Final answer:
A skin puncture for an adult or older child typically involves using a sterilized lancet on the fingertip, after cleansing with an alcohol swab, to obtain a blood sample for various tests.
Step-by-step explanation:
When performing a skin puncture on an adult or older child, typically a sterile, sharp lancet is used to puncture the skin to obtain a small blood sample for testing. The most common site for skin puncture is the fingertip, particularly the side of the fingertip, as the skin is thinner there and it is less painful than other areas. However, alternative sites such as the earlobe or heel (in infants) may be used depending on the procedure and patient condition. It is crucial to clean the puncture site with an alcohol swab before performing the puncture to reduce the risk of infection and to ensure that the first drop of blood is wiped away to avoid contamination with tissue fluids. The lancet should be used in a swift, smooth motion to minimize discomfort and obtain an adequate sample. This procedure is often used for blood glucose tests, hemoglobin tests, and other similar diagnostic assessments.