Table of Contents
Introduction
Did you know that if you get a cut, scrape, or any type of injury, your body does something cool to help you? Your blood makes a clot, which stops the bleeding! Clotting stops the blood from coming out and helps protect the site from germs, heals the wound, and even keeps your body’s fluid balanced. Pretty amazing, right?
So, how does this clot happen?
When bleeding, tiny cells called platelets rush towards the spot where you are hurt. These platelets stick together to form a plug. Then, special proteins called the clotting factors jump in to help. They make a fibrin mesh that holds everything together and strengthens the clot.
But did you know sometimes a person's blood doesn't clot as fast as it should? This can cause more bleeding and other complications, which is not good. So, how do doctors check if your blood is clotting correctly? They use the partial thromboplastin time test, or PTT test. This tells doctors how long it takes for your blood to clot.
Let's find out how this test works, who needs it, what the risks are, and what the results mean.
What Is a Partial Thromboplastin Time Test?
PTT is a special type of blood test that checks how long it takes for the blood to clot and how well your clotting factors are working. Doctors use this test to determine whether someone has a bleeding issue or whether certain medications, like anticoagulants, are working correctly. PTT has other names, too! Some call it activated partial thromboplastin time (aPTT) or intrinsic pathway coagulation factor profile, which all mean the same.
What Is Measured in a Partial Thromboplastin Time Test?
PTT checks how long your blood takes to clot. But guess what? It does even more than that! Let's have a look.
When bleeding, several steps are involved in making a stable clot. This is called the coagulation cascade (which includes intrinsic and common pathways). It is like a domino falling, where one step triggers the next. PTT checks how well these steps are working.
PTT checks how well the proteins called clotting factors are working.
PTT checks why the blood is taking too long to clot.
Some people take medications called blood thinners to reduce clot formation and prevent strokes and heart attacks. PTT makes sure that the medicines are working fine or require any adjustments.
Did you know that your liver makes many clotting factors? The PTT also checks whether the liver is healthy.
Why Does One Need a Partial Thromboplastin Time Test?
PTT is a super helpful test. Your doctor may suggest this test for a few reasons, like
Diagnosing Bleeding Disorders: PTT can help diagnose the cause of bleeding and determine if any clotting factors are missing. Therefore, it helps diagnose bleeding problems like hemophilia, von Willebrand disease, etc.
Monitor Anticoagulant Therapy: If someone takes Heparin, a blood thinner, PTT can help check if the medicine works well. And based on the results, doctors can even adjust the dose.
Accessing Liver Function: As said before, the liver produces most of the clotting factors, like factors I, II, V, VII, IX, X, XI, and XII, along with proteins C and S. The PTT test can give doctors a clue about how your liver is doing.
Others: Sometimes, the PTT test can also help doctors diagnose autoimmune disorders like antiphospholipid syndrome (where the immune system mistakenly attacks phospholipids, causing an increased risk of blood clots). Doctors may also ask you to do a PTT test before surgeries to make sure your blood clots properly and won’t bleed during the operation.
When Is a Partial Thromboplastin Time Test Done?
The doctors might ask for a PTT test if:
You are bleeding a lot, and no one knows why.
Your blood is clotting too quickly.
You are getting blood clots in places they shouldn’t be.
You had more than one miscarriage.
You have liver issues.
You are taking medicines to thin the blood.
You are undergoing surgery.
How Does a Partial Thromboplastin Time Test Work?
In this test, special substances are added to start the clotting process, and then the time it takes to clot is measured.
Let's see step by step.
First, the nurse takes a blood sample from your arm. The blood then goes into a special tube containing citrate, which stops the blood from clotting.
At the laboratory, centrifugation separates the plasma (the watery part that forms 55% of the total blood).
Then, special reagents are added to the plasma. These include calcium and an activator like ellagic acid or kaolin. These reagents trigger intrinsic and common pathways.
After that, they measure how long it takes for the clot to form.
How Should One Prepare for a Partial Thromboplastin Time Test?
Getting ready for the PTT test is easy. But you should tell the doctor a few things.
Let your doctor know if you take any medicines, especially blood thinners.
Let your doctor know if you are taking any herbal medicines, too.
Let your doctor know if you have any clotting issues.
Try not to smoke or drink alcohol 24 hours before the test.
What Happens During the Partial Thromboplastin Time Test?
The PTT test is straightforward and quick.
Here’s what happens:
First, the nurse will clean the spot (arm vein) where the blood will be taken.
A stretchy band, called a tourniquet, may help make your veins easier to see.
Then, a small needle is gently inserted to collect blood. You may feel a pinch or a sting when the needle goes in. The blood then goes inside a tube containing an anticoagulant.
Afterward, they might put a bandage on the spot.
The whole thing takes less than 5 minutes.
What Happens After a Partial Thromboplastin Time Test?
After the nurse takes your blood, you may be asked to press the spot to stop bruising. You can then go back to your normal activities. Depending on the place, results may be available within a few hours to a few days. Later, the doctor will explain the results to you.
Is There Any Risk to the PTT Test?
The PTT test is safe. But just like other tests, there may be small risks like
Bruising or bleeding.
There may be a tiny chance of infection if sterile technique is not used.
Sometimes, blood may accumulate under the skin, which is called a hematoma.
A few people may feel dizzy or faint, especially if they are nervous about the test.
Sometimes, they may try to find the spot more than once.
What Do the Results of the Partial Thromboplastin Time Test Mean?
Here’s what the PTT test results mean:
Normal PTT: Usually, the blood clots in about 25 to 35 seconds.
Prolonged PTT: Prolonged or high PTT can be caused by bleeding problems like hemophilia, clotting factor deficiency, liver disease, vitamin K deficiency, an autoimmune disorder, a type of blood cancer called leukemia, or anticoagulant medications (the dose is high). Treatment for high PTT depends on its cause.
Shortened PTT: Shortened or low PTT can be due to inherited clotting disorders, autoimmune disorders, or certain cancers (ovaries, pancreas, or colon). It can also happen in the early stage of disseminated intravascular coagulation (DIC), a rare condition. Low PTT can increase the chance of forming clots.
Conclusion:
So, PTT is a special type of test that helps doctors check how long it takes your blood to clot. It’s not just for finding bleeding disorders; it can also help determine how your liver is functioning and help make sure your blood thinner medicine is the correct dose. This test is quick and easy and takes only 5 to 10 minutes. Along with other health tests, PTT can help doctors diagnose and treat appropriately.
Keynote from iCliniq
The PTT is a quick and safe test that takes only a few minutes. How fast you get the result depends on the laboratory. If you or your loved ones have bleeding issues or need help understanding the results, doctors at iCliniq are always there to help you.
