When is capillary blood collection preferred over venipuncture?

Capillary blood collection is preferred over venipuncture primarily for infants or when veins are difficult to access due to several key reasons. Infants, particularly newborns, have small blood volumes and fragile veins that can be easily damaged during a venipuncture. Capillary blood collection, which involves pricking the skin (usually on the heel or fingertip), offers a less invasive and safer means of obtaining blood samples in these cases.

Additionally, in situations where a patient's veins are hard to visualize or palpate, capillary collection provides a viable alternative. It is a quicker and less traumatic procedure, making it suitable for these specific populations and situations.

This method is not commonly preferred for routine blood tests due to the potential for contamination and less accurate results compared to venous blood, which can be critical for diagnosing certain conditions. Emergency situations may also warrant the quick access provided by capillary collection; however, it is not exclusively limited to emergencies and is often used in a broader range of clinical scenarios involving infants or difficult access situations.