Venipuncture

In medicine, venipuncture or venepuncture is the process of obtaining intravenous access for the purpose of intravenous therapy or for blood sampling of venous blood. In healthcare, this procedure is performed by medical laboratory scientists, medical practitioners, some EMTs, paramedics, phlebotomists, dialysis technicians, and other nursing staff. In veterinary medicine, the procedure is performed by veterinarians and veterinary technicians. Venipuncture is one of the most routinely performed invasive procedures and is carried out for any of five reasons: (1) to obtain blood for diagnostic purposes; (2) to monitor levels of blood components (Lavery & Ingram 2005); (3) to administer therapeutic treatments including medications, nutrition, or chemotherapy; (4) to remove blood due to excess levels of iron or erythrocytes (red blood cells); or (5) to collect blood for later uses, mainly transfusion either in the donor or in another person.

Blood analysis is an important diagnostic tool available to clinicians within healthcare.

Blood is most commonly obtained from the superficial veins of the upper limb. The median cubital vein, which lies within the cubital fossa anterior to the elbow, is close to the surface of the skin without many large nerves positioned nearby.

Minute quantities of blood may be taken by fingersticks sampling and collected from infants by means of a heel stick or from scalp veins with a winged infusion needle.

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