Perioperative and Surgical Complications Besides general monitoring, in the immediate postoperative period, specific care should be directed toward monitoring cardiovascular function. Insulin infusions are generally given for a few days to ensure rest of the islets. Because many patients have some form of diabetic gastropathy, a nasogastric tube is required for four to seven days. A urinary catheter is required for an extended period because of the large area of anastomosis to the bladder and the potential for neurogenic bladder. With rare exception, salvage of the graft is impossible and delaying a graft pancreatectomy can risk the recipient' s life.
Rejection is the leading cause of graft loss after pancreas transplantation.
Urinary amylase determinations remain the most useful biochemical parameter for detecting rejection in bladder-drained pancreas allografts. Rejection should be suspected when urinary amylase levels drop 25 percent an hour from stable posttransplantation baseline values on two consecutive measurements obtained at least 12 hours apart. Rejection can be confirmed histologically because tissue samples of the bladder-drained graft can be easily obtained by the cystoscopic transduodenal biopsy technique. After rejection, dehydration and metabolic acidosis are the most common adverse events seen after pancreas transplantation. There is obligatory loss of pancreatic secretions rich in sodium and bicarbonate into the urinary tract.