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Just a basic medical science question. Is a vacutainer necessary for use in venous whole blood sample collection? Also is the needle with plastic holder required? Can we not draw blood using a sterile syringe and place it into containers? Convenience and efficiency aside, is it considered a requirement? In the Wikipedia article, it says that the traditional method of drawing blood is with a syringe and needle. However, that doesn't explain the need for EDTA, citrate and heparin additives in the tubes.

Kate Gregory
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Nederealm
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  • I've edited the question to reflect additional information in my findings – Nederealm May 01 '20 at 17:14
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    @Nederealm Doesn't that article you've linked already do a pretty good job of explaining it? It talks about what the additives are, what they do, and for what purposes those are used. Can you explain which part is still unclear to you? – Bryan Krause May 01 '20 at 17:22
  • Is the use of such containers mandatory to get accurate results? – Nederealm May 02 '20 at 17:09
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    I'm curious about the motivation behind your question. Additives increase manufacturing costs, so why do you think manufacturers would add them if they weren't important? – Carey Gregory May 03 '20 at 23:04

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These additives are required to get correct results. They keep the blood from clotting. If blood is collected with a syringe, clotting factors will activate and this will give inaccurate results for clottingfactors and platelets, and possibly other tests as well.

ThomasMellen
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    Welcome to Medical Sciences! We work differently than most SE sites in that we have a strict policy that all answers should be backed up with reliable references so that the answer can be independently verified regardless of the reader's background. See this list of reliable sources. If you still have trouble with this, feel free to visit the [help] or [meta]. Unreferenced claims can lead to answers being deleted. – Carey Gregory May 03 '20 at 21:18
  • So certain test do not work with capillary blood sampling like those do it at home test kits? – Nederealm May 05 '20 at 09:15
  • Sorry, can't accept your answer @Carey explanation that information has to be backed by reliable references. Anyway, I up voted due to your effort to explain in simplest non-medical terms as possible – Nederealm May 05 '20 at 09:45
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The article you linked calls those three additives anticoagulants, and provides a link to a page on that. It starts:

Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time.

If you put blood in a glass tube, or most plastic tubes, it clots to a solid quite quickly. (A few minutes on glass at body temperature.) This makes it impossible to test for anything related to clotting (since those factors may have been used up) and frankly difficult to test for anything else because you have a blob of jelly or even something the consistency of cheese, so you can't pour it, stir a reagent into it, and so on.

To overcome this difficulty, someone went to a lot of trouble to invent a tube that would keep air out, and would have specific additives in it that wouldn't themselves interfere with the testing. I expect the exact details of how much of each additive, which tests are still accurate with heparin and which are not, which are ok with EDTA and which are not, and so on, would fill a book. For the purposes of your question, we can say yes, the additives are necessary for some tests, and that is why people use them.

Kate Gregory
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