It's in the blood tests

Mar 2, 2014

Getting blood work done can tell a patient a lot of things. With thousands of different tests available, it can be the answer that unlocks a certain medical ailment. After a patient gives blood though, where does that blood go and what is done with it? How exactly does drawing blood tell us what is going on with our bodies?

This week on Take Care, Anne Marie Mullin talks about the basics of blood work. Mullin is senior vice president of Laboratory Alliance, a state-licensed lab that provides testing to a 16-county region in central New York. She was trained at the National Institute of Health, and is board certified in transfusion medicine.

Click 'Read More' to hear our interview with Anne Marie Mullin.

One of the first things patients notice when getting blood work done is the variety of different colored caps used to cover collection tubes. Each color says something unique about the specimen that tube will carry.

“Those caps indicate what is or is not in that tube itself. Some tests are performed on whole blood, so the specimen will be drawn into a tube that keeps that blood from clotting. Other tests are performed on the serum. There are different chemicals in those tubes that allow certain tests to be performed and other tests not to be performed,” says Mullin.

Some labs, like Laboratory Alliance, have over 1,500 tests that can be done. Different tests need to be done more quickly than others. How quickly does it have to get to the lab?

“Depending on the test, it determines how quickly that specimen needs to get to the laboratory. A test, for example if a doctor is looking to perform a pneumonia level, that test needs to get to the laboratory expeditiously, within a short period of time.”

The way the vials of blood are stored before testing is also determined on the kind of test that is going to be conducted.

“Some tests can only be performed on a specimen that’s kept protected from light, because light might degrade the substance that we’re looking to measure. Some tests can only be performed at ambient or room temperature. Others have to be kept refrigerated, and some other tests have what is known as critical processing, and perhaps we need to quickly process that tube and freeze it,” said Mullin.

Sometimes technicians have trouble finding a patient's vein. If that happens to you, is there anything you can do to make it easier?

“Keeping yourself properly hydrated will allow the tissue and the area around the vein to be in a better state so that you can ascertain that vein and quickly go in and draw that patient’s specimen," said Mullin.

A phlebotomist may also warm the arm or ask the patient to make a fist and pump their arm. Those motions just moves the muscle and the tissue around where the veins are so the veins are a little more visible.

For patients with thinner, smaller veins, a different procedure may be needed.

“We will use what is known as a butterfly needle. It’s a little bit thinner, but it’s also a little bit trickier for the phlebotomist to collect the blood specimen because it’s coming out of a very narrow piece of tubing into the tube,” said Mullin.