A nurse is preparing to collect a capillary blood specimen from the heel of a 4-month-old infant. Which of the following actions should the nurse take?

Capillary blood sampling in infants is commonly performed to obtain small blood volumes for laboratory testing. The procedure requires careful technique to minimize pain, prevent tissue injury, and ensure an adequate specimen. In infants younger than 1 year, the heel is the preferred site due to its accessibility and lower risk of complications when used correctly. Proper site selection and technique are essential to avoid damage to underlying structures such as bone and nerves. Rationale: A. Applying a cool pack to the heel prior to the procedure is not appropriate because cold causes vasoconstriction, which can reduce blood flow and make it more difficult to obtain an adequate sample. Warmth is preferred to promote vasodilation and improve capillary blood flow for easier collection. B. Using a surgical blade to obtain the specimen is incorrect because lancets, not surgical blades, are used for capillary blood sampling. Surgical blades are too invasive and increase the risk of injury, infection, and excessive tissue damage in infants. C. Puncturing the outer aspect of the heel is correct because this area avoids injury to the calcaneus bone and underlying structures. The lateral or medial plantar surface of the heel is recommended to ensure safe and effective capillary blood collection in infants. D. Wiping the site with alcohol after the puncture is not appropriate because alcohol should be allowed to air dry before puncture to reduce infection risk and prevent hemolysis of the sample. After puncture, gentle pressure and appropriate cleansing with gauze are preferred rather than applying alcohol to an open site.