Intravenous (IV) Therapy: Venipuncture using an Over-the-Needle Catheter
In medicine, venepuncture, venopuncture or venipuncture is the process of obtaining intravenous access for the purpose of intravenous therapy or obtaining a sample of venous blood. This procedure is performed by medical laboratory scientists, medical practitioners, some EMTs, paramedics, phlebotomists, dialysis technicians and other nursing staff. Venepuncture is one of the most routinely performed invasive procedures and is carried out for two reasons, to obtain blood for diagnostic purposes or to monitor levels of blood components (Lavery & Ingram 2005). Blood analysis is one of the most important diagnostic tools available to clinicians within healthcare. Its data is relied upon in the clinical setting for interpretation of a myriad of clinical signs and symptoms and developing skills in venepuncture can facilitate holistic and timely treatment.
Blood is most commonly obtained from the median cubital vein, which lies within the cubital fossa anterior to the elbow. This vein lies close to the surface of the skin, and there is not a large nerve supply.
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.
Phlebotomy (incision into a vein) is also the treatment of certain diseases such as hemochromatosis and primary and secondary polycythemia.
-excerpt from wikipedia