Stability of prothrombin time and activated partial thromboplastin time tests under different storage conditions

2000 ◽  
Vol 300 (1-2) ◽  
pp. 13-21 ◽  
Author(s):  
L.V Rao ◽  
A.O Okorodudu ◽  
J.R Petersen ◽  
M.T Elghetany
2009 ◽  
Vol 21 (5) ◽  
pp. 674-678 ◽  
Author(s):  
Stefania Casella ◽  
Claudia Giannetto ◽  
Francesco Fazio ◽  
Elisabetta Giudice ◽  
Giuseppe Piccione

The aim of the present study was to assess the effect of different storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen concentration in clinical samples from healthy horses. A total of 100 healthy horses of varying breeds and gender, ranging in age from 4 to 18 years, with a mean body weight of 480 + 70 kg, were used. Blood was collected by jugular venipuncture, and a hemochrome-cytometric examination was conducted on all samples. All blood samples were centrifuged and divided into 4 different aliquots to assess clotting parameters by means of a coagulometer. The first aliquots were analyzed 1 hr after collection, the second aliquots were refrigerated at 8°C for 6 hr, the third aliquots were frozen at −20°C for 24 hr, and the fourth aliquots were frozen at −20°C for 48 hr. Significant differences ( P < 0.05) were determined by one-way analysis of variance with repeated measures, and statistical analysis showed a significant effect of the experimental conditions on all parameters studied. In particular, the results demonstrated that coagulation tests can be done within 6 hr when samples are stored at 8°C because the short-term refrigeration does not change the result of analyses; storage at −20°C is acceptable only after 24 hr for PT, aPTT, and fibrinogen measurements because after 48 hr, freezing alters the values of clotting parameters. Therefore, the results of this investigation indicate that clotting parameters remain stable only up to 24 hr in horses without adversely affecting hemostasis test results.


Author(s):  
Э.М. Гаглоева ◽  
В.Б. Брин ◽  
С.В. Скупневский ◽  
Н.В. Боциева ◽  
Т.В. Молдован

Цель исследования - изучить состояние системы гемостаза при хронической интоксикации хлоридом никеля, исследовать взаимосвязь показателей гемокоагуляции с процессами липопероксидации у крыс в эксперименте. Методика. Опыты проводили на крысах-самцах Вистар (n=50, 230-250 г). Раствор NiCl2 (5 мг/кг) вводили внутрижелудочно ежедневно в течение 2 нед, 1 и 2 мес. По завершении эксперимента исследовали состояние тромбоцитарного и коагуляционного звеньев гемостаза, антикоагулянтную и фибринолитическую активность крови, а также определяли активность процессов перекисного окисления липидов и антиоксидантных ферментов. Результаты. Установлено, что через 2 нед и 1 мес интоксикации у крыс отмечались гиперкоагуляционные изменения показателей свертывающей системы крови: повышение агрегационной активности тромбоцитов, увеличение концентрации фибриногена, снижение активированного частичного тромбопластинового времени (АЧТВ) и протромбинового времени. В этот период регистрировалось увеличение антитромбиновой и фибринолитической активности крови. Через 2 мес наблюдалось подавление активности клеточного звена гемостаза - тромбоцитопения, ослабление степени АДФ-индуцируемой агрегации тромбоцитов. Выявлялась тенденция к уменьшению концентрации фибриногена. На фоне снижения АЧТВ и тромбинового времени отмечалось увеличение протромбинового времени. В то же время регистрировалось угнетение противосвертывающего звена системы гемостаза (снижалась активность антитромбина III), наблюдалось истощение резервных возможностей фибринолитического звена (замедление фXIIа-зависимого эуглобулинового лизиса) и увеличение содержания растворимых фибрин мономерных комплексов, что свидетельствует о наличии тромбинемии. Через 2 нед, один и два месяца интоксикации у животных выявлялись корреляционные связи между основными показателями системы гемостаза и активностью процессов перекисного окисления липидов и антиоксидантных ферментов. Заключение. Полученные данные подтверждают наличие взаимосвязи активности процессов липопероксидации и системы гемостаза, в том числе при хронической никелевой интоксикации. Результаты исследования позволяют рекомендовать применение антиоксидантов для разработки способов коррекции гемостатических сдвигов при воздействии на организм тяжелых металлов. The aim. To study the state of the hemostasis system in chronic nickel intoxication and to investigate the relationship between hemocoagulation indices and lipoperoxidation processes in rats. Methods. Experiments were carried out on male Wistar rats (n=50, 230-250 g). A solution of nickel chloride (5 mg/kg) was administered daily intragastrically for two weeks, one and two months. At the end of the experiments, indices of platelet and coagulation hemostasis systems, anticoagulant and fibrinolytic activity of blood plasma, and activities of lipid peroxidation and antioxidant enzymes were studied. Results. Hypercoagulative changes in indices of the coagulation system were observed in rats after two weeks and one month of intoxication, including increased platelet aggregation and fibrinogen concentration and shortened activated partial thromboplastin time and prothrombin time. During the same period, increased antithrombin and fibrinolytic activities were observed. The depressed activity of the cellular component of hemostasis evident as thrombocytopenia and impaired ADP-induced platelet aggregation was detected after two months of intoxication. A tendency to decrease in fibrinogen concentration was observed. The shortened activated partial thromboplastin time and thrombin time were associated with prolonged prothrombin time. At the same time, inhibition of the anticoagulant component of hemostasis (decreased antithrombin III activity), exhaustion of the fibrinolysis system reserve (delayed fXIIa-dependent euglobulin lysis), and a significant increase in soluble fibrin monomeric complexes indicative of thrombinemia were observed. After two weeks, one and two months of nickel intoxication, a correlation was found between the major indices of the hemostasis system and the activities of lipid peroxidation and antioxidant enzymes. Conclusion. The study confirmed a relationship between the lipid peroxidation activity and the hemostasis system, specifically in chronic nickel intoxication. This result allows to recommend the use of antioxidants in developing methods for correction of hemostatic induced affected by heavy metals.


1984 ◽  
Vol 12 (01n04) ◽  
pp. 116-123 ◽  
Author(s):  
Jih-Pyang Wang ◽  
Mei-Feng Hsu ◽  
Che-Ming Teng

Bleeding time in rats was markedly prolonged after the adminstration of the water extract of Hsien-Ho-T'sao. This antihemostatic effect was more marked in the group of i.p. injection of the drug than in the group of p.o. administration for 2 to 7 consecutive days. Blood coagulation studies showed that plasma prothrombin time, activated partial thromboplastin time and stypven time were prolonged, while thrombin time adnd fibrinogen level were not changed. The thromboelastographic recording showed that reation time was prolonged and maximal elasticity of clot was decreased. In addition, ADP- and collagen- induced aggregations of platelet-rich plasma was suppressed. In conclusion, the prolongation of the bleeding time might be due to both anticoagulant and antiplatelet action of the drug.


2021 ◽  
Vol 121 (1) ◽  
pp. 22-31
Author(s):  
Alіna Baylo ◽  
Vadym Shypulіn ◽  
Volodymyr Chernyavskyi ◽  
Luiza Parunyan

The comorbid course of liver cirrhosis and atrial fibrillation causes higher levels of hospitalizations, mortality and ischemic stroke. According to current data, hemostasis in patients with liver cirrhosis is in a rebalanced dynamic state, but there are no data on the effect of atrial fibrillation on the hemostasis in patients with liver cirrhosis. Aims of the study. To assess abnormalities in primary, secondary haemostasis and fibrinolytic system in patients with liver cirrhosis and atrial fibrillation by using standard laboratory coagulation parameters and to investigate their changes depending on the stage of liver cirrhosis A, B, C according to Child-Pugh score. Materials and methods. A cross-sectional prospective study was conducted with the inclusion of 106 patients aged 42 to 83 years: group I (n = 70) - with liver cirrhosis and atrial fibrillation, II (n = 36) - with liver cirrhosis, which were distributed depending on the Child-Pugh score stages of cirrhosis and 20 healthy individuals. The levels of platelets, activated partial thromboplastin time, international normalized ratio, prothrombin time, thrombin time, fibrinogen, D-dimer were assessed on a Steellex M200 coagulometer. Statistical analysis (IBM SPSS Statistics) was performed. Results. The level of platelets in patients of group I was reduced by 37.4% (200 ± 8.33 vs. 274.7 ± 3.4; p,000.001), an activated partial thromboplastin time was prolonged by 38.6% (44.35 ± 1.39 vs. 32.01 ± 0.63, p˂0.001), prothrombin time was prolonged by 73.5% (19.4 ± 0.87 vs. 11.18 ± 0.53, p˂0.001), thrombin time was prolonged by 2.07 (25, 7 ± 1.31 vs. 12.4 ± 0.66, p˂0.001), the international normalized ratio was increased by 24.3% (1.38 ± 0.04 vs.1.11 ± 0.01, p˂0.001) compared to control. The fibrinogen level was 20.9% higher (4.17 ± 0.17 vs. 3.45 ± 0.11, p˂0.001) than in control group and was 83.7% higher (4.17 ± 0.17 vs. 2.27 ± 0.13, p˂0.001) than in group II. The D-dimer level was 83% higher than in control (675 ± 22.3 vs. 368.8 ± 21.85, p˂0.001) and 44% higher (675 ± 22.3 vs. 469 ± 37.18, p ˂0.001) compared with group II. Conclusions. In patients with liver cirrhosis and atrial fibrillation abnormalities of primary hemostasis are detected due to decrease of platelets on the background of portal hypertension. At the secondary stage of hemostasis indicators of external and internal coagulation mechanisms are prolonged due to the reduced synthesis of coagulation factors by the liver. Increased level of fibrinogen is determined at the stage of compensated and subcompensated cirrhosis with a gradual decrease at the stage of decompensation. The high activity of the fibrinolytic system is observed due to increase in the D-dimer levels, which may indicate a prothrombotic state in these patients.


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