How It Is Done

Blood sample from a vein

The health professional drawing blood will:

• Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
• Clean the needle site with alcohol.
• Put the needle into the vein. More than one needle stick may be needed.
• Attach a tube to the needle to fill it with blood.
• Remove the band from your arm when enough blood is collected.
• Put a gauze pad or cotton ball over the needle site as the needle is removed.
• Put pressure to the site and then a bandage.

Blood sample from a heel stick

During newborn testing, the blood sample is usually taken from your baby's heel (called a heel stick).

• Your baby's heel is cleaned with alcohol and then the heel is poked with a small needle.
• Several drops of blood are collected inside circles on a special piece of paper.
• When enough blood has been collected, a small bandage is put on the site.

How It Feels

The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.

Your baby may feel a sting or a pinch with a heel stick.

Risks

Blood sample from a vein

There is very little chance of a problem from having blood sample taken from a vein.

• You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for several minutes.
• In rare cases, the vein may become swollen after the blood sample is taken. This problem is called phlebitis. A warm compress can be used several times a day to treat this.
• Ongoing bleeding can be a problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can make bleeding more likely. If you have bleeding or clotting problems, or if you take blood-thinning medicine, tell your doctor before your blood sample is taken.

Blood sample from a heel stick

Usually, there are no problems from a heel stick. A small bruise may develop. Babies with bleeding problems may bleed more with usual. Sometimes bleeding problems are found when blood is being collected for the sickle cell test.

Results

A sickle cell test is a blood test done to screen for sickle cell trait or sickle cell disease.

In babies, a sickle cell blood test may be repeated at 6 months old, or a genetic information (DNA) test may be done.