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Venipuncture

What is venipuncture?

Venipuncture is a medical procedure in which a needle is used to take blood from a vein, typically for laboratory testing. This procedure is also called phlebotomy or blood draw.

During the procedure, the site is first cleaned with an antiseptic and an elastic band is placed around the upper arm, causing the vein to swell. A needle is then inserted into the vein, drawing blood into a vial or tube attached to the needle. Once the collection is complete, the elastic band is removed, and the needle is taken out.

For young children and infants, a doctor may perform a venipuncture by using a lancet to puncture the skin and collecting the blood onto a test strip or slide.

Most blood tests do not require special preparation beforehand. However, some may require the patient to fast or stop taking certain medications prior to the procedure.
 

Why is venipuncture important for healthcare?

Blood is composed of fluid (plasma or serum) and cells, and healthcare providers gain valuable information about a patient’s health by collecting the blood and analyzing these components.

The information gained from the venipuncture procedure depends on the type of blood test completed. A basic metabolic panel, for instance, offers insights into a patient's fluid balance and levels of electrolytes, while a lipid panel measures the presence of fat molecules like cholesterol and triglycerides.