Intraoperative bowel irrigation improves anastomotic collagen metabolism in the left-sided colonic obstruction but not covering colostomy

This study investigated the effects of intraoperative colonic irrigation and proximal diverting end colostomy after segmental bowel resection in experimental left-colonic obstruction on anastomotic healing. Simple obstruction of descending colon was performed in male Sprague-Dawley rats. After 24 h we performed segmental colonic resection and anastomosis in the control group (n = 15); resection, anastomosis, and covering colostomy in the colostomy group (n = 14); resection and anastomosis after antegrade colonic lavage through cecum by using isotonic saline solution in the irrigation group (n = 13). In rats that were killed 7 days later anastomotic dehiscence and bursting pressure and tissue hydroxyproline concentration at the anastomosis were measured. No significant differences were observed between groups in terms of anastomotic dehiscence, bursting site, or pressure. The hydroxyproline concentration was significantly higher in the irrigation group than the control group (P = 0.025) and the colostomy group (P = 0.029), but no difference was noted between the control group and the colostomy group. These findings suggest that intraoperative antegrade colonic irrigation in the acute left-sided colonic obstruction positively affects collagen metabolism at the anastomotic site; if the anastomosis is performed without bowel cleansing, covering colostomy does not improve collagen metabolism.     

The effect of recombinant growth hormone on the strength of ileal anastomoses in a rat model

OBJECTIVE: In gynecologic surgery, the ileum is the primary site of bowel injury. Recombinant growth hormone (rGH) has been shown to improve the strength of colonic anastomoses in experimental models. The purpose of this study is to evaluate the effect of rGH on small bowel anastomoses, specifically in the ileum. METHODS: Twenty large female rats underwent segmental ileal resections and end-to-end ileoileostomies. The rats were randomized to be treated for 7 postoperative days with either rGH (2.0 mg/kg/day) or placebo starting on the day of surgery. On the seventh postoperative day, a segment of ileum surrounding the anastomosis was resected. The anastomoses were tested for breaking strength on a tensiometer and for tissue concentrations of hydroxyproline. RESULTS: The ileal anastomotic breaking strength in the rGH group was 163.5 +/- 6.0 g (mean +/- standard error). In the placebo group, the breaking strength of ileal anastomoses was 125.0 +/- 3.0 g (P < .001). No significant difference was demonstrated with respect to the hydroxyproline concentration between the rGH group (15.2 +/- 2.0 micrograms/mg) and the placebo group (14.6 +/- 1.0 micrograms/mg). CONCLUSION: In an animal model, a 31% increase in ileal anastomotic breaking strength was induced by rGH administration. With further research this may translate into decreases in the surgical complications that occur in ileal anastomoses. Furthermore, these serve as preliminary data to a study that evaluates the effect of rGH on ileal anastomoses in radiation-injured bowel.     

Circular intestinal and esophageal suture with universal suture device (experimental trial)

A universal suture device (USD) able to make simultaneous two-line and cross-shaped circular clips stitches on various tube-shaped organs (vessels, intestines, esophagus, stomach, ets), creating end-to-end and end-to-side anastomosis with the external cuff is proposed. The results of experimental trials of USD and its clinical use in anastomosing main vessels were published before (8, 9, 11, 12). In this article the results of experiments with the use of USD in intestinal and esophageal sutures in 35 dogs are analysed. There were 4 series of experiments with 45 anastomoses (31 intestinal and 14 esophageal anastomoses). The anastomosed segments of the intestines and esophagus healed at the level of the lower side of the cuff. The cuff completely resumes its shape in 2.5-5 months, and the clips come off by month 7-8 after the surgery. The mucous layer of the esophagus straightened by the 2-3d month, while adventitial-muscular layer does not straigheten at all, and the clips from it could be found till the 10th month after the surgery. There were no cases of anastomotic incompetence.     

Effects of early postoperative 5-fluorouracil and ageing on the healing capacity of experimental intestinal anastomoses

BACKGROUND: Results from a previous study suggested that advanced age does not affect early repair of experimental intestinal anastomoses. The present study aimed to establish whether anastomotic healing is impaired more easily in old animals by immediate postoperative chemotherapy. METHODS: Young adult (2-3 months) and old (27-30 months) rats underwent resection and anastomosis of both ileum and colon. Within each age group, subgroups received intraperitoneal saline or 5-fluorouracil in a dose of 15 or 20 mg per kg per day from the day of operation onwards. After 7 days, anastomotic healing was assessed by wound strength and collagen deposition in the wound area. RESULTS: No differences were found between young and old control groups. The higher dose of fluorouracil induced severe loss of strength with concomitant reduction of wound collagen, which was similar in both age groups (ileum: from 52(13) to 24(8) volume per cent in young animals and from 56(10) to 20(9) volume per cent in old animals; colon: from 58(10) to 37(18) volume per cent in young animals and from 65(5) to 30(17) volume per cent in old animals). The lower dose of fluorouracil induced a significantly greater loss of strength, measured as the bursting pressure, in the old animals (150(49) versus 201(59) mmHg in colon of young rats). CONCLUSION: In this model early anastomotic repair in older animals proceeds normally under optimal conditions, but it is more easily disturbed in the presence of fluorouracil.     

Intra-operative irradiation prolongs the presence of matrix metalloproteinase activity in large bowel anastomoses of the rat

There exists a growing interest in intra-operative radiation therapy as a treatment modality for large bowel cancer. In a previous experimental study we showed that high-dose intra-operative irradiation delays the healing of colonic anastomoses. However, the contribution of proteases is unknown. In the present study, the gelatinolytic and collagenolytic activity in the healing anastomoses is investigated. After a resection of a 1-cm length of colon (uninjured colon), the rats were irradiated with a single dose of 25 Gy, either to the proximal limb, referred to as the proximal group, or to both proximal and distal limbs of the bowel, referred to as the combined group, before anastomotic construction. Both groups were compared to a control group with anastomoses which were sham-irradiated. The animals were killed 1, 3 or 7 days after operation. The gelatinolytic activity in uninjured and anastomotic tissue was quantified by gelatin zymography and the collagenolytic activity by an assay using a fibrillar rat collagen substrate. Compared with resected uninjured colon, most of the gelatinolytic activities were markedly increased in anastomotic tissue of all groups during the first postoperative week, and new additional activities were detected. The additional metalloproteinases (the 95-kDa family) of both irradiated groups were significantly elevated compared to the anastomoses of the sham-irradiated control group at 7 days after operation. In anastomotic tissue of all groups, the collagenolytic activity of the tissue was also significantly increased at 1 and 3 days after construction with respect to the resected, uninjured colon. After 7 days this effect had disappeared for the sham-irradiated anastomoses, but the activity in the anastomoses in both the proximal and combined groups remained significantly elevated. The findings provide evidence that intra-operative irradiation prolongs the presence of elevated gelatinolytic and collagenolytic activities in colon anastomoses. It may contribute to a reduced or delayed accumulation of collagen and other matrix proteins that supply anastomotic strength.     

Postoperative motor function and mucosal blood flow of lower esophagus: comparison between terminal esophagoproximal gastrectomy and esophageal transection for esophageal varices

Reflux esophagitis and anastomotic ulcer are potential complications associated with surgery for esophagogastric lesions. This study compared 10 cases following terminal esophagoproximal gastrectomy (TEPG) for esophageal varices and 20 cases following esophageal transection (ET) for esophageal varices with respect to postoperative motor function and mucosal blood supply, to ascertain the reason for the development of anastomotic ulcer. Endoscopic findings showed that anastomotic ulcers were detected more often after TEPG than after TR. Maximum swallowing pressure, high pressure zone pressure, and length did not differ between the two groups. However, maximum swallowing pressure in the lower esophagus after both procedures was significantly lower than in the control group (20 cases; p < 0.01). The results, measured by reflectance spectrophotometry, showed that the index of esophageal mucosal blood volume following TEPG is significantly lower than that following ET and in non-operated esophageal varices (10 cases; p < 0.01). Yet the index of oxygen saturation of hemoglobin was similar in the three groups. This study has demonstrated that patients undergoing TEPG have mucosal ischemia of the lower esophagus, causing the development of anastomotic ulcers.     

A new technique of esophagogastrostomy above the aortic arch--covering and suspending of the anastomotic area with mediastinal pleura flap

The postoperative anastomotic leakage is the most severe complication and the principal cause of death after resection of esophageal carcinoma. Especially, anastomosis above the aortic arch is accompanied by high incidence of anastomotic leakage usually with fatal prognosis. The authors improved the conventional method of anastomosis by using a mediastinal pleura flap to cover and suspend the anastomotic area with excellent result. From January of 1990 to April of 1995, 210 patients with esophageal carcinoma were so treated. No anastomotic leakage or stricture developed. Only one patient died of extensive myocardial infarction with an overall mortality of 0.47%. The major merit of this procedure was that the mediastinal pleura flap could cover the area of anastomosis and sustain the dragging force acting on this area, providing a better condition for the anastomosis to heal and thus reducing the possibility of anastomotic leakage.     

Successful in vivo and ex vivo transfection of pulmonary artery segments in lung isografts

OBJECTIVE: Gene transfer to lung grafts may be useful in ameliorating ischemia-reperfusion injury and rejection. Efficient gene transfection to the whole organ may prove problematic. Proximal pulmonary artery endothelial transfection might provide beneficial downstream effects on the whole graft. The aim of this study was to determine the feasibility of transfecting proximal pulmonary artery segments in lung isografts. METHODS: Male Fischer rats were divided into six groups. In vivo transfection: In group I (n = 7), a proximal segment of the left pulmonary artery was isolated and injected with saline solution by means of a catheter inserted through the right ventricle. After an exposure period of 20 minutes, clamps were removed and blood flow was restored. In group II (n = 7), the isolated arterial segments were injected with adenovirus carrying the Escherichia coli LacZ gene encoding for beta-galactosidase. Ex vivo transfection: In group III (n = 5), arterial segments were injected ex vivo with saline solution and in group IV (n = 5) with the adenovirus construct. In group V (n = 6), arteries were injected with saline solution and in group VI (n = 11) with liposome chloramphenicol acetyl transferase cDNA. In groups I to IV, animals were killed on postoperative day 3 and transgene expression was assessed by Bluo-Gal staining. In groups V and VI, animals were killed on postoperative day 2 and transgene expression was assessed by chloramphenicol acetyl transferase activity assay. RESULTS: Transgene expression was detected grossly and microscopically in endothelial and smooth muscle cells of pulmonary artery segments from all surviving animals of groups II and IV. In group VI, chloramphenicol acetyl transferase activity was significant in all assessed arterial segments. CONCLUSION: Significant transgene expression is observed in proximal pulmonary artery segments after both in vivo and ex vivo exposure.     

Abnormalities of neuropeptides and neural markers in the esophagus of fetal rats with adriamycin-induced esophageal atresia

BACKGROUND/PURPOSE: To investigate the distribution of neural markers and neuropeptides in esophageal atresia (EA). METHODS: A fetal rat model with Adriamycin-induced EA was used. The animals were divided into four groups: (1) control group, (2) saline-injected group, (3) Adriamycin administered but without the development of EA, and (4) Adriamycin-induced EA group. Specimens of the distal esophagus from each group were immunostained using antibodies to S100, protein gene product 9.5 (PGP), somatostatin, vasoactive intestine peptide (VIP), bombesin, galanin, substance P, neuropeptide Y (NPY), calcitonin gene-related product (CGRP), met-encephalin, nitric oxide synthase, and tyrosine hydroxylase. RESULTS: The total cross-sectional area of the distal atretic esophagus was significantly smaller than controls (P = .01), the submucosa being the component most affected (0.0465 v 0.0234 mm). Immunoreactivity for S100 and galanin were significantly elevated in the atresia group (0.0288 v 0.0079 and .001 v 0.000). In addition, there was also an increase in CGRP and Substance P in the atretic group. CONCLUSION: The elevated levels of S100 and galanin could explain the disordered motility observed in patients who had esophageal atresia.     

The laboratory study on biofragmentable anastomosis rings (BAR) in gastrointestinal tract reconstruction

To study and investigate the feasibility of biofragmentable anastomosis ring (BAR) for gastrointestinal (GI) tract reconstruction, we performed gastroenterostomy in 34 dogs. BAR anastomoses were performed with proper outer diameter and gape size in small bowel in 8 cases, in large bowel in 11 cases, in esophagus in 12 cases, in esophago-intestinal in 2 cases, in gastrojejunum in 1 cases. The postoperative serial X-ray examinations showed that BAR maintained good integration two weeks postoperation. The ring disintegrated into several small fragments that passed out of the body in feces from the 14th postoperative day after surgery. All of the dogs were killed on the 28th operative day and autopsied. The anastomosis site had smooth serosa and scar membrane in gross and were substituted by regenerative fibrous tissue. The specimen barim-air double contrast X-ray revealed that GI tract was coherent without leakage and stenosis. Therefor, the authors recognized that BAR can be recommended as a safe technique in GI operation.     

Esophageal reconstruction with free jejunal grafts: an experimental study

Replacement of a long segment of esophagus for esophageal atresia or severe stenosis remains a special problem in children. The following studies were designed to test the hypothesis that a section of small bowel without serosa could survive as a free autologous transplant to replace part of the mediastinal esophagus. Laparotomy was performed in 20 adult cats, a loop of small bowel was resected and an end-to-end jejunojejunostomy was completed. The serosa of the resected bowel was removed and the mucosa-muscularis graft was used to replace a segment of the middle esophagus that was resected via a right thoracotomy. The interposed graft was entirely wrapped with adjacent skeletal muscle flaps. Postoperative studies include barium swallow and cine esophagograms, histology and blood vessel casts. Results are presented which show anatomical and functional survival of 16 grafts without blood vessel anastomoses or intrinsic vascular pedicles.     

The value of early postoperative oesophagography following repair of oesophageal atresia

The aim of the study was to examine the relationship between anastomotic leaks and the development of symptomatic anastomotic strictures after primary repair of oesophageal atresia (OA) with or without tracheo-oesophageal fistula (TOF) and the prognostic value of the anastomotic appearance on postoperative oesophagography. The records and X-ray films of 49 patients with OA with or without TOF admitted between January 1990 and June 1995 were reviewed retrospectively. Of these, 37 had a primary repair (34 immediate and 3 delayed) and a postoperative contrast swallow was done between day 5 and day 30 (median day 7). Radiological leaks were documented. In addition, the maximum transverse diameters of the upper pouch and anastomotic region and the length of the anastomotic narrow segment were measured; the ratio of upper-pouch diameter to that of the anastomosis was calculated (anastomotic index, AI). The need for dilatation of symptomatic anastomotic strictures and for repeat dilatation as a separate episode were documented. Of the 37 patients, 4 developed an anastomotic leak (11%), 3 radiological and 1 clinical. A symptomatic stricture occurred in 55% of patients. There was no correlation between a leak and later development of a symptomatic stricture, although the small number of patients with leaks precluded definite conclusions. No radiological leak progressed to a clinical leak. There was no correlation between the AI or the length of the anastomotic narrow segment and the need for dilatation, the need for repeat dilatation, or the number of dilatations. In this study, the presence of a leak, the AI, and the length of the narrow segment on early postoperative contrast swallow did not correlate with the later development of a symptomatic stricture. A radiological leak was of no clinical significance. Since major leaks are apparent clinically, an early routine contrast study did not influence management and is not necessary.     

The role of a bidirectional cavopulmonary anastomosis in the correction and palliation of complex congenital cardiopathies

Between May 1990 and January 1998, 68 patients underwent bidirectional cavo-pulmonary anastomosis. We evaluated all patients in whom the bidirectional cavo-pulmonary anastomosis was associated with additional pulmonary flow (group A) and those in whom it was associated with biventricular repair (group B). Group A included 23 patients (33.8%), 14 males and 9 females, mean age 25 years and 6 months (range 4 months-16 years). Diagnoses were double outlet right ventricle (6), univentricular heart (6), tricuspid atresia (5), congenitally-corrected transposition of the great arteries with ventricular septal defect and pulmonary stenosis (3), right isomerism (2) and pulmonary atresia with atrioventricular canal (1). Group B included 13 patients (19.1%), 6 males and 7 females, mean age 13 years and 7 months (range 1 year-37 years). Diagnoses were pulmonary atresia with intact ventricular septum (4), Ebstein's anomaly (3), tetralogy of Fallot (3), atrioventricular canal (1), hypoplastic right ventricle (1), and pulmonary and tricuspid insufficiency (1). Four patients (17.3%) in group A died in the postoperative period, whereas there was no postoperative mortality in group B. Follow-up data were available in 31 patients (19 from group A, 13 from group B). Mean follow-up was 1 year and 6 months (range 30 days to 6 years). Evaluation was done by NYHA class functional status. In group A, 14 patients are doing well (NYHA I or II), while five patients (26.3%) underwent Fontan operation with one death. All group B patients are currently doing well (NYHA class I or II). In group A, complications were pericardial effusion (7), transient superior vena cava syndrome (5), pleural effusion (4), chylothorax (1) and rhythm disturbance (1). Complications in group B involved neurological events (2), pleural effusion (1) and rhythm disturbance (1). Bidirectional cavo-pulmonary anastomosis can be associated with additional pulmonary flow with good short- and intermediate-term outcome. Concern remains for the ability to properly regulate the amount of effective pulmonary blood flow. Bidirectional cavo-pulmonary anastomosis can be associated with biventricular repair in patients with diminutive right ventricles, amenable to anatomic complete correction, with good clinical outcome.     

Upper esophageal stenosis: two case reports

Esophageal stenosis caused by an intrinsic congenital deformity is uncommon in infants and children. The main forms of stenosis are congenital esophageal web congenital stricture caused by tracheobronchial remnants, and congenital idiopathic muscular hypertrophy. The authors report on two patients who were successfully treated and managed after being diagnosed as having upper esophageal stenosis. One patient underwent resection of the web and primary anastomosis of the esophagus and was discharged 6 days after surgery. After 1 year, this patient has had no symptoms of dysphagia or other postoperative difficulties. The second patient underwent balloon dilatation of the esophageal stricture and was discharged on the day of surgery; however, this patient required numerous repeat dilatations.     

Esophagogastrostomy with the EEA stapler

Esophagogastric anastomosis was performed with the EEA stapler in 31 patients who underwent esophageal resections. Anastomoses were accomplished at all levels of the thoracic and cervical esophagus by a variety of approaches. Routine barium cine-esophagograms obtained at seven days after operation failed to demonstrate an anastomotic leak in any patient. The operative mortality rate was 3% (1 of 31 patients). Technical problems occurred during the operation in three patients; in two of these an incomplete anastomosis may have resulted from the surgeon's error. All patients were able to swallow normally at the time of discharge. Late anastomotic stricture occurred in five patients, and responded to dilatation in all but one patient who had local tumor recurrence. We conclude that the EEA stapler allows rapid and reliable esophagogastric anastomosis. Successful use of the instrument requires strict attention to technical detail and awareness of possible pitfalls.     

PET evidence for an amodal verbal working memory system

To assess the influence of digestive juice on the pancreatic stump when pancreaticogastrostomy was performed after pancreatoduodenectomy, the pancreatic stump was anastomosed to the intact stomach (group I), the stomach after partial gastrectomy (group II), or the jejunum (group III) in rabbits, and the nature of the digestive juice at the anastomotic site as well as the histologic changes of the pancreatic tissue were investigated. The digestive juice was highly acidic in group I, slightly acidic in group II, and almost neutral in group III. Histological examination of the pancreatic stump revealed extensive coagulative necrosis and delayed replacement with granulation tissue in group I, while there was less prominent liquefactive necrosis and early replacement with granulation tissue in groups II and III. Intraperitoneal abscess formation around the anastomotic site and atrophic fibrosis of the pancreas (similar to the changes after pancreatic duct ligation) occurred in 27.8% and 46.2% of group I rabbits, respectively, but no such changes were detected in groups II and III (both P < 0.05). These results indicate that the highly acidic gastric juice had a widespread corrosive effect on the anastomosed pancreatic tissue, and that partial gastrectomy may be necessary to prevent anastomotic leakage and pancreatic duct obstruction after pancreaticogastrostomy.     

Wound healing of intestinal anastomosis after digestive surgery under septic conditions: participation of local interleukin-6 expression

This study aimed to evaluate the integrity of anastomotic wound healing after digestive surgery under septic conditions and to observe local interleukin-6 (IL-6) expression around the anastomotic segment. Experimental animals were separated into lipopolysaccharide (LPS) and control groups. Each was injected with LPS or normal saline solution into the peritoneal cavity 24 hours before transection and anastomosis of the colon. The anastomotic bursting pressure (ABP) and tissue hydroxyproline concentration (HP) were measured as indicators of wound healing. Immunohistochemical staining for IL-6 was performed on tissue samples obtained from the anastomotic segment, lung, liver, and kidney. The reactive cells were counted by light microscopy. The ABP and HP were significantly lower in the LPS group than the control group 7 days after the surgery. In the LPS group, IL-6 expression around the anastomotic segment was enhanced 1 and 6 hours after surgery but suppressed 24 hours afterward. In contrast, IL-6 expression in lung, liver, and kidney was enhanced in the LPS group 24 hours after surgery but not in the control group. It is suggested that anastomotic wound healing is impaired after digestive tract surgery under septic conditions, and local IL-6 expression participates in wound healing.     

Restoration of the electrical activity and nervous apparatus following section of the stomach wall in dogs

In dogs, transection of the gastric wall at the level of incisura angularis, followed by end--to--end anastomosis, was made. The electrodes were implanted into the muscle wall of the two stomach segments. Electrical activity of the stomach wall on the 1st postoperative day showed dissociation in the spike activity between the two segments. 10 days later, first signs of sequence in the spike activity of the stomach above and below the anastomosis appeared. Microscopic examination revealed that regenerating nerve fibers formed a bridge over the scar. On the 16th day, groups of spike potentials from the gastric wall above the section propagated also in the stomach region below the anastomosis. Since the 14th day, the microscopic examination revealed newly formed synaptic endings on the ganglionic cells distal to the scar. After the 20th day, all signs of dissociation began to disappear.     

Primary reconstruction of esophageal atresia with distal tracheoesophageal fistula in a 740-g infant

A premature 740-g infant who had esophageal atresia and tracheoesophageal fistula was treated with a primary anastomosis. The postoperative recovery was excellent, but the need for close cooperation with neonatal intensivists is essential for survival.