SHAPE CHANGE AND HYPOTONIC SHOCK RESPONSE MEASUREMENTS TO ASSESS FUNCTIONAL EFFICACY OF PLATELETS

Several variables such as anticoagulant, plastic bag composition, gas transport, residual plasma volume, agitation and storage temperature i nfluence the viability and function of platelets during storage, Measu rements of pH, pO(2) and pCO(2) are good enough to predict acid-base b alance but not for detecting functional stability of platelets, A quic k and simple screening method is required to establish the functional response of stored platelets to agonists, Minimal activation of platel ets may be a reversible change, but if they are stimulated to change s hape and secrete their granular contents, they turn nonfunctional and refractory to agonists, So refractoriness of platelets to agonist resp onse can be a reliable method to detect the functional loss of platele ts, Here it is demonstrated that refractoriness can he measured by a s imple spectrophotometric shape change measurement, Platelets that were deliberately stimulated were used as a model for refractory platelets , The data obtained for shape change response was double-checked using conventional aggregometric analysis to detect loss of function, Measu rement of hypotonic shock response to assess the post-transfusion reco very of stored platelets is also studied in unstirred suspension, usin g a double beam spectrophotometer. Thus a simple spectrophotometric an alysis will enable the transfusion centres to check quality of the sto red platelets and predict their post-transfusion recovery and hemostat ic efficacy.