Which specific piece of data for blood coag?

Question

Which specific blood test data does a physician or lab tech check to verify -in layman's terms- blood "thickness" or not ?. In other words, clotting ability ?

I am totally out of my waters here.

Not a test question...I'm way past school age.

TIA !

Answer 1

"Blood thinners" - a laymans term for anticoagulating medications, are used to prevent vascular compromise as a result of unintended clotting. There are several categories of medication, and the manner in which they are monitored differs, based on the mechanism of action.

One of the most common medications used for prolonged anticoagulation is coumadin. This medicine interferes with production of specific "clotting factors" that depend on the presence of vitamin K. By blocking where vitamin K would be used in the production of these factors, the relative levels are reduced in the blood stream, and the time to form a blood clot is prolonged. Of note, increasing dietary vitamin K counteracts this medicine, while decreasing dietary intake makes the medicine more potent. Regular monitoring of the "PT" which is the "prothrombin time" is necessary to adjust dosing. In most labs, the PT result, a time expressed in seconds, is coupled with an"INR" or international ratio. The INR is nothing more than a fraction, based on the ratio of the patient's INR compared to lab standards. An INR of 1.0 is right on normal, and an INR of 2.5-3.5 is typically where people will be kept when they're therapeutic on coumadin.

The PTT, or "partial thromboplastin time" is another lab value expressed in units of seconds. It is not directly affected by coumadin administration because the test is designed to be sensitive to changes in the relative presence of a different set of clotting factors. Classic hemophiliacs will have a profoundly abnormal PTT, as will people who have received intravenous heparin, an anticoagulant given while people are in the hospital. Intravenous heparin is not typically given as a long term medication. It is given as a continuous infusion because it has a half life of only about 90 minutes. It can be given in a "low molecular weight" form as a periodic subcutaneous injection, but this is typically for the prevention of blood clots in people who are ill, and who are at risk for venous blood clots in the legs due to inactivity. LMWH unfortunately does not affect the PTT value, and cannot easily be checked for effect. In oddball cases where that would be desireable, the only lab value that is altered is something called an "activated factor ten assay" ... but thats probably more information than you need! ;)

One final class of important anticoagulants involves the anti-platelet medications. This class is especially important in people who have atherosclerosis and peripheral vascular disease. This group of patients suffers from carotid artery disease, coronary artery disease, decreased blood flow to the legs, and usually some degree of high blood pressure. In patients who develop these rough atherosclerotic plaques on the insides of arteries, there is a strong risk of small clots forming on the surfaces of plaques that subsequently break loose and float away in the blood stream, only to wedge in the later microvessels and cause damage. This is the most common mechanism for heart attack and stroke. The anticoagulants that help in this situation are anti-platelet medications.

Platelets are tiny cells which are intimately involved in clot formation. By interfering with their chemical contribution to clotting, the risk of heart attack or stroke is substantially reduced. Medications in this class include things like aspirin, plavix, and ticlid. By preventing platelet aggregation, microclots on the surfaces of ruptured plaques are prevented. These medicines do not affect either the PT or the PTT, and judging their effectiveness is much more clinical in nature. In general, the side effects such as bleeding gums and easy bruisability or even spontaneous internal bleeding are watched for. In their absence, standard dosing is followed. There does exist a study called the "bleeding time" which is substantially platelet dependent, however it is impractical to use in order to monitor anti-platelet medications. In the bleeding time study, a tiny standardized cut is made in the skin, and the time it takes to stop bleeding is recorded!

... I hope that helped!

Answer 2

PTT / INR &or PT

One is used to monitor coumadin therapy which is a blood thinner. The other I believe checks heparin therapy another blood therapy but used for short time where coumadin would be long term therapy. So PT / INR

Answer 3

Lol, that is very funny. How do you do this. You posted like over 10 questions in a row.