Collection ProceduresQuestion 6 of 100
Which needle gauge range is standard for routine adult venipuncture with an evacuated tube system?
a.21 to 23 gauge
b.18 to 20 gauge
c.16 to 18 gauge
d.25 to 27 gauge
Explanation
Gauges 21 to 23 are standard: 21 is the general-purpose size, 22 is used for smaller or fragile veins, and 23 is typical of a winged (butterfly) set. Larger bores such as 16 to 18 gauge are used for blood donation or infusion and are unnecessarily traumatic for diagnostic draws. Very small bores like 25 gauge force cells through a narrow lumen and cause hemolysis.
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