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How to Have a Stress Free Blood Draw
Your Doctor has given you orders to have your blood drawn for testing. You will be visiting a hospital laboratory where a phlebotomist will perform the procedure. At this point you will have one of several emotional responses, mostly based on experience, which range from casual acceptance, minor anxiety, a lot of anxiety or fear. Here are a few explanations about what will happen when you have your blood drawn. Knowing what to expect can help alleviate some of the anxiety.
The Doctor's Orders
You have been given orders for specific tests to be run on samples of your blood. The orders may not make a lot of sense to you, but there are some things that you should look for on the order form.
- Read them thoroughly before going to have your blood drawn.
- Has the Doctor written any special instructions such as fasting for a period of time before the blood draw?
- Has the doctor indicated that copies of results should be sent to another doctor? If so, point this out to the laboratory staff.
- Has the doctor requested a urine sample as well as the blood draw? You'll want to be aware of this beforehand so you are ready to provide the sample.
Blood draw with vacutainer from antecubital region
Butterfly tubing and needle
The Blood Draw
If you have had your blood drawn many times, you are probably aware of where on your arm the lab personnel have had success. Feel free to share this with the person drawing your blood, especially if it has been difficult to find a good vein in the past.
If you have not had your blood drawn often, you may experience anxiety about the procedure. Here are some things you can do to relieve stress as well as a description of the simple procedure.
- Be calm and relaxed. Bring something interesting to read while you are in the waiting room.
- If you are anxious, close your eyes and take a few deep breaths before entering the lab and just before the procedure.
- Engage the lab person in casual conversation to set a calm, comfortable atmosphere.
- The rubber strap or tourniquet around the upper arm restricts blood flow and allows the veins to fill up and stand out. This helps the lab person find the best vein.
- The area around the vein is cleansed with an alcohol pad.
- The needle is inserted and the tubes are filled. Pick something in the room to watch at this point so that you aren't tempted to watch the procedure take place.
- The tourniquet is released.
- The needle is withdrawn.
- Gauze or a cotton ball is placed over the puncture. Apply firm pressure even if the lab person places a bandaid or tape over the cotton ball. This will prevent or at least reduce bruising.
The Blood Tubes
Don't be concerned about how much blood is taken. Each tube holds just a few milliliters. Barcode labels will be placed on the tubes identifying them as yours. The different colors of tube tops indicate specific types of testing for the blood that goes into them.
- Blue is for coagulation studies.
- Lavender is for a variety of cell counts.
- Green is for blood chemistry studies.
- Gold or red tube tops mean that the blood will be allowed to clot so that the serum can be studied without the blood cells and clotting agents.
- Gray is for glucose.
Common Blood Tests
Here are a few of the most common tests done on blood.
Complete Blood Count or CBC-
- Red blood cells carry oxygen.
- White blood cells fight infection.
- Hemoglobin is the oxygen-carrying protein in red blood cells
- Hematocrit is a measurement of the amount of red blood cells compared to the amount of fluid, known as plasma, in your blood.
- Platelets help blood to clot.
- Sodium helps regulate water in the body and in the transmission of electrical signals.
- Potassium regulates heart beat. Low potassium can cause muscle cramps.
- Chloride helps maintain fluid balance
- Bicarbonate helps to regulate acid in the body's tissues.
Blood urea nitrogen (BUN) is a kidney function test.
Creatinine is also a kidney function test.
Glucose is the body's primary source of energy. High blood glucose, or hyperglycemia, can be a symptom of diabetes. Low blood glucose is known as hypoglycemia.
Red Blood Cells
Having Your Blood Drawn Can Be a Positive Experience
A visit to the laboratory for a blood draw does not have to be a negative experience. If you understand what the procedure entails and what your doctor is testing you for, it can be a very positive experience.