Glucose, fructose, and xylitol in postoperative hypocaloric parenteral nutrition

The aim of the study was to use glucose, fructose and xylitol as alternative carbohydrates in hypocaloric parenteral nutrition (HPN) and to investigate their different nutritional effects. Twenty-four patients who had undergone elective gastrointestinal resection were examined in a prospective randomized study. Only metabolically normal patients between 30 and 65 years of age were admitted to the study. No patient with a body weight more than 20% above or below the normal weight of the patients was admitted. The study period extended from the operation day to the fifth postoperative day. The patients were given approximately 1.1 g amino acids and approximately 2.9 g carbohydrates per kg/B.W. and day using either glucose, fructose or xylitol as carbohydrates. The mean plasma glucose concentrations ranged between 6 and 8 mmol/l without insulin being supplied. There were no significant differences between the groups. However, the administration of glucose led to a somewhat larger dispersion range of the values. The labile plasma proteins (transferrin, prealbumin, retinol-binding protein) in the 3 groups revealed almost identical concentration courses. With N-losses between 51 and 57 g/4 days, only slightly negative cumulative N-balances were calculated (-4 to -13 g/4 days). No significant differences were observed between the 3 groups in the level of the urea-N production rates. Advantages which favor a general administration of fructose/sorbitol or xylitol in HPN could not be found in our investigation.