Platelets estimation after cryopreservation Ocena krwinek płytkowych po procesie kriokonserwacji Regional Center of Blood Donation and Treatment, Katowice Head of Regional Center: Stanisław Dyląg, Pharm D, PhD

Summary Introduction. Platelet concentrates are essential for treating bleedings in patients with thrombocytopenia in order to pre- vent spontaneous hemorrhage. Platelets are also needed during invasive medical procedures. Storing their concentrates for further use can be prolonged by methods of cryopreservation. Aim. The aim of this study is to estimate whether platelet concentrates preparation methods affect the number of platelets recovered after cryopreservation. Material and methods. Analyses were carried out from June 2006 to January 2010. They included 160 platelet concen- trates, received from aphaeresis and from pooled buffy coats. Platelets concentrates were frozen in five percent dimethyl sulfoxide (DMSO) and stored at -80°C. The number of platelets was counted before freezing and after thawing using the automated haematology analyser. Results. The average recovery of thawed platelets was 73.57% - varied from 72.77 up to 74.42% depending on the applied method. The analysis did not reveal statistically significant differences in recovery between platelets from particular groups. Mean values in particular groups varied by 1.65 per cent. Median values and scope of results for particular groups were similar. Conclusions. The above analysis proves that method of obtaining of platelet concentrate has no influence over the num- ber of thawed platelets.