Alternate dosage regimens for high-molecular-weight hydroxyethyl starch.

Six percent high-molecular-weight hydroxyethyl starch (HES) was used in the standard 500-ml dose and in various decreased doses to assess the efficacy of alternate dosage regimens for granulocyte procurement. When used in full strength, yields of 0.57 +/- 0.15 X 10(10) per 1 of blood processed (LBP) were obtained. When HES was used in only the first three passes, the subsequent three passes, done with acid-citrate-dextrose, Formula-A (ACD-A, Fenwal Laboratories, Deerfield, IL), reduced the yield to 0.14 +/- 0.06 (mean +/- SD) X 10(10) per LBP. Reversing this procedure gave yields of 0.06 +/- 0.05 X 10(10) per LBP (without HES) and 0.49 +/- 0.36 X 10(10) per LBP when HES was added during the next three passes. When the HES dose was reduced to one-half strength on the second consecutive day of leukacytapheresis, the granulocyte yields were reduced from 0.57 +/- 0.15 X 10(10) per LBP to 0.42 +/- 0.07 X 10(10) per LBP. Use of one-half strength HES on first-time donors gave yields of only 0.35 +/- 0.39 X 10(10) per LBP. Infusion of the entire 500-ml dose of HES one-half hour prior to the procedure produced low yields of 0.20 +/- 0.12 X 10(10) per LBP, indicating that HES must be present during the centrifugation and separation procedure in order to enhance yields. These data suggest that alternate dosage regimens of this form of HES are not advisable and that optimal yields are produced when 500 ml of the 6 percent solution is used during the collection procedure.