RBC mechanical fragility as a direct blood quality metric to supplement storage time.

Abstract

Lengthy storage times and associated storage lesion can result in reduced red blood cell (RBC) efficacy, particularly dangerous for massively transfused patients. Today's inventory management makes storage times the de-facto metric of blood quality. However, RBC units' quality may vary because of time-independent factors. Mechanical fragility (MF) of RBC, reflecting sub-lethal cell damage, can potentially provide a more physiologically relevant predictor of cell's performance "in vivo." Mechanical stress was applied using a bead mill (50 Hz) over durations varying from 0.5 to 60 minutes, or using ultrasound (40 W) with durations from 0.1 to 120 seconds. MF profiles were described in terms of percentage hemolysis following stresses of specified durations. RBC MF declined significantly in the presence of albumin, with albumin protecting membrane against damage from elevated temperature or from methyl-β-cyclodextrin or diamide. MF profiles allowed detection of sub-lethal membrane damage caused by elevated temperature, to a greater extent than was reflected by autohemolysis. Different types of profiles for RBC damage were associated with MF changes at different stress intensities and potentially stress types. These findings indicate that MF profiles can provide a powerful and versatile tool for investigation of RBC, as well as a potential metric of RBC quality.