Blood is drawn from a vein, most frequently from an elbow or back of a hand. After blood is drawn, the puncture site is cleaned with an antiseptic. The upper arm is wrapped in an elastic band to apply pressure to the vein and cause it to swell. An airtight vial or syringe is used to collect blood after the injection of a needle into a vein.
When the process is complete and the blood is collected, then the needle is removed, the puncture site is covered to stop bleeding, and the band is removed to allow the blood to flow again.
In the case of infants or small children, a lancet or needle is used for puncturing the area, followed by cleansing with antiseptic. During the blood draw, blood is collected by pipette, slide, test strip, or small container. In the event of bleeding, applying a bandage may be necessary to the puncture site.