Monitoring of RBC rheology after cryopreservation to detect autologous blood doping in vivo? A pilot study.

Background: Autologous blood doping (ABD) is applied to improve performance capacity. ABD includes blood donation, red blood cell (RBC) storage at -80°C and re-infusion prior to or during competition. ABD is not directly detectable with current detection techniques.
Objective: Since cryopreservation is known to affect RBC physiology in vitro, the aim of the study was to examine whether these alterations are detectable in vivo.
Methods: Blood from six healthy male donors was transferred into conventional blood bags, cryopreserved, stored for 18 weeks at -80°C and re-infused with a RBC volume corresponding to ∼4% of total blood volume into respective donor. RBC physiology parameters were measured before blood donation/re-infusion, and 0/1/2/6/24/48/72 h and 1 w post re-infusion.
Results: RBC parameters and age markers were unaffected during intervention. RBC deformability increased from pre-blood-sampling to pre-re-infusion while deformability and viscosity values remained unaltered post re-infusion. RBC nitric oxide associated analytes, metabolic parameters and electrolyte concentrations remained unaffected.
Conclusions: The data of this pilot study indicate that the increase in RBC deformability might be related to neoformation of RBC after blood donation. The lack of changes in tested parameters might be related to the low re-infused RBC volume which might explain differences to in vitro results.