[Changes in serum electrolyte concentration and in urinary electrolyte excretion during the infusion of glucose or...

In groups of volunteers the concentration differences of phosphate potassium and sodium in serum were measured during 48-hour continuous infusion of glucose or glucose substitutes (fructose, sorbitol or xylitol). The dosage was 0.25 g/kg BW/hour. Additionally, the effect of fructose infusion in a dosage of 0.5 g/kg BW/hour was observed. Besides, the urinary excretion of sodium and of potassium was analysed. In contrast to short-term and high-dosed infusions of glucose or glucose substitutes, the phosphate concentration in serum was scarcely influenced. Only during high-dosed fructose infusion and during infusion of xylitol and sorbitol a small decrease in serum phosphate concentration was noticed. The effect of xylitol is pronounced. Additionally, the sodium concentration in serum was especially decreased during xylitol infusion. With regard to the sodium excretion - and less pronounced with regard to the potassium excretion - a gradual adaptation to the infusion of the electrolyte-free solution is observed. The excretion of the cations is more and more decreased. In particular the excretion of sodium and of potassium is very high in the initial period, i.e. in the course of the first twelve hours of the xylitol infusions. On the other hand, the potassium excretion is very low in the final period of the infusion of xylitol (during 36 hours up to 48 hours) in comparison to the other sugars.