What Are Sodium Citrate Tubes? Uses, Types, Benefits and How They Work

If you need blood work done at a hospital or clinic, you may see the nurse or lab tech using different colored tubes to get your sample. Each tube is used for a different test and has different additives that help with those tests. It is the sodium citrate tubes that is used most often.

A lot of medical tests use these tubes, especially to check how well your blood clots. We’ll talk about what sodium citrate tubes are, how they work, the different kinds that are out there, and what they’re used for in this post. Don’t worry, it will be simple and simple to follow.

What Is a Sodium Citrate Tube?

A sodium citrate tube is a type of blood collection tube used in medical labs. It contains a clear solution of sodium citrate, which acts as an anticoagulant. An anticoagulant is a substance that prevents blood from clotting too soon.

The tube is usually light blue in color, which makes it easy for healthcare professionals to recognize.

When your blood is drawn into this tube, the sodium citrate binds to calcium in your blood. Calcium is one of the main elements that helps blood clot. By tying up the calcium temporarily, sodium citrate keeps the blood in liquid form until the lab is ready to test it.

Why Sodium Citrate Is Used in Blood Collection

Keeping Blood From Clotting During Tests

Sodium citrate is mostly used to stop blood from clotting before the test starts. If the blood in the tube clots, it can’t be used to test for clotting diseases, problems with bleeding, or even to keep an eye on medicines that thin the blood.

Keeping Blood Components Stable

With sodium citrate, blood is kept steady so that it can be tested correctly in the lab. This means that doctors can rely on the data to help them diagnose or treat their patients.

How Sodium Citrate Tubes Work

Here’s a step-by-step look at what happens when blood is drawn into a sodium citrate tube:

• Blood enters the tube – The medical professional fills the tube to the right amount after blood goes into it.
• Sodium citrate mixes with blood – The solution inside immediately reacts with calcium.
• Clotting is delayed – Since calcium is tied up, clotting cannot occur in the tube.
• Lab testing begins – When it’s time to run tests, the lab can add calcium back in. This lets them measure exactly how long clotting takes or see how well blood-thinning medications are working.

So, sodium citrate doesn’t destroy clotting factors. It just “pauses” them until the lab is ready to measure.

Common Uses of Sodium Citrate Tubes

Sodium citrate tubes are essential for several medical tests. Here are the main areas where they’re used:

1. Studies of Coagulation

Sodium citrate tubes are a key part of tests that check how quickly or slowly blood clots.

Some of these are:

• Prothrombin Time (PT) : It is a way to check how quickly blood clots and is often used to keep an eye on people who take blood thinners like warfarin.
• APTT, or “Activated Partial Thromboplastin Time,” : Helps find problems with blood clotting.
• The International Normalized Ratio (INR) : Standardizes PT results across different labs.

2. Monitoring Blood-Thinning Therapy

Individuals taking blood-thinning drugs, known as “anticoagulants,” need regular testing. Doctors use sodium citrate tubes to find out exactly how these drugs work and make sure the dose is safe and right.

3. Finding Disorders That Cause Bleeding

Some people’s blood clots differently because of conditions they were born with or later got. Labs can use sodium citrate tubes to help them find diseases like hemophilia and von Willebrand disease.

4. Screening Before Surgery

Doctors may want to check a patient’s blood to make sure it will clot properly before, during, and after surgery. Use sodium citrate tubes to collect blood for these regular checks.

Different types of Sodium Citrate Tubes

Salt citrate tubes are not all the same. They are different based on the type of closing system and the amount of blood to anticoagulant.

1. Tubes with 3.2% sodium citrate

• This is the type that people use most often today.
• The solution consists of 3.2% sodium citrate.
• Most current test tools can use it to get correct data.

2. Tubes with 3.8% sodium citrate

• It has a 3.8% solution in it.
• These days, labs use them less frequently, but some may still rely on them for certain tests.

3. Different Sizes

There are different sizes of sodium citrate tubes:

• 2 mL, 3 mL, 4.5 mL, or 9 mL, based on what the test needs.
• Versions specifically designed for kids are also available.

4. Vacuum tubes vs. non-vacuum tubes

• Vacuum tubes take out just the right amount of blood on their own.
• Fill non-vacuum tubes by hand, as you only use them in specific situations.

Also Read : Blood Collection Tubes Manufacturers: The Complete Guide

Benefits of Using Sodium Citrate Tubes

Using sodium citrate tubes offers several important benefits in healthcare:

Accurate Testing

Sodium citrate tubes keep blood from clotting too soon. This helps labs run tests correctly. Accurate results are very important because doctors use them to understand a patient’s health.

Safety for Patients

These tubes are safe for patients because they contain the right amount of sodium citrate. The chemical is gentle and does not harm the blood. This makes the testing process safer and more reliable.

Easy Handling in Labs

Sodium citrate tubes are simple for lab workers to use. The tubes are ready with the right amount of solution, so there is less chance of mistakes. The testing process goes more smoothly and quickly this way.

Preserves Sample Quality

The sodium citrate keeps blood cells in good condition. This means the sample stays fresh and useful for longer. Samples of good quality help doctors figure out how to treat patients better.

Proper Use and Handling of Sodium Citrate Tubes

To get accurate test results, healthcare workers must follow strict guidelines when using sodium citrate tubes.

The right fill volume

Fill the tube all the way to the marked line. The amount of citrate to blood can go wrong if there is too little or too much blood.

Mixing gently

After taking the blood, turn the tube upside down a few times to mix the blood with the citrate. Using too much force can hurt blood cells.

On-Time Testing

Speedily send samples to the lab. When there are delays, clotting factors can change, which can lead to wrong results.

Proper Storage

Store the tubes at the recommended temperatures and use them before their expiration date.

The Difference Between Sodium Citrate Tubes from Other Tubes

Sodium citrate tubes may seem different from other usual blood collection tubes.

EDTA Tubes

• Purple top tubes contain EDTA, another anticoagulant.
• Used mainly for complete blood counts (CBCs).
• Not suitable for clotting studies because EDTA binds calcium too strongly.

Also Read : EDTA Blood Tube: Why It’s the Standard for CBC Testing

Heparin Tubes

• Green top tubes contain heparin.
• Often used for plasma chemistry tests.
• Not recommended for coagulation tests.

Serum Tubes

• Red or gold top tubes contain no anticoagulant (or clot activator).
• Use when serum is need for testing.
• Blood clots inside, opposite of what’s need for clotting studies.
• This comparison shows why sodium citrate tubes are the standard for coagulation testing.

Why Sodium Citrate Tubes Are Important in Healthcare

In medicine, it’s easy to forget how important little tools like these are. Without sodium citrate tube, however, doctors would find it hard to:

• Find trouble with bleeding or clots,
• Handle people who are taking blood thinners safely,
• Make sure that surgeries don’t cause unexpected blood,
• Give correct test data for treatments that could save lives.

These little light-blue tubes are very important for everyday health care.

Final Thoughts

Sodium citrate tube might look like ordinary medical supplies, but it very important in healthcare. They stop blood from clotting too quickly, which helps doctors get accurate test results. These tubes come in different sizes and strengths, and using them correctly helps keep patients safe and healthy.

Doctors use sodium citrate tube to check for problems with blood clotting, watch how well blood-thinning medicines are working, and get patients ready for surgery. So next time you see a light-blue tube during a blood test, remember that it plays a big role in keeping people healthy.