Determining the effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration in rat plasma samples

Abstract

Coagulation parameters are usually included in clinical and preclinical safety studies to evaluate the effect of xenobiotics on the extrinsic or intrinsic pathways of coagulation. The analysis is generally performed at the time of terminal sacrifice where many activities are scheduled. Chances of delay in analysis are likely particularly when blood is collected for coagulation via the abdominal vena cava. This experiment was planned to assess the variations in coagulation parameters caused by delay in analysis as well as by storage conditions. Blood was collected from the posterior vena cava under isoflurane anesthesia, and the plasma was separated immediately. Coagulation parameters were evaluated at 0, 6, 24 and 48 h from the plasma stored at room temperature, as well as plasma stored under refrigerated and freezing conditions. Stability of the analytes in blood was also evaluated under refrigerated conditions for 6 h. All parameters were analyzed using a semi-automated coagulometer. Prothrombin time (PT) was stable under all three storage conditions for up to 6 h. Although statistically significant differences were observed for activated partial thromboplastin time (APTT) at room and refrigeration temperatures for up to 6 h, the difference was clinically non-relevant. Fibrinogen was found to be the most stable parameter that showed consistency in results even up to 48 h under all three storage conditions. Plasma for PT can be stored and analyzed without any significant changes for up to 6 h from the actual blood collection, while fibrinogen level testing can be extended for up to 48 h after collection under any storage condition. For reliable APTT results, plasma samples should be run immediately after collection.

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

“…Our finding is also at variance with a previous report which indicated that prothrombin time and APTT results are stable for up to 24 h and 8 h respectively, remaining constant regardless of storage conditions [10]. Also, Goyal and colleagues [11] evaluated coagulation parameters (PT and APTT) at 0, 6, 24 and 48 h from the plasma stored at room temperature, as well as plasma stored under refrigerated and freezing conditions and observed that PT can be stored and analysed without any significant changes for up to 6 h from the actual blood collection, while for APTT results, plasma samples should be run immediately after collection. Our finding is consistent with previous report [12] which reported that PT and APTT can be reliably tested after storage for 8 h at room temperature and that the acceptable time interval can easily be extended to 24 h for PT determination.…”

Changes of hematological references depends on storage period and temperature conditions in rats and dogs

“…For rat blood samples, plasma should be run immediately after collection for reliable activated partial thromboplastin time results [3]. For dog blood samples, differences in white blood cell (WBC) and platelet (PLT) counts varied with the specimen [4].…”

Interference With Coagulation Cascade as a Novel Approach to Counteract Cisplatin-Induced Acute Tubular Necrosis; an Experimental Study in Rats

“…Prothrombin time and Ptt were measured according to the method described by Goyal et al (2015) using a CoaDATA automated analyzer (Ahrensburg, Germany) according to the manufacturer’s instructions.…”