Which of the following needles should a phlebotomist use for a venipuncture using a winged infusion set and a 5 mL syringe?

While an 18-gauge needle allows for rapid blood flow, it is generally too large for most venipuncture applications, particularly when a smaller gauge is preferred for patient comfort. Using this size can lead to unnecessary trauma to the vein and discomfort for the patient, making it less ideal for routine blood draws.

A 25-gauge needle is smaller than recommended for venipuncture and may result in a slower blood draw, increasing the likelihood of complications such as hemolysis. Although it may be comfortable for the patient, the diminished blood flow can extend the time needed to collect samples, which is not ideal for a 5 mL syringe.

Similar to the 25-gauge, the 27-gauge needle is even smaller and would further decrease blood flow, making it impractical for venipuncture with a 5 mL syringe. The reduced size increases the risk of hemolysis and would likely prolong the collection process, causing patient discomfort and inefficiency.