Influence of Time and Temperature on Coagulation Analytes in Stored Plasma

Abstract

There is no comprehensive study on the stability of coagulation analytes in plasma. We therefore determined the influence of storage time and temperature on prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, factors V and VIII, antithrombin III, protein C and S in plasma from 20 healthy subjects and 20 patients receiving heparin therapy. The stability in plasma, defined as the period during which there was a change of less than 10% from the initial value, was 8 hours for activated partial thromboplastin time, 24 hours for prothrombin time, 48 hours for factor V and 7 days for thrombin time, fibrinogen, protein C and antithrombin III in healthy subjects at 6 degrees C. Factor VIII and protein S showed 19 and 12 % reduction in activity, respectively, after 8 hours. In volunteers not treated with heparin therapy, activated partial thromboplastin time was stable for 8 hours; prothrombin time for 48 hours; and thrombin time, fibrinogen and antithrombin III for 7 days with sample storage at room temperature. Factor VIII showed a decrease of 18 % after 8 hours. For patients receiving heparin therapy, the stability of the analytes in plasma stored at 6 degrees C was 8 hours for thrombin time, 24 hours for prothrombin time and activated partial thromboplastin time and 7 days for fibrinogen and antithrombin III. Factors V and VIII showed a decrease of 13 % and 20 % respectively after 8 hours. When the plasma of these patients was stored at room temperature, factor V was stable for 8 hours, and prothrombin time for 24 hours, whereas fibrinogen and antithrombin III remained unchanged for 7 days. Activated partial thromboplastin time showed an increase of 13 %, thrombin time a fall of 16 %, and factor VIII a decrease of 18 % after 8 hours.

The Effect of Time and Temperature Variables on Some Routine Coagulation Tests among Subjects of African Descent in Sokoto, North Western Nigeria

“…Previous report indicated that APTT measurements were increased at 4˚C while PT measurements were decreased at 4˚C [23]. Similarly, Heil and colleagues [24] demonstrated that APTT samples were stable up to 8 h at either RT or 4˚C, except for those which were on unfractionated heparin therapy. Several studies recommended that PT and APTT determinations may be constant for periods more than currently suggested in NCCLS guidelines [25] [26].…”

Laboratory hemostasis: milestones in Clinical Chemistry and Laboratory Medicine

“…In 1998 Heil et al carried out an influential study that is still the basis for several guidelines and recommendations about coagulation testing [59] . Basically, the authors determined the influence of storage time and temperature on PT, APTT, thrombin time (TT), fibrinogen, factors V and VIII, antithrombin, protein C and S in plasma from healthy subjects and patients receiving heparin therapy.…”

Einfluß der Citratkonzentration im Blutentnahmeröhrchen auf hämostaseologische Meßgrößen. Influence of the Sample Tube’s Citrate Concentration on Coagulation Analytes

“…Heil [3] Im Lichte unserer Fragestellung gilt es auch, das Citrat/P/ajwfl-Volumenverhältnis näher zu betrachten. Wir beschrieben für Globalteste jüngst eine Hyperkoagulabilität bei einem Citrat/Blut-Volumenverhältnis von 1:14 und eine Hypokoagulabilität bei einem Verhältnis von unterhalb l: 9, erfolgte die Abnahme in 0,109 mol/1 Natriumcitrat und war der Hämatokrit mit 45 % (0,45) "normal".…”

“…Citratplasma für Gerinnungsanalysen war Gegenstand verschiedener Arbeiten der vergangenen Jahre [1][2][3][4][5]. Die Ergebnisse zeigten teilweise deutliche Differenzen, sowohl bei unterschiedlichen Testverfahren als auch bei gleichen Testverfahren mit Reagenzien verschiedener Hersteller [l, 3,4]. In anderen Arbeiten wurde der Einfluß von Über-oder Unterfüllung des Entnahmeröhrchens auf Gerinnungsteste untersucht [5,6].…”