NHA Certified Phlebotomy Technician (CPT)Collection RoutineMedium
A phlebotomy technician is collecting blood using a winged infusion set (butterfly needle) for a patient with small, fragile veins. Which of the following angles of insertion is most appropriate for this device?
- A10- to 15-degree angle
- B90-degree angle
- C45-degree angle
- D30-degree angle
Show answer & explanationAnswer & explanation
Correct answer: A. 10- to 15-degree angle
Winged infusion sets are typically used for superficial veins and require a shallower angle of insertion (10-15 degrees) compared to straight needles. This angle helps to prevent puncturing through the fragile vein and reduces the risk of hematoma formation.
Why the other options are wrong
- B. A 90-degree angle is used for intramuscular injections, not venipuncture.
- C. A 45-degree angle is too steep for superficial veins and risks going through the vein.
- D. A 30-degree angle is common for standard venipuncture with straight needles but may be too steep for fragile veins with a butterfly.
Winged Infusion Set Angle
The optimal angle of needle insertion when using a winged infusion set (butterfly needle), typically shallower than standard venipuncture, to accommodate superficial and fragile veins.
- Used for small, fragile, or rolling veins.
- Commonly used for pediatric and geriatric patients.
- Shallower angle (10-15 degrees) reduces risk of vein perforation.
- Allows for greater flexibility and control during collection.
Memory trick: ANGLE Precision: Always Nudge Gently, Low Entry.