Unit 3: Routine Venepuncture

• Topic 01

  Patient Identification — Two-Identifier Protocol and Wristband Verification

  45 questions
• Topic 02

  Evacuated Tube System — Components, Vacuum, and Tube Holders

  45 questions
• Topic 03

  Syringe Collection Technique and Transfer to Tubes

  45 questions
• Topic 04

  Butterfly (Winged Infusion) Set — Indications and Technique

  45 questions
• Topic 05

  Order of Draw — Rationale and Tube Additive Interactions

  45 questions
• Topic 06

  Tourniquet Application and Release Timing

  45 questions
• Topic 07

  Vein Palpation and Site Selection

  52 questions
• Topic 08

  Needle Insertion Angle and Bevel Orientation

  45 questions

A few questions from this unit, with the answer and a full explanation. The complete bank is available when you start practising.

1. What is the consequence of drawing the EDTA tube before the chemistry (gold/green) tube?

   • A
     The EDTA causes the SST gel to migrate incorrectly, invalidating the serum separation
   • B
     The chemistry tube fills with a partial clot because EDTA prevents proper clotting in all subsequent tubes
   • C
     EDTA carryover falsely lowers calcium and may elevate potassium in the chemistry specimen, producing critical result errors
     Correct answer
   • D
     The EDTA tube fills with SST additive, causing haematology results to be invalid
   Explanation

   EDTA carried over from the lavender tube into the gold or green tube introduces calcium-chelating activity into the chemistry specimen. The most significant consequences are (1) falsely decreased ionised calcium (EDTA binds free calcium) and (2) falsely elevated potassium (K2EDTA introduces potassium ions). Both of these represent clinically dangerous false critical values. The gel separator in an SST tube does not protect against additive carryover from the needle tip piercing the stopper. CLSI GP41-A7 identifies this as a high-priority order-of-draw violation.

2. A patient insists on removing their wristband because it is uncomfortable, and removes it before the phlebotomist arrives. The patient says 'I know who I am, just draw my blood.' How should the phlebotomist respond?

   • A
     Proceed and document that the patient refused to wear the wristband in the collection notes
   • B
     Ask a family member present to confirm the patient's identity and proceed with their confirmation
   • C
     Explain to the patient that a wristband is required for inpatient identification, call the nurse to reapply the wristband, and do not draw until it is replaced
     Correct answer
   • D
     Accept the patient's verbal identification plus the room number as the two required identifiers
   Explanation

   Patient comfort preferences do not override the hospital identification protocol. A wristband is required for inpatient identification. The phlebotomist should explain the reason for the requirement (patient safety), request the nurse reapply the wristband, and not draw until this is done. The phlebotomist does not have the authority to waive the wristband requirement unilaterally. This is consistent with TJC NPSG.01.01.01 and hospital CMS Conditions of Participation compliance.

3. A competency evaluator notes that a phlebotomy student consistently inserts butterfly needles at 20–25 degrees on hand veins and at 15 degrees on antecubital veins. What should the evaluator document?

   • A
     Correct technique: insertion angle is standardised at 15–30 degrees for any venepuncture device
   • B
     Incorrect technique only for the antecubital angle; 20–25 degrees on hand veins is within the acceptable butterfly range
   • C
     Incorrect technique: butterfly angle on hand veins should be 10–15 degrees; the student is using angles that are too steep for superficial veins and too shallow for antecubital veins
     Correct answer
   • D
     Partially correct technique: 15 degrees for antecubital veins is within range but butterfly needles should not be used on antecubital veins at all
   Explanation

   For hand veins, the butterfly insertion angle should be 10–15 degrees — shallower than antecubital access because these veins are more superficial. Using 20–25 degrees on a hand vein risks through-puncture. For antecubital veins (if a butterfly is used), 15 degrees is at the lower end of the acceptable ETS range but appropriate for a butterfly on a relatively superficial antecubital vein. The evaluator should specifically flag the too-steep angle on hand veins as a patient safety risk. CLSI GP41-A7 is the reference standard for insertion angle competency evaluation.