Skin puncture: skin puncture is usually done when small volume of blood is needed (e.g., blood glucose test) to avoid unnecessary venipuncture.
However, skin puncture in time consuming and have greater risk of infections than venipuncture because fingertip is more difficult to sterilized than the anticubital fossa. In an adult or grown child, blood may be collected by puncturing the tip of the finger or by piercing the earlobe. In an infant of less than 1 year of age, the lateral and medial planter surface of the foot should be used for skin puncture.
Area should be sterilized by 70 % isopropanol, then all alcohol allowed to dry, and skin is quickly punctured by a lancet. Massage of the finger to stimulate blood flow should be avoided because it causes flow of debris and tissue fluid, which does not have the same composition as plasma have. Blood may be collected by a capillary blood tubes by capillary attraction. Filter paper is used for collection of capillary blood used in neonatal screening.