[Preoperative autologous blood donation, effect of hydroxyethyl starch on the reticuloendothelial system and opsonins].

The effect of 6% low molecular weight (LMW) HES (MW 270,000) on reticuloendothelial function was studied in 9 male patients, median of age 50 years, who were scheduled for vascular surgery. An erythrocyte clearance test (Anti Rh) labeled with 99 mTc, evaluating primarily the splenic section of the RES, showed a considerable variation (37-87%) prior to hemodilution. 24 hours after replacement of 15 ml/kg body weight of blood, there was no significant change of the clearance rate, a follow up weeks later approached the base line values. Plasma opsonins like fibronectin, complement fraction 3, complement fraction 4 and immunoglobulin G showed a proportional decrease following hemodilution, and after 24 hours approached control levels. Changes at this time seemed to be independent from the course of the hematocrit. It is concluded that LMW HES does not adversely influence the spleen dependent phagocytic capacity of the RES system.