and Answers | Graded A+ | Update
Section 1: Blood Collection Procedures (26 Questions)
1. A phlebotomy technician is selecting a site for venipuncture on a patient with a right
mastectomy. Which site should the technician use?
A) Right antecubital fossa
B) Left antecubital fossa
C) Right wrist
D) Left wrist
Answer: B
Rationale: Avoid the affected arm due to lymphedema risk from mastectomy (NHA Domain 3;
CLSI H3-A6). Left arm prevents infection spread and complies with safety standards.
2. What is the correct order of draw for venipuncture when collecting blood cultures, PT/PTT,
and a CBC?
A) CBC, PT/PTT, blood cultures
B) Blood cultures, PT/PTT, CBC
C) PT/PTT, blood cultures, CBC
D) CBC, blood cultures, PT/PTT
Answer: B
Rationale: Blood cultures first to avoid contamination; then citrate (PT/PTT), then EDTA (CBC)
(NHA Domain 3; CLSI H3-A5). Prevents additive carryover affecting coagulation tests.
3. A technician is performing a capillary puncture on an infant. Which lancet gauge is
appropriate?
A) 18G
B) 21G
C) 23G
D) 25G
Answer: D
Rationale: 25G lancet minimizes tissue trauma in infants (NHA Domain 4; CLSI H4-A5). Larger
gauges increase pain and hemolysis risk.
4. During venipuncture, the needle is inserted at what angle for the median cubital vein?
A) 5–10 degrees
,B) 15–30 degrees
C) 45–60 degrees
D) 90 degrees
Answer: B
Rationale: 15–30 degrees bevel-up ensures smooth entry and vein penetration without
through-and-through (NHA Domain 3; CLSI H3-A6). Steeper angles risk vein wall damage.
5. A patient has small, fragile veins. Which technique should the technician use to locate a vein?
A) Apply a cold compress
B) Use a warming pad for 5 minutes
C) Tighten the tourniquet for 2 minutes
D) Slap the arm vigorously
Answer: B
Rationale: Warming dilates veins for better visibility (NHA Domain 2; CLSI H3-A6). Cold
constricts; prolonged tourniquet risks hemoconcentration.
6. For a blood alcohol test, the technician should collect from which site?
A) Fingerstick
B) Vein in antecubital fossa
C) Heel
D) Earlobe
Answer: B
Rationale: Venous sample avoids contamination from skin alcohol; use non-alcohol antiseptic
(NHA Domain 4; CAP guidelines). Capillary risks false positives.
7. The technician notices blood flashback in the hub but no flow into the tube. What is the most
likely cause?
A) Wrong tube additive
B) Vein valve or partial bevel occlusion
C) Tourniquet too loose
D) Patient dehydrated
Answer: B
Rationale: Valve obstructs flow; reposition needle slightly (NHA Domain 3; CLSI H3-A6).
Dehydration slows flow but flashback occurs.
8. Which tube is collected first in order of draw for chemistry, coagulation, and hematology
panels?
A) Red (serum)
B) Blue (citrate)
C) Lavender (EDTA)
D) Green (heparin)
Answer: B
, Rationale: Citrate first to prevent clotting interference; order prevents cross-contamination (NHA
Domain 3; CLSI H1-A5).
9. A patient is a difficult draw with scarred veins. Which alternative site is acceptable for routine
labs?
A) Femoral vein
B) Hand vein
C) Jugular vein
D) Foot vein
Answer: B
Rationale: Dorsal hand veins for limited routine tests; avoid lower extremities for infection risk
(NHA Domain 3; CLSI H3-A6).
10. For a timed specimen (e.g., glucose tolerance), the technician notes the draw is 5 minutes
late. What action?
A) Discard and redraw
B) Note time on label and proceed
C) Use a different site
D) Skip the test
Answer: B
Rationale: Document discrepancy; labs may accept with notation if within tolerance (NHA
Domain 5; CAP Q-Probe).
11. The butterfly needle is used for which scenario?
A) Routine arm draw
B) Fragile veins or hard-to-reach sites
C) Arterial blood gas
D) Capillary collection
Answer: B
Rationale: Winged needle stabilizes for difficult access; 21–25G (NHA Domain 3; CLSI H3-A6).
Increases hemolysis risk if misused.
12. After venipuncture, apply pressure for how long to prevent hematoma?
A) 10 seconds
B) 30 seconds
C) 1 minute
D) Until bleeding stops
Answer: D
Rationale: Firm pressure until hemostasis; minimum 2 minutes for anticoagulated patients (NHA
Domain 3; CLSI H3-A6).