Oddi Sphincter Function After Canine Pancreas Auto-transplantation With Bladder Drainage

Background and objectiveThe major roles of the Oddi sphincter (SO) are to regulate the flow of bile and pancreatic juice into the duodenum and to prevent the reflux of duodenal contents into the biliary and pancreatic duct. The motility of SO was composed of tonic contraction and phasic contraction. Neural factors and hormones and some drugs play important roles in the control of SO motility. The motility of SO was related to migrating motor complex(MMC) of the duodenum. Graft pancreatitis is one of the reasons of graft dysfunction with bladder drainage. The reflux of urine and pancreatic juice can cause graft pancreatitis. After transplantation, the graft was denervated and graft duodenum lost its normal MMC. Little was known about the function of SO and its effect on the graft function after pancreas transplantation with bladder drainage. The objective of this paper was to study the canine SO function after pancreas auto - transplantation with bladder drainage and the effect on the graft. Then drugs that relaxes SO were used to decrease motali-ty caused by SO disorder.MethodsHealthy adult mongrel dogs , either sexes,weighing 13 - 18kg were used. A triple lumen catheter connected via pressure transducer to a computerized recording system with a guide wire channel at its tip was used for SO manometry. The triple lumen catheter,measuring 1.7mm in diameter,with three -holes at 2 -mm intervals,perfused with sterile water at a rate of 0.25ml/min per channel by means of a low - compliance pneumohydraulic pump,connected via transducers to a computerized recording system.Normal canine SO manometry: The dogs were anesthetized with 30mg/kg ofintravenous pentobarbital sodium, and maintained under adequate anesthesia with 15 nag/kg of pentobarbital sodium as required. System blood pressure was monitored through a catheter placed into the femoral artery,The femoral vein was can-nulated and used for systemic administration of solutions and drugs. After an upper medium laparotomy by using aseptic technique, the biliary tree was identified. A small longitudinal incision was made in the common bile duct. A triple lumen catheter was cannulated and tied in the bile duct to avoid any leaks and occlusion of the orifice of the catheters. The catheter was sent into the duodenum. Intraduodenal pressure was taken as zero reference. Via 1 - mm station pull through technique,the catheter was placed just at the site of SO for 10 minutes. A basal recording lasting at least 5 minutes was obtained at the level of SO high pressure zone.Pancreas graft SO and SO in vitro manometry: The dogs were fast and anesthetized the same with the dogs in the control group. After a midline celiotomy with aseptic techniques, the tail of the pancreas was mobilized by division of the veins which drain the distal pancreas into the spleen vein. Then the head of the pancreas was mobilized without cutting the pancreaticoduodenal vessels. After li-gating and dividing the common bile duct at its entry into the duodenum, the lessen omentum was opened. The gastroduodenal artery and vein were dissect out at least 1cm from the bifurcation. The proximal duodenum was cut out 1cm distal to pylorus and closed. The distal duodenum was divided at the end of second part of duodenum. Thus the donor was skeletonized with intact vascular connections. Finally, the gastroduodenal artery and vein was removed and each graft was immediately flushed with cold ringer solution. Reestablishment of vascular connections to the autograft was accomplished by an end - to side anastomosis of the gastroduodenal vein to the right common iliac artery and end - to end anastomosis of the accompanying artery to the internal iliac artery. After reperfusion, the distal pancreas was resected. Gastrointestinal continuity was restored by the Roux -en - Y technique with cholecystojejunal,gastrojejunal and graft - duodenal -host bladder anastomosis. Average graft ischemia time was 30 - 40min. The bile duct residual of graft was placed under the skin. Fluid and antibiotics were given...