Postoperative tolerance to glucose and sugar substitutes.

In 51 surgical intensive-care patients, who were given 400 to 650 g glucose per day i.v., 18% of arterial blood sugar values were found to be above 250 mg/100 m1 in spite of frequent insulin administration. In 8 lobectomized patients increased plasma levels of pancreatic glucagon, cortisol, and growth hormone were observed which may in part explain postoperative glucose intolerance. In addition previous carbohydrate deprivation was found to impair glucose tolerance. Several measures are suggested to reduce the incidence of hyperglycemia during i.v. glucose feeding. In a further study 24 cholecystectomized or vagotomized patients received in alternate sequence either a combination of glucose (G), fructose (F) and xylitol (X), the G/F/X-ratio being 1/2/1, or glucose alone for 5 days. The infusion rate was 1.42 g carbohydrate/kg/24 hrs. On operation day and was increased by the same amount every day up to 7.14 g/kg/24 hrs. Tolerance was good in both groups but urinary losses of infused substrates were higher in the group receiving the GFX-combination. It is concluded that after surgery of intermediate magnitude the GFX-combination offers no advantage over glucose alone. However, in severely ill patients, where glucose intolerance is more pronounced, further carefully monitored studies with sugar substitutes appear of interest.