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Coagulation detection test

E-Zlab is specialized in blood work & medical tests at home & work.

Our team of licensed and specialized nurses can visit you at home, your business or anywhere else you chose to receive us

Prothrombin Time or Coagulation Detection Test

The prothrombin time test, better known as INR, represents the time needed for blood to coagulate. The meaning of INR is ‘international normalized ratio’. It is a uniform method that uses a blood sample to help your anticoagulotherapy treatment.

The envisaged INR, the anticoagulating treatment and its duration are set up by your physician, according to the health problem from which you are suffering.

The monitoring of your INR can be delegated to a registered nurse or to a pharmacist, with the consent of your physician against a medical prescription. Please talk to your physician or pharmacist.

Your physician can resort to anticoagulants if blood clots developed in your arteries or if your disease or condition is likely to give rise to clots in your blood.

It can be a question of :

  • Auricular fibrillation, which is a disease consisting in rapid and irregular heartbeats, likely to give rise to cerebral vascular accidents (CVA) because of the blood clots, which may block the arteries that convey the blood to the brain.
  • Mechanical heart valves, made from a material that is foreign to your body, used to treat sick valve problems. Blood clots can appear on them, thus causing shortness of breath. If one of them gets detached from the valve, it can cause a CVA.
  • Profound venous thrombosis (PVT) and pulmonary embolism. The blood clots that have developed in the deep veins of the legs can block them, which is called PVT. In rare cases they can develop in other profound veins, stay there or go toward the lung arteries, thus entailing pulmonary embolism. The cause could be a wound that damaged the vein wall or a surgical intervention. These events can stimulate coagulation and when associated to a reduction of mobility, give rise to PVT.
  • Myocardial infarction, which can render that person more exposed to the risk of new clots forming, thus causing jamming at the level of the coronary arteries or in some other arteries that convey blood to the brain. An anticoagulating treatment will be initiated if there is a high risk of pulmonary embolism.


An anticoagulotherapy can last between several weeks to several years and it is determined by your physician, according to the condition that needs treating.

It can be initiated in the hospital, when heparin is administered by subcutaneous injections (under the skin) during the first days after your arteries have been blocked by clots, as well as in case of profound venous thrombosis. Then a registered nurse form your Local Center of Community Services can go to your house for making the heparin shot once a day, for 5 to 7 days.

At that time, an oral anticoagulant is prescribed for a limited period of time by your physician, in order to avoid the formation of blood clots and any jamming of a blood vessel. The oral anticoagulants act at the synthesis of the vitamin K-dependant coagulation factors, for instance Warfarine (Coumadinmd, Taro-Warfarinmd or another make) or Nicoumalone (Sintrommd).

Blood taking for your INR needs performing once a day, at the beginning of the treatment, in order to adjust your anticoagulant dose until a therapeutic INR is obtained, then according to the frequency set up by your physician or by another health professional.

No need to have an empty stomach.

The doctor or another health professional assigned to carry out the INR for you must be informed on any situation likely to affect it (for instance you have forgotten to take your anticoagulant, you have consumed more alcohol, taken new medication, undergone dental surgery, or you are bleeding).

In certain circumstances it is important to check your INR more often (e.g. diarrhea, fever, recent surgery, disease).

If you need to undergo a surgery or a medical intervention likely to cause bleeding, the anticoagulant must be stopped a few days before that. In certain cases, the heparin injected under your skin can replace your anticoagulant.

Any anticoagulant taking must be let know to any doctor, dentist or pharmacist that you see.

The INR selected by your physician must be between 2 and 3 (2-3 times the normal value) or between 2.5 and 3.5, according to the health problem that needs treating.

We offer a quick service 7 days a week, for the INR test. The results will be ready the same day as the blood sampling.

The INR results are sent by fax to your treating physician or to any health professional responsible for carrying out your anticoagulant dosage.

You can see the list of the blood tests offered by E-ZLab and linked to the coagulation detection test :

PT INRTPT (prothrombin)Complete blood count (CBC or Complete hemogram)FibrinogenComplete hemogram or Complete blood count

Perscription & Insurance

All our tests require a medical prescription recommended by any practicing doctor in the province of Quebec.

These prescriptions are necessary in order to proceed with either test and we urge that all medical requests originating from offices or clinics be duly identified.

All medical analysis requested by your doctor are reimbursed by a majority of private insurance companies!