring is now accepted as an alternative to conventional manual sutured or stapled methods in elective enterocolic surgery, its applicability to emergency enterocolic surgery has not yet been established. The aim of this prospective study was to determine whether the biofragmentable anastomotic ring anastomosis in emergency enterocolic surgery could be performed as safely as in elective surgery or as emergency handsewn anastomosis.

METHODS

To evaluate the safety and efficacy of sutureless bowel anastomosis by use of the biofragmentable anastomotic ring in emergency enterocolic surgery, a prospective, randomized study was undertaken to compare the biofragmentable anastomotic ring with conventional handsewn anastomotic technique. One hundred nineteen patients who required emergency laparotomy were randomly assigned to two groups: 56 patients (47 percent) underwent 58 biofragmentable anastomotic ring anastomoses, and 63 patients (53 percent) underwent 65 sutured anastomoses. In addition, the safety and efficacy of the biofragmentable anastomotic ring in emergency surgery were compared with those of the biofragmentable anastomotic ring in 86 elective biofragmentable anastomotic ring anastomoses performed in 84 patients during the same period of time.

RESULTS

Specific intraoperative complications related to use of biofragmentable anastomotic rings occurred in six patients (10.7 percent), and another new biofragmentable anastomotic ring anastomosis was constructed in one patient. These reflected learning-curve errors, but they did not adversely affect the outcome. No statistical differences were observed among the groups with respect to wound complications, postoperative bleeding, intra-abdominal abscess, intestinal obstruction, or postoperative death. As for anastomotic leakage, six patients, two in each group, had complications of anastomotic failure, wherein four colonic fistulas required a diversion and two enteric fistulas closed spontaneously. Although there were no statistically significant differences in incidence of leaks among groups (P = 0.4522), two fistulas in colocolic anastomoses, one in the suture group and the other in the biofragmentable anastomotic ring group, manifested the risk of primary anastomosis in emergency colon resection. Seven patients, three in the elective biofragmentable anastomotic ring group and two each in the emergency suture and biofragmentable anastomotic ring groups, died after the operation, but no deaths were directly attributed to the anastomotic technique used.

CONCLUSION

The data suggest that the biofragmentable anastomotic ring is a safe and reliable alternative to conventional handsewn anastomosis in emergency enterocolic surgery, where the rapidity and security of anastomosis may be critical. Consideration, however, should be given to emergency primary colocolic or colorectal anastomosis, because of a high risk of anastomotic failure, although there are too few cases for a definite conclusion.

Carbon dioxide laser tissue welding: an alternative technique for tubal anastomosis?

Microsurgical tubal anastomosis is the gold standard for treatment of tubal occlusion. The present study was performed to establish the feasibility of tubal anastomosis by welding tissue with a defocused CO2-laser beam during laparotomy and with an endoscope. In an animal experiment, 70 white New Zealand rabbits were randomized in 2 study groups (E1, E2) and 3 control groups (C1, C2, C3) as follows: C1, 10 animals, no operation, as controls for the efficiency of the insemination technique; C2, 5 animals, spontaneous healing after tubal segment resection, to quantify spontaneous recanalization of the tube; C3, 15 animals, microsurgical end-to-end adaption after tubal segment resection; E1, 20 animals, laser welded anastomosis after segment resection via laparotomy; E2, 20 animals, laparoscopic laser welded anastomosis after segment resection. The pregnancy rate in C1 was 80%. None of the animals in C2 but 60% of the rabbits in C3 conceived. After sutureless anastomosis by laser welding 50% of the laparotomized, and 40% of the laparoscopically operated group became pregnant. Morphological examination of the oviducts after relaparotomy showed comparable patency rates of 70% in C3, 70% in E1, and 65% in E2. Whereas no dehiscence of anastomoses was observed in C3, 20% of the welded tubes in E1 and 22.5% in E2 were dehiscent. Tubal anastomosis took approximately three times as long laparoscopically as during laparotomy. Thus, laser welding as a sutureless alternative technique of tubal anastomosis should be viewed critically. A reduction of sutures through laser-assisted anastomosis might, however, be considered.

Healing in the gastrointestinal tract

Healing in the GI tract is rapid when free of complications: Unlike cutaneous healing, in which progress can be observed on a daily basis and intervention instituted early if necessary, healing of the intestinal anastomosis is anatomically obscured from inspection, allowing the surgeon only the patient's parameters of general well-being to judge the success of the operation. For the same reason, complications usually require re-operation, with the associated morbidity of a laparotomy and additional general anesthetic. This places a great responsibility on the surgeon to be cognizant of all the preoperative, intraoperative, and postoperative factors relating to anastomotic healing that might compromise the healing process. Bearing these in mind, along with attention to technical detail, should limit complications to an acceptable level. Patients most at risk are (1) those who perioperatively develop physiologic problems that lead to shock, hypoxia, and resultant anastomotic ischemia, (2) those with radiation-induced tissue injury, (3) those with sepsis, and (4) those with preoperative bowel obstruction. Malnourishment, malignancy, diabetes, steroids, and age also influence outcome to varying degrees. Future advancement in the field of GI healing lies in our ability to manipulate the early struggle between collagen synthesis and collagen breakdown. A profound understanding of the molecular and biochemical pathways and the factors that control them will bring us closer to this goal. Clinically, this may be accomplished by the introduction of wound healing enhancers into the anastomotic site, possibly by incorporating them into suture materials, biofragmentable anastomotic rings, or staple materials. Already much is known about the influence of different cytokines and growth factors on collagen regulation, knowledge that will help resolve many of the long-standing problems associated with GI surgery.

Experimental oesophagogastric anastomosis: preliminary report of a new compression device that also fragments

Fifteen Beagle dogs underwent oesophagogastric anastomosis with a new device which enables a 'sutureless' compression anastomosis. The device fragmented and was passed in bits anally without causing obstruction. Immediate bursting pressure, tested in five dogs, was between 175 and 190 mmHg. The anastomoses of the remaining dogs were examined macroscopically and microscopically from day 6 to day 30. Healing was excellent with good muscular apposition and minimal residual inflammation.

Influence of soluble suture factors on in vitro macrophage function

Suture materials may interact with immune competent cells and thereby affect localized immunity. Macrophages are central to the inflammatory response and coordinate wound healing. They are also involved in the clearance of foreign material, bacteria and malignant cells. We studied the influence of soluble factors associated with silk, steel, nylon, polyglactin, polydioxanone and chromic catgut sutures on macrophage adherence, phagocytosis and the production of lysozyme and tumour necrosis factor. Soluble factors from suture materials influenced macrophage behaviour in vitro causing cellular activation, functional impairment and alterations in secreted levels of the cytokine tumour necrosis factor and the bactericidal agent lysozyme. Of the six materials studied, polyglactin had the most extreme effect, causing significant inhibition of cell adherence and lysozyme production. Silk also exerted a considerable effect on macrophages, significantly inhibiting adherence. In contrast, steel and polydioxanone media caused minimal inhibition of macrophage function although, as with all materials, they did activate the cells. This study has demonstrated that sutures release immunotoxic factors which considerably influence macrophage behaviour in vitro. These effects may have important clinical implications.

New device for biofragmentable anastomotic ring in low anterior resection

PURPOSE

The biofragmentable anastomotic ring (BAR) is now accepted as an alternative anastomotic method to handsewn and stapled anastomosis in colonic surgery. However, for a short rectal stump in a narrow pelvis, it is rather difficult to use the BAR in a low anterior resection.

METHOD

To overcome the difficulty, we designed and used a BAR-adapter to facilitate biofragmentable ring anastomosis following low anterior resection in eight patients with rectal cancers.

RESULTS

There was no case in our series having received conversion to other methods. There was no significant complication associated with this technique.

CONCLUSION

With the BAR-adapter, the applicability of the BAR can be greatly expanded in colorectal anastomosis following low anterior resection.

Protection of intestinal anastomoses by biodegradable intraluminal bypass tubes under the condition of general peritonitis: an experimental study on the CLP model in rats

The purpose of this experimental study was to affirm the protective effect of biodegradable tubes for the intraluminal bypass procedure under the adverse condition of general peritonitis. General peritonitis was induced by means of the cecal ligation and puncture (CLP) model in the rat. The leakage rate in the control group (n = 20) without anastomotic protection was 70 percent (14/20). In three therapeutic groups, each consisting of 20 animals, the intestinal anastomoses were protected by an intraluminal bypass tube of different biodegradable biomaterials (collagen-II, BCL-002, and BCL-004). The best results were noted in the collagen-II and BCL-002 groups, where the leakage rates could be reduced to 10 percent. These highly significant results (P = 0.0001) prove the feasibility of biodegradable biomaterials for the intraluminal bypass procedure in the rat, even in cases with underlying peritonitis.