What is capillary puncture primarily used for?

Capillary puncture is primarily used for collecting small amounts of blood, specifically for pediatric testing or when venipuncture is not feasible. This method involves pricking the skin, usually on a finger or heel, which allows for the collection of a few drops of blood. It is particularly useful for infants and young children, where minimizing discomfort and risk is a priority. Additionally, capillary samples are often sufficient for various tests such as glucose monitoring or hemoglobin levels.

In contrast, blood transfusions require a significant volume of blood that cannot be obtained through capillary puncture, thus making it unsuitable for that purpose. Similarly, capillary puncture does not lend itself to collecting large volumes of blood quickly, which would be necessary for extensive laboratory testing. While capillary punctures can be used to test for infections, they are not primarily designed for that purpose, especially when larger blood samples are often required for accurate infection screening and diagnosis.