Relative Viscosity and Specific Gravity of Human Blood During Cold Storage

Abstract

Summary

Eight units of blood were preserved under blood banking conditions for a period of 42 days. Aliquots were assayed for relative viscosity, specific gravity, and density distribution of red cell population at the time of collection of blood, at 21 and 42 days of storage. Relative viscosity demonstrated an exponential, and specific gravity a linear, relationship with red blood cell mass, measured as hematocrit content. The three parameters investigated showed significant changes during the preservation of blood. The magnitude of these changes is greater between 21 and 42 days than between 0 and 21 days of storage. Red cells from fresh blood were separated into two extreme age groups, low density (young) and high density (old cells); the osmotic fragility of the erythrocytes in these two groups was different and the high density cells demonstrated greater osmotic resistance than cells from 42-day-old blood.