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.
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.
University of Texas Medical Branch, Galveston, TX, USA mafoshat@utmb.edu yoqian@utmb.edu.
Michelle
M
Foshat
University of Texas Medical Branch, Galveston, TX, USA.
Stephanie
S
Bates
University of Texas Medical Branch, Galveston, TX, USA.
Wendy
W
Russo
University of Texas Medical Branch, Galveston, TX, USA.
Araceli
A
Huerta
University of Texas Medical Branch, Galveston, TX, USA.
Kathleen
K
Albright
University of Texas Medical Branch, Galveston, TX, USA.
Karen
K
Giddings
University of Texas Medical Branch, Galveston, TX, USA.
Alexander
A
Indrikovs
University of Texas Medical Branch, Galveston, TX, USA.
You-Wen
YW
Qian
D020016:Activated Protein C Resistance / Q000097:blood* / Q000175:diagnosis; D001774:Blood Chemical Analysis / Q000379:methods*; D001778:Blood Coagulation Disorders / Q000097:blood / Q000175:diagnosis; D001780:Blood Coagulation Tests; D001800:Blood Specimen Collection / Q000379:methods*; D016022:Case-Control Studies; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D005615:Freezing; D006801:Humans; D010314:Partial Thromboplastin Time; D011517:Prothrombin Time; D012016:Reference Values; D013696:Temperature; D013997:Time Factors
D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D
    d-dimer; APCR; DRVVT; PT; aPTT; coagulation; preanalytical variables