Viability of glycerolized red blood cells frozen in liquid nitrogen.

Abstract

Freeze‐preservation of human red blood cells with a low concentration of glycerol (approximately 20 per cent w/v), liquid‐nitrogen refrigeration, and a stainless steel container was evaluated by measurements of the posttransfusion survival of 10‐ml samples of 51chromium‐labeled autologous red blood cells, together with several measurements in vitro. Removal of glycerol prior to transfusion (the major technologic problem) was carried out both by serial centrifugation (batch washing) and by continuous centrifugation, using either predilution or sequence wash cycles. A biologic product of glycerolized red blood cells was prepared to the following specifications: the recovery in vitro of at least 90 per cent of the red blood cells after thawing and washing was achieved, together with 24‐hour posttransfusion survival in vivo of approximately 85 per cent, a total amount of supernatant hemoglobin in the unit on the day of washing of approximately 450 mg, a preparation time of approximately 30 minutes, and a total volume of wash solution of less than 3.0 liters. The present urgent need in frozen blood preservation is for systems which use disposable software in a completely automated wash cycle.