Circadian variation of blood clotting time and circulating vitamin K in the athletic horse

In one experiment 3 steers, 4 bull calves and 4 wether lambs were orally administered 2 milligrams dicoumarol per kilogram body weight and blood-clotting time measurements were made over a 4-day period. All animals responded to the dicoumarol but differences were evident between sheep and cattle; sheep were apparently more tolerant of the drug.The ’one-stage prothrombin’ test was more reliable and sensitive than the clotting tests employed for factor VII, factor X and prothrombin concentration.In a second experiment, 16 ewes in late pregnancy were fed rations containing 0 to 30 p.p.m. of synthetic dicoumarol and vitamin K3 as a cross treatment. Evidence of abnormal clotting power of ewe blood was observed in ewes fed diets containing 10 p.p.m. of dicoumarol. There was some indication of cumulative effects at this level after 32 days on test. At intake levels of 20 and 30 p.p.m. clotting times were affected more markedly and some ewes exhibited extended bleeding times after 2 to 4 weeks on test. No unusual hemorrhaging occurred at parturition. In general, the lambs’ blood did not reflect the pre- or post-partum dicoumarol intake of their mothers but a few lambs, as in the case of the ewes, exhibited low tolerance for dicoumarol without showing much disturbance in terms of clotting time. A large single oral dose of menadione sodium bisulphite demonstrated the effectiveness of vitamin K3 as an antidote. However, vitamin K3 as a ration supplement at 12 milligrams per pound feed failed to protect ewes against the effects of dicoumarol.

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Autoprothrombin II of human origin

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1961.201.4.660 ◽

1961 ◽

Vol 201 (4) ◽

pp. 660-662 ◽

Cited By ~ 12

Author(s):

Orhan N. Ulutin ◽

J. Frederic Johnson ◽

Walter H. Seegers

Keyword(s):

Whole Blood ◽

Blood Clotting ◽

Human Origin ◽

Clotting Time ◽

Generation Test ◽

Blood Clotting Time

Autoprothrombin II activity develops when prothrombin preparations of human origin are activated with purified thrombin at pH 8.2. Early during the activation an inhibitor seems to form. Concentrates of the autoprothrombin II can replace serum in the thromboplastin generation test provided platelets are used in the test, but not if a soy bean phosphatide is used. Dogs were given Coumadin in doses that lowered their own autoprothrombin concentration practically to zero. Then while continuing with use of the drug some purified autoprothrombin II was infused intravenously. This was tolerated very well. The autoprothrombin II concentration stayed at normal for 7 hr. In 24 hr none remained. The infusion was also followed by a shortening of the whole blood clotting time.

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Heparin Concentrations Correlated To The Activated Whole Blood Clotting Time (Act) During Extracorporeal Circulation

10.1055/s-0038-1652697 ◽

1981 ◽

Author(s):

S Stenbjerg ◽

E Berg ◽

O K Albrechtsen

Keyword(s):

Extracorporeal Circulation ◽

Whole Blood ◽

Blood Clotting ◽

Heart Surgery ◽

Open Heart Surgery ◽

Open Heart ◽

Excellent Correlation ◽

Clotting Time ◽

Automated Method ◽

Blood Clotting Time

Heparin levels and ACT were followed during open heart surgery in lo patients. Heparin was assayed by an amidolytic method using substrate S-2222. ACT was determined with an automated method using celite and glass beads as activators of coagulation. Neither the hemodilution nor the depletion of platelets observed during extracorporeal circulation seemed to influence the ACT. An excellent correlation between the ACT and the actual heparin level was found in each patient with coefficients of correlation ranging from 0.73 – 0.97. A slightly better correlation was noticed for values of ACT below 600 seconds. It was concluded that the ACT is a valuable and reliable tool in control of heparinisation during open heart surgery.

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Role of Trisodium Citrate in the Unclottability by Thrombin of Fibrinogen Metz

10.1055/s-0039-1689371 ◽

1975 ◽

Author(s):

C. Soria ◽

J. Soria ◽

M. Samama ◽

E. Poirot ◽

G. Kling

Keyword(s):

Calcium Chloride ◽

Whole Blood ◽

Blood Clotting ◽

Negative Charge ◽

Trisodium Citrate ◽

Thrombin Time ◽

Clotting Time ◽

Fibrin Formation ◽

Blood Clotting Time

In a case of homozygous dysfibrinogenemia, the whole blood clotting time was moderately prolonged, while the thrombin clotting time was infinite, whatever dose or nature of thrombin used. Besides, the bleeding syndrome in this case was very weak.We observed also that only after trisodium citrate addition to purified fibrinogen, the abnormal fibrinogen became unclottable by thrombin even after addition of calcium chloride, since without trisodium citrate thrombin time was only prolonged.By immunoelectrophoresis and by isofocusing in the presence or in the absence of trisodium citrate, we therefore undertook to show that trisodium citrate reacts more strongly with the abnormal fibrinogen than with normal one. Thus, trisodium citrate conferring a negative charge to the pathological molecule, the abnormal fibrinogen became resistant to clotting with thrombin. Protamine sulfate, by positiving the charges of fibrinogen, partially corrects the defect in fibrin formation.

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Anticlotting activity of phosvitin on chicken blood in vitro

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1962.203.6.1170 ◽

1962 ◽

Vol 203 (6) ◽

pp. 1170-1172 ◽

Cited By ~ 1

Author(s):

Koji Sato ◽

Kazutaka Homma ◽

Jiro Gotoh

Keyword(s):

Whole Blood ◽

Blood Clotting ◽

Egg Yolk ◽

Clotting Time ◽

Chicken Blood ◽

Blood Clotting Time

Phosvitin, a phosphoprotein isolated from the vitellin of egg yolk, prolonged the whole blood clotting time in the chicken blood in vitro. The degree of phosvitin's inhibition of coagulation was inversely related to the level of egg-yolk-like material in plasma induced by estrogen.

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Bedside Coagulation Tests in Diagnosing Venom-Induced Consumption Coagulopathy in Snakebite

Toxins ◽

10.3390/toxins12090583 ◽

2020 ◽

Vol 12 (9) ◽

pp. 583 ◽

Cited By ~ 2

Author(s):

Supun Wedasingha ◽

Geoffrey Isbister ◽

Anjana Silva

Keyword(s):

Low Income ◽

Whole Blood ◽

Blood Clotting ◽

Specific Treatment ◽

Small Sample ◽

Consumption Coagulopathy ◽

Clotting Time ◽

Wide Range ◽

Coagulation Tests ◽

Blood Clotting Time

Venom-induced consumption coagulopathy is the most important systemic effect of snake envenoming. Coagulation tests are helpful to accurately and promptly diagnose venom-induced consumption coagulopathy and administer antivenom, which is the only specific treatment available. However, bedside clotting tests play a major role in diagnosing coagulopathy in low-income settings, where the majority of snakebites occur. We conducted a literature search in MEDLINE® from 1946 to 30 November 2019, looking for research articles describing clinical studies on bedside coagulation tests in snakebite patients. Out of 442 articles identified, 147 articles describing bedside clotting assays were included in the review. Three main bedside clotting tests were identified, namely the Lee–White clotting test, 20-min whole blood clotting time and venous clotting time. Although the original Lee–White clotting test has never been validated for snake envenoming, a recently validated version has been used in some South American countries. The 20-min whole blood clotting time test is the most commonly used test in a wide range of settings and for taxonomically diverse snake species. Venous clotting time is almost exclusively used in Thailand. Many validation studies have methodological limitations, including small sample size, lack of case-authentication, the inclusion of a heterogeneous mix of snakebites and inappropriate uses of gold standard tests. The observation times for bedside clotting tests were arbitrary, without proper scientific justification. Future research needs to focus on improving the existing 20-min whole blood clotting test, and also on looking for alternative bedside coagulation tests which are cheap, reliable and quicker.

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