Blood test: prothrombin time (PT)
What is a blood test?
A blood test is when a sample of blood is drawn for analysis in a laboratory. Doctors order blood tests to check things like glucose, hemoglobin, or white blood cells in the blood. This can help detect problems, such as an illness or medical condition. Sometimes blood tests can help them see how well an organ (such as the liver or kidneys) works.
The prothrombin time (PT) test measures the time it takes for a clot to form in a blood sample. Clotting ability is essential to prevent excessive bleeding. There are some proteins (called clotting factors) that are essential for the blood to clot well. If there is not enough clotting factor, or if one of them is not working the way it should, it may take longer than usual for the clot to form.
Why is this test done?
PT is done to evaluate bleeding problems. Your child may have this test if he has had a lot of bruising or bleeding if he has a medical condition that can cause clotting problems, if he is going to be operated on, or if he is going to have a procedure that may cause bleeding. . The PT test is also done to determine the level of clotting in children who are taking blood-thinning medications.
How should we prepare for the test?
Your child can eat and normally drink unless another test is also required at the same time that he requires prior fasting. Tell your child’s doctor about any medications because some medications can influence the test results.
Wearing a short-sleeved shirt on the day of the test can make things easier for your child; They can also carry a toy or book to distract them.
How is the test done?
In most blood tests, a sample of blood is drawn from a vein. For this purpose, a health professional:
Clean the skin places a rubber band (tourniquet) around the area to make the veins swell with blood. inserts a needle into a vein (usually in the arm, either on the inside of the elbow or on the back of the hand) Insert the blood sample into a vial or syringe. remove the gum and remove the needle from the vein
In infants, blood can be drawn from a heel stick. After cleaning the area, the healthcare professional will make a small puncture in the baby’s heel with a tiny needle (or lancet) to collect a small blood sample.
Taking a blood sample only causes the discomfort of a temporary nature, and all you feel is a brief pinprick.
Can I be with my child during the test?
Parents can often stay with their children during blood tests. Try to get your child to relax and tell him to stay very still because tight muscles can make it difficult to draw blood. Your child may want to look away from the needle when inserted into the skin and when the blood is drawn. Please help your child relax by taking deep breaths or singing her favourite song.
How long does the test last?
Most blood tests only take a few minutes. Sometimes it can be complicated to find a vein, so your healthcare professional may have to try it more than once.
What happens after the test?
The healthcare professional will remove the rubber band and needle and then cover the area with a cotton ball or plaster to stop the bleeding. After removal, a small bruise may appear, which should disappear in a few days.
When will the results be ready?
Blood samples are processed using a machine, and the results can take anywhere from a few hours to a day to be ready. If the test results indicate a possible problem, the doctor will order other tests to find out what the problem is and how to treat it.
Is the prothrombin time test associated with any risks?
The prothrombin time test is considered a safe procedure and is associated with minimal risks. Some children get dizzy or faint when blood is drawn. A few children and teenagers are terrified of needles. If your child is anxious, talk to his doctor before testing about making the procedure easier.
It is common for a small bruise and mild muscle pain to appear in the puncture area, which may last a few days. Get medical help if the mYour child’s discomfort or discomfort gets worse or lasts longer.
If you have any questions about the prothrombin time test, speak with your child’s doctor or the professional who will be doing the blood draw.
The average time for blood to clot ranges from 10 to 13 seconds. A higher number means it takes longer for blood to clot. A lower number means that the blood is clotting faster than average.
As an international normalized index
This index, which makes it easier to compare results from different laboratories, is used if you take blood-thinning medications.
For healthy people, an international normalized ratio of 1.1 or less is considered normal. An international normalized ratio between 2.0 and 3.0 is usually adequate for people taking warfarin for conditions such as atrial fibrillation or a blood clot in the leg or lung. You may need a slightly higher international normalized ratio in certain situations, such as when you have a mechanical heart valve.
If the rate is higher than the recommended range, it means that your blood is clotting slower than desired; on the contrary, your blood clots faster if the rate is lower.
Meaning of your results
Clotting too slow.
Too slow blood clotting may be due to the following:
Anticoagulant medications. Liver problems Inadequate levels of proteins cause blood to clot. Vitamin K deficiency. Other substances in the blood interfere with the work of clotting factors.
Clotting too fast.
Blood clotting too fast may be due to the following:
Supplements that contain vitamin K. High intake of foods that contain vitamin K, such as liver, broccoli, chickpeas, green tea, kale, turnip greens, and products that contain soy. Medications that contain estrogen, such as birth control pills and hormone replacement therapy.