Effect of freezing plasma at -20°C for 2 weeks on prothrombin time, activated partial thromboplastin time, dilute Russell viper venom time, activated protein c resistance, and d-dimer levels

Michelle Foshat, Stephanie Bates, Wendy Russo, Araceli Huerta, Kathleen Albright, Karen Giddings, Alexander Indrikovs, You-Wen Qian

Research output: Contribution to journalArticle

4 Scopus citations


To assess the impact of preanalytical variables of time and temperature on prothrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russell viper venom time (DRVVT), activated protein C resistance (APCR), and d-dimer, samples from 23 healthy individuals and 18 patients having coagulopathy with known abnormal PT and aPTT were collected. Plasma from each individual was separately pooled and aliquoted; the first 2 aliquots were stored at room temperature then analyzed at 2 hours (baseline) and 4 hours postcollection. The remaining aliquots were stored at -20°C and thawed for analysis at 48 hours, 1, and 2 weeks. In both healthy participants and participants with coagulopathy, PT, aPTT, APCR, DRVVT, and D-dimer had no significant changes at 4 and 48 hours, and 1 and 2 weeks postcollection compared to baseline, or the changes were less than 10%. The results indicate PT, aPTT, DRVVT, APCR, and d-dimer can be stored for 2 weeks at -20°C without compromising clinical interpretation in both healthy individuals and individuals with coagulopathy. Increasing storage time will facilitate sample processing from off-site clinics.

Original languageEnglish (US)
Pages (from-to)41-47
Number of pages7
JournalClinical and Applied Thrombosis/Hemostasis
Issue number1
StatePublished - Jan 4 2015



  • APCR
  • aPTT
  • coagulation
  • d-dimer
  • preanalytical variables
  • PT

ASJC Scopus subject areas

  • Hematology

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