I have donated my blood 3 times now...all three times at different hospitals.

The first time, a very fine needle was used...almost similar to the one usually used in injection or to draw blood for blood tests.

However, subsequently, much broader needles were used...by their looks, they seemed nearly twice as broad as the earlier needle. It also caused more pain than the first time. I guess they use the broader needle to draw blood more quickly.

However, I have noticed another phenomena...the subsequent blood donations have left a depression-type scar mark on my skin.

So I have the following questions:

  1. Am I right in concluding that a broader needle would have been used to draw blood quickly?
  2. Are the needles used to draw blood replaceable? Can I ask the nurses drawing my blood to replace the broad needle with a finer one? (I asked the nurse if it was possible and he said that as far as he knew, only broader needles came for blood donation.)
  3. If the needles are indeed replaceable, then what are they called? How should I refer to them for the nurse to be able to understand me correctly.

This information would help me donate blood relatively painlessly next time.

Thank you.

P.S.: I am not a medical profession (or even a medical student for that matter). So please pardon my complete layman-like language here.

1 Answer 1

  1. Larger needles aren't used to draw blood faster in general. They are used to avoid hemolysis. 16-18 gauge needles:

A large needle (16 to 17 gauge) is used to minimize shearing forces that may physically damage red blood cells as they flow through the needle

What may be used to speed up the process is:

  • Squeezing your fists, whether on their own or with a stress ball to squeeze (some locations instead have you roll an item back and forth in your hand to reduce arm tension)
  • Tourniquets or blood pressure cuffs
  1. Larger needles are used to stop harm from occurring to the blood cells. Some companies however do not use them due to cost and availability since they may be nonprofit. Some other occurrences are:

Needle Sizes

during blood donation a 18 gauge needle is common. If a patient has small or fragile veins, the phlebotomist often elects to use a small gauge needle.

Depressions in your arm from needle sticks

You may still experience pain. It sometimes depends on the person drawing experience level.

  • Hi, I have some follow-up questions: (1) If the probability of damaging the drawn RBCs is greater with Higher guage needles, then why are they used to draw blood for blood tests? Aren't RBCs checked during blood tests? (2) If Vitamin E cream is applied before the blood tests, won't it's effect be nullified when the Phlebotomist applies the disinfectant before drawing my blood? Is there any time prescription that it should be applied this many minutes before donating blood so that it may be fully effective? (3) Doesn't a regular hair oil (such as almond) also have Vitamin E?
    – Zuch
    Commented Apr 2, 2016 at 16:21
  • Hi @beck2ham Sorry for the late reply, but thesequestions would be to much to answer in the comments and would probably benefit from a separate answer. Thank you!
    – Pobrecita
    Commented Jun 9, 2016 at 5:10
  • 1
    I will try to add some of this to my answer though. Such as #1.
    – Pobrecita
    Commented Jun 9, 2016 at 5:13

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