[Metabolism of sorbitol and xylitol in newborn and premature infants and the effect on blood sugar and lactates].

The glucose blood level shows a clear increase in neonates and premature infants with continuous intravenous infusion of sorbitol and xylitol at graded intake rates ranging from 0.5 g - kg(-1) - h(-1) to 1.0 g - kg(-1) - h(-1) when they are administered over a period of 2 to 3 hours. With an intake of 0.5 g - kg(-1) - h(-1) for both polyols a steady state is established after 60 and 90 minutes, respectively. With intake rates of 0.75 g - kg(-1) - h(-1) the xylitol blood level shows a continous increase until the end of infusion, whereas after a 3-hour infusion of sorbitol a steady state is finally established, but with clearly elevated blood levels. The values of the total clearnace of the polyols show a decrease with increasing intake rates and thus indicate a more difficult turnover. Therefore, a, a maximal intake rate of 0.25 g - kg(-1) h-1 should not be surpassed for long-term intravenous nutrition of neonates. The lactate concentration shows a distinct increase with an intake of 1.0 g - kg(-1) - h(-1) sorbitol. A significant increase of blood glucose is also observed after rapid infusion of 0.5 g - kg(-1) and 1.0 g - kg(-1) xylitol, whereas similar doses of sorbitol lead to a considerable delay of the increase of glucose. After rapid infusion of 1.0 g - kg(-1), both polyols lead to a significant increase of the blood lactate concentration. Therefore and because of the delayed increase in blood glucose after sorbitol, the rapid infusion of the polyols must be avoided. From our findings of the metabolic rates of the polyols it can be suggested that the polyols in part can be used instead of glucose in parenteral nutrition also in the neonatal period. Further studies are necessary to prove if the polyols have clear-cut advantages over glucose in neonates.