[Hemorheologic, micro- and macrocirculatory effects of an infusion of 500 ml of 6% medium molecular weight hydroxyethyl starch (Haes 200,000/0.5)].

In an open study the influence of hypervolemic hemodilution (Infusion of 500 cc hydroxyethyl starch 200,000/0.5 6% within 1 h) on macro- and microcirculation, fluidity of blood and conjunctival oxygen tension was investigated. Blood pressure and heart rate remained unchanged during and after the infusion. One hour after the infusion there was a tendency towards an increase in blood flow in the common carotid artery which then returned to normal again. The capillary circulation as well as the conjunctival oxygen partial pressure were significantly increased after 3 h. This correlated well with the decrease in plasma viscosity and erythrocyte aggregation. The effect of hemodilution using 6% middle molecular weight hydroxyethyl starch with a substitution degree of 50% on microcirculation was probably due to the rheological and not to the hemodynamic effect.