This is from Azevlab227:
Good afternoon, George. I have a question for you and I’m hoping that other regular contributors to the site will have comments as well. I am currently using the VerifyNow P2Y12 for identifying those patients who are sensitive to the antiplatelet effect of Plavix or Prasugrel. There is a push to bring platelet mapping into the lab because there is a perceived problem with the measurement system of the cartridges, specifically at hematocrits less than 30%.
Hello and thank you for your question. You are correct that according to Accumetrics, the VerifyNow P2Y12 assay is not indicated when the hematocrit (HCT) is below 30%. However, you may wish to look into the effect of hematocrit on any other method you may choose. For instance, PFA-100 manufacturers set a HCT limit of 33%, and instruments like the TEG may be affected as well.
Dave McGlasson sent me the following hemodilution information from Elaine Haney atHaemoscope:
Greetings, I have looked up our hemodilution interference testing results for kaolin activated TEG. We tested normal donor blood that was diluted ex-vivo with 0.9% saline to the following levels: 0% (blank), 10%, 20%, 30%, 40%, 50% (i.e., ½ saline and ½ blood). The results showed that the concentration at which hemodilution first became an interferent (showed a statistical and clinically significant difference from control in TEG parameters) was 40% dilution. I hope this helps.
Warm Regards, Elaine I. Haney, BS, MT; R&D Associate; Haemoscope Division
No comments here.