Many people are afraid of doing blood tests because they believe that it hurts. There are also many people who are not afraid of doing blood tests and have had many experiences where a blood draw didn’t hurt. So, do blood tests hurt?
A blood draw may or may not hurt. Sometimes a blood draw hurts and sometimes it doesn’t. If a blood test is done properly and everything goes well it really shouldn’t hurt. There may be a small sting when the needle pierces the skin but that’s about it.
Therefore, some people may experience some pain while others may not. Here are 11 reasons why some blood tests may hurt.
11 Reasons Why Some Blood Draws Hurt
- The Patient Moves his/her Arm when the Needle is Inserted into the Vein or while the Needle is in the Vein
Usually, at the start of the procedure, a person is given a few instructions with regard to doing the blood test. One of these instructions is to keep the arm steady and stable for a fast and safe venipuncture. This simple rule is very crucial to the procedure. It helps with locating, stabilizing, and puncturing the vein. Thus, a simple move of the arm will cause the vein to move.
If the arm is moved when inserting the needle, then the needle could miss the vein, puncturing nearby tissues or nerves causing pain. If the arm is moved while the needle is in the vein, then the needle could go through the vein also puncturing nearby tissues causing pain and bruising.
This is often seen with children. More often than not, children will move their arm when doing a blood test. Occasionally, it happens with older children and adults.
2. The Depth of the Vein
Some people have superficial veins while some other people’s vein is deeper and more difficult to find and puncture. Superficial veins are easy to find, stabilize, and poke. Deep veins can be more troublesome. Because they are deeper, more of the needle has to go into the arm to puncture the vein which may definitely cause some hurt.
3. The Location of the Vein being Punctured
There are about 3 main areas where blood is drawn for blood tests. The antecubital fossa which is usually the first choice for finding a vein, houses the median cubital vein, cephalic vein and basilic vein. The other 2 areas used are down the forearm and at the bank of the hand.
The median cubital vein is probably the site where the least amount of pain is felt since it is easy to access. It is often big, straight, easy to find and has fewer nerve endings. The cephalic and basilic veins are the next choices. In some individuals it may be easier finding the cephalic or basilic vein than the median cubital vein. However, it may be more painful puncturing one of these veins since there are more nerve endings surrounding them.
Drawing blood from the back of the hand or the forearm is also painful for the same reason.
4. The Force and Angle of Insertion
The needle is inserted into the vein at a 30-15 degree angle. The puncturing of the vein should be gentle, smooth, and without force. By force I mean the patient shouldn’t have to say the poke was hard. In order words, if it is done with ease and lightness the patient may not feel any pain.
Also, I think puncturing the vein below 15 degrees may increase pain.
5. Loose Skin (skin not taut/not anchoring the vein)
Pain may be felt if the phlebotomist does not taut the skin and anchor the vein before inserting the needle into the vein. When the skin is loose or is not stretched or tight, piercing the skin will hurt more.
6. Size of Needle
Three gauges of needles are commonly used to draw blood, the 21, 22 and 23 gauges respectively. For persons with difficult veins a 24 or 25 gauge may be used. The higher the gauge number the smaller the needle and the lower the gauge number the bigger the needle.
Personally, I don’t know if the sizes of needles make a difference in how much pain is felt. I haven’t tried it on myself to know for sure but many persons have hinted that it does. On occasion, a patient will ask me to use a smaller size needle instead of a bigger one when am drawing their blood. Usually, they ask for the 23 gauge since it’s smaller. They claim that it hurts less.
I remember this patient asking me to use the smallest needle that was available. I replied and told her, her vein was big enough for a big needle. Of course, we talked kindly. She was all laughing and I suppose she maybe feared needles slightly.
I tried to assure her that the size didn’t matter. But was I right? Maybe not! She had been poked before and she knew what she had felt. Maybe some of you feel the same way.
Maybe I could poke her with a 21 gauge needle and she may not feel any pain but this may not be the case every time and for every phlebotomist.
What am saying is I don’t know if the size of the needle matter per say. However, if people feel that it does, then I assume they are right.
7. The Size of the Person’s Vein (small, thin)
Many adults have small or thin veins. Children particularly have small veins. For these veins a smaller size needle is used, preferably, a 23 gauge needle or in the case of a child with very small veins, a 24 or 25 may be used.
When the veins are small it could be painful drawing blood from them.
8. Fragile Veins (elderly)
In case of the elderly, aging causes the skin to lose tone and elasticity and as a result it becomes more fragile and prune to bruising. The loss in subcutaneous tissue causes the veins to be less stable and, therefore, they easily wiggle or roll under the skin when the needle is inserted.
The skin is loose and the vein is rolling. Holding the skin down and anchoring the vein are needed for a successful draw but the process can hurt.
9. Difficult Patients (burn, oncology, some children)
Cancer patients, persons who have had burns, critical care patients, obese people and some children can pose difficulty when trying to find and hit a vein for a draw. It may be that the nurse or phlebotomist may have to stick you more than once.
10. Having Multiple Draws
Multiple draws are definitely a painful experience. It usually occur with persons who have difficult veins, although, it can happen with someone who has good veins. At the first attempt, the phlebotomist may be unsuccessful with the draw, so he or she must try again.
Several sticks definitely hurts! They may cause hematomas as well. If you ever have that experience it will hurt you a bit.
11. Missing the Vein or Going Through it
A phlebotomist may miss the vein sometimes or maybe even go through it. When that happens you may feel a sting or slight pain as the needle enters surrounding tissue or may hit a nerve.
As you have found out there are many reasons why a blood test can hurt. Notwithstanding, If the blood draw is done properly and none of the above happens then the blood test should basically not hurt except for the sting that may be felt when the needle pierces the skin.
Read 9 Tips for Easing Discomfort and Bruising after a Blood Draw.