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 +/- .15 X 10(10) per liter of blood processed (LBP) were obtained. When HES was used on only the first three passes, the subsequent three passes, done with Anticoagulant Citrate Dextrose Solution USP Formula A (ACD-A); Fenwal Laboratories, Deerfield, IL), reduced the yield to 0.14 +/- .06 X 10(10)/LBP. Reversing this procedure gave yields of 0.06 +/- .05 X 10(10)/LBP (without HES) and 0.49 +/- 0.36 X 10(10)/LBP when HES was added during the next three passes. When the HES dose was reduced to half-strength on the second consecutive day of leukapheresis, the granulocyte yields were reduced from 0.57 +/- .15 X 10(10)/LBP to 0.42 +/- .07 X 10(10)/LBP. Use of half-strength HES on virgin donors gave yields of only 0.35 +/- .39 X 10(10)/LBP. Infusion of the entire 500 ml dose of HES 1/2 hour prior to the procedure produced low yields of 0.20 +/- .12 X 10(10)/LBP, indicating that HES must be present during the centrifugation and separation procedure in order to enhance yields. The 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 six percent solution is used during the collection procedure.