The detailed study protocol was approved by the Research Ethical Committee of Assiut Faculty of Medicine and the trial was, afterwards, performed in the period from November 2009 till August 2010.
Seven mongrel dogs of both sexes weighing 16 to 22 kg were anaesthetized, after 8 hours fast, using intravenous pentobarbital (30 mg/kg). They were intubated with cuffed endotracheal tube and allowed to ventilate using 2% halothane inhalation vaporized with 100% oxygen. At the time of induction of anesthesia, intravenous amoxicillin (5 mg/kg) was given.
Midline abdominal incision was used to expose the gall bladder and the CBD which is transected immediately distal to the confluence of right hepatic duct with extension of the incision in the right hepatic duct to produce a wider stoma.
A piece from the middle 1/3 of the greater curvature of the stomach, 10-15 cm from pylorus and 5 × 3 cm in diameter, was completely separated from the stomach with its blood supply based upon right gastroepiploic vessels which were mobilized by meticulous dissection (Figure , , and ). The resulted defect in the stomach was closed in two layers. The piece of the stomach wall was fashioned as a tube over a silicon catheter of 4 mm diameter which later acted as an anastomotic stent (Figure and ). The distal part of the CBD was anastomosed to the newly fashioned tube which in turn anastomosed to the duodenum 2-3 cm distal to the pylorus (Figure , and ). Both anastomoses were mucosa to mucosa using 5/0 Vicryl (Ethicon inc., Johnson & Johnson company) interrupted sutures. The posterior row of sutures was placed followed by the anterior row. The stent was fixed by a stitch of the same suture type to the CBD wall to prevent slipping and its distal tip was placed in the duodenum.
Operative photo: Shows mobilization of the right. gastroepiploic vessels from the greater curvature of the stomach. a) Right gastroepiploic vessels.
Operative diagram: Illustrates figure 1. a) Right gastroepiploic vessels.
Figure 3 Operative photo: Showing a pedicled piece of the stomach wall based on the right gastroepiploic vessels. a) Right gastroepiploic vessels. b) Piece from the middle 1/3 of the greater curvature of the stomach. c). Closure of defect at the greater curvature (more ...)
Operative diagram: Illustrates figure 3. a) Right gastroepiploic vessels. b) Piece from the middle 1/3 of the greater curvature of the stomach.
Operative photo: Showing fashioning of gastric tube over a catheter. a) Right gastroepiploic vessels. d). Piece from the stomach wall fashioned as a tube. e) catheter.
Operative diagram: Illustrates figure 5. c) Closure of defect at the greater curvature of the stomach. d) Piece from the stomach wall fashioned as a tube. e) Catheter.
Figure 7 Operative photo: Showing the anastomosis between the distal end of CBD to the fashioned gastric tube. d) The pedicled gastric tube. f) Anastomosis of the gastric tube to the CBD at the site of confluence of the right hepatic duct. g) Right hepatic duct. (more ...)
Figure 8 Operative diagram: Illustrates anastomosing the newly fashioned gastric tube to both the distal end of CBD and the duodenum. d) The pedicled gastric tube. e) Silicon catheter. f) Anastomosis of the gastric tube to the CBD at the site of confluence of (more ...)
Figure 9 Postmortem specimen: Showing anastomosis of the newly fashioned gastric tube to both the distal end of CBD and the duodenum. d) The pedicled gastric tube. f) Anastomosis of the gastric tube to the CBD at the site of confluence of the right hepatic duct. (more ...)
After thorough haemostasis, the abdominal cavity was washed with saline and closed with intraperitoneal suction drain in position. Prior to extubation, intramuscular tramadol HCl 6 mg/kg was given and thereafter daily for three days for postoperative analgesia.
Postoperatively, all dogs were fed with standard dog chow and allowed free access to water and free movement in their cages. Intravenous amoxicillin 5 mg/kg were given every 8 hours for 10 days.
The animals were followed up for any biliary complications in the form of obstructive jaundice, cholangitis or biliary leakage.
Blood samples were obtained from the jugular vein of the canine both at the time of surgery and six weeks later at the time of euthanasia. Samples were allowed to clot for 30 minutes prior to centrifugation at 1500 × g for seven minutes and subsequently stored in plastic Eppendorf tubes at -20°C for no longer than one month until analysis. Liver functions tests were performed including serum total bilirubin, alkaline phosohatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). These tests were performed on "Hitachi 911 automatic analyzer" (Boehringer-Mannheim). The normal range for dogs are (0.1-0.6 mg/dL) for bilirubin, (10.6-101 U/L) for ALP, (8.2-57 U/L) for ALT and (8.9-49 U/L) for AST [7
Six weeks after the procedure, the abdomen was explored again under general anesthesia for any biliary leak, intraabdominal collection, disrupted anastomosis or anastomotic stricture. An operative specimen was obtained including the liver, extra hepatic biliary channels, gastric tube, duodenum and stomach before sacrifice of the animal (Figure ). Grossly, we measured the circumference of the anastomoses of the gastric tube with both CBD and duodenum (Figure and ). Thereafter, the specimens had been fixed in 10% formalin for 24 hours before they were trimmed. Sections were routinely processed. Five micron-thick sections were cut from paraffin blocks, and stained with hematoxylin and eosin stain for histological examination (Figure , , and ).
Figure 10 Postmortem specimen: Showing the interior of the pedicled gastric tube, the biliary tract and the duodenum. i) Tube into gall bladder lumen. j). Tube in the right hepatic duct. k) Tube in the left hepatic duct. l) Interior of the duodenum. m) Interior (more ...)
Postmortem diagram: Illustrates figure 10. i) Tube into gall bladder lumen. j). Tube in the right hepatic duct. k) Tube in the left hepatic duct. l) Interior of the duodenum. m) Interior of the pedicled gastric tube.
Microscopic examination: Showing the anastomotic line between the pedicled gastric tube and common hepatic duct, ×4.
Microscopic examination: Showing the common hepatic duct showing regeneration of the epithelium. The submucosa reveals the presence of proliferating fibroblasts with collagen deposition and infiltration with inflammatory cells, ×20.
Microscopic examination: Showing the anastomotic site between the pedicled gastric tube and duodenum, ×10.
Figure 15 Microscopic examination: Showing the submucosa at the junction between pedicled gastric tube and duodenum showing proliferating blood capillaries, proliferating fibroblasts with collagen deposition, and infiltration with inflammatory cells ×20. (more ...)
First clinical case: in December 2010, a 45 year female presented to the authors with external biliary leak two weeks after open cholecystectomy. The patient had a past history of exploration for rupture mesenteric cyst with resection anastomosis of part of the small intestine five years before. Abdominal ultrasonography showed moderate right sub hepatic biliary collection. Serum bilirubin, alkaline phosphatase and liver aminotransferases were elevated. Endoscopic retrograde cholangiopancreatography showed complete ligation of the distal end of the CBD. After obtaining an informed consent from the patient explaining all the possibilities of surgical procedures including the isolated pedicled gastric tube technique, she was explored through generous right subcostal incision with upward midline extension. Extensive adhesions was taken down to reach the proximal CBD about one cm from the confluence of the right and left hepatic ducts. The distal CBD end was dissected and the ligature removed with confirmation of the patency of the sphincter of Oddi. The gap between the proximal and distal CBD ends was about three cm. Construction of a Roux-en-Y jejunal limp seemed very difficult due extensive adhesions from the past operative procedure for intestinal resection. The high position of the proximal CBD end made hepaticoduodenostomy inappropriate. End to end choledochocholedochostomy was not an option due to the high rate of future stricture and the long gap between the two CBD ends. Consequently, the surgeons preferred to use the new technique of isolated pedicled gastric tube interposition. Because the distal CBD was intact, we decided to interpose the gastric tube between both ends of the CBD to keep the sphincter of Oddi physiologically intact. A four mm stent was left in position from the proximal end of the CBD through the gastric tube to the duodenum and fixed to the CBD wall with fine 5/0 Vicryl suture. The patient was followed up clinically and by liver function tests and endoscopic retrograde cholangiopancreatography (ERCP). Written informed consent was obtained from the patient for publication of her data and any accompanying images.