Phlebotomy — practice questions

8% of the exam ≈12 real questions 12 free questions here

12 scored items, and the most rule-driven domain on the exam. Site selection, order of draw, tube additives, and what causes a rejected or hemolyzed specimen. These are exact-recall points — learn them once and they are free.

Where people lose points

• Order of draw exists to prevent additive carryover, so it is tested as a sequence, not as isolated tubes. Blood cultures always come first.
• The median cubital vein is first choice. The basilic is last resort — it sits near the brachial artery and median nerve.
• The tourniquet comes off within one minute. Leaving it on causes hemoconcentration and skews results.
• Never draw from the arm on the side of a mastectomy, an active IV line, a hematoma, or a sclerosed vein.
• Hemolysis has identifiable causes — vigorous shaking, too small a needle, forceful syringe pull, alcohol not dry. Questions usually ask which action caused it.

Questions and answers, explained

All 6 questions above, with the correct answer and why it is correct. Everything here is on phlebotomy.

1. The requisition reads "fasting lipid panel." The patient tells the medical assistant they drank a sweetened coffee 45 minutes ago. What should the medical assistant do?

   • ACollect the specimen now and write the exact collection time on the label.
   • BHave the patient drink water, wait 30 minutes, and then collect the specimen.
   • CReport the intake to the provider and follow their direction about collecting now or rescheduling.Correct
   • DCancel the order and tell the patient to return the next morning fasting.

   Why: A fasting lipid panel requires 9 to 12 hours with nothing by mouth except water; caloric intake, especially sugar, raises triglycerides and invalidates the fasting result. The medical assistant documents and reports the deviation and lets the provider decide whether to draw a nonfasting specimen or reschedule. Canceling the order outright (D) is outside the medical assistant's scope of practice, and 30 minutes of water (B) does not restore the fasting state.

   Reference Domain 3E; k125 patient preparation; NCEP ATP III / NIH MedlinePlus fasting lipid panel requirement (9-12 hours)

2. A provider orders a blood alcohol level for legal purposes. Which skin antiseptic should the medical assistant use on the venipuncture site?

   • A70% isopropyl alcohol pad
   • BAlcohol-based hand rub applied to the site
   • CAqueous benzalkonium chloride or povidone-iodineCorrect
   • DChlorhexidine gluconate in 70% isopropyl alcohol

   Why: Alcohol-containing antiseptics can contaminate a legal blood alcohol specimen and falsely elevate the reported value, so a non-alcohol aqueous antiseptic such as benzalkonium chloride or povidone-iodine is used. Choice D is a common trap because chlorhexidine skin preps are typically formulated in alcohol. Legal specimens also require chain-of-custody documentation from collection through reporting.

   Reference Domain 3E; k127 chain of custody; k139 special collections; forensic blood alcohol collection standard (non-alcohol aqueous antiseptic)

3. At what angle and orientation should the needle enter the skin for a routine antecubital venipuncture?

   • A15 to 30 degrees with the bevel upCorrect
   • B15 to 30 degrees with the bevel down
   • C45 to 60 degrees with the bevel up
   • D90 degrees with the bevel down

   Why: CLSI directs that the needle enter at 30 degrees or less, and a 15 to 30 degree approach with the bevel up follows the path of a superficial antecubital vein and lets the bevel slice cleanly into the lumen. A steeper angle (C, D) pushes the needle through the back wall of the vein and into deeper structures, and a bevel-down entry tends to shear the vein wall and block flow against it.

   Reference Domain 3E; k133 insertion and removal techniques; CLSI venipuncture standard (PRE02, formerly GP41) needle angle 30 degrees or less

4. Midway through a venipuncture, a patient seated in a phlebotomy chair becomes pale and diaphoretic and says the room is spinning. What should the medical assistant do first?

   • ARemove the tourniquet and needle, lower the head, and support them from falling.Correct
   • BFinish the draw quickly, and then have the patient lie down flat on the exam table.
   • CLeave the patient seated and go get ammonia inhalants from the supply cabinet.
   • DGive the patient orange juice to bring their blood sugar back up.

   Why: These are presyncope symptoms, and the first action is always to discontinue the draw by removing the tourniquet and needle, then protect the patient from a fall by lowering the head or laying them flat and staying with them. Never leave a lightheaded patient alone (C); ammonia inhalants are no longer recommended because they can trigger bronchospasm and mask a serious cause. Giving anything by mouth (D) to a patient who may lose consciousness creates an aspiration risk.

   Reference Domain 3E; k126 patient comfort/anxiety; Domain 3B k81 syncope response

5. A medical assistant is performing a heel stick on a 2-week-old infant. Which practice is correct?

   • APuncture the posterior curvature (back) of the heel to a depth of 3 mm.
   • BPuncture the medial or lateral plantar surface of the heel no deeper than 2.0 mm.Correct
   • CPuncture the great toe to a depth of 2.0 mm.
   • DPuncture the center of the plantar arch to a depth of 1.0 mm.

   Why: CLSI limits infant heel puncture to the medial or lateral plantar surface of the heel at a depth no greater than 2.0 mm, which reaches the dermal capillary bed lying about 0.35 to 1.6 mm below the skin without striking the calcaneus. Puncturing the posterior curvature or going deeper than 2.0 mm (A) risks bone injury and osteomyelitis, and the arch and toes are not acceptable sites.

   Reference Domain 3E; CLSI GP42 capillary blood collection (heel puncture depth no greater than 2.0 mm, medial/lateral plantar surface)

6. A patient who takes warfarin daily has just finished a venipuncture in the antecubital fossa. What is the correct postprocedural care of the site?

   • AFold the patient's arm up at the elbow over the gauze until bleeding stops.
   • BHold firm pressure with the arm straight until the bleeding fully stops.Correct
   • CBandage over folded gauze right away and have the patient press on the wrap.
   • DPlace an ice pack over the gauze for several minutes to close the puncture.

   Why: Firm direct pressure with the arm extended is what seals the vein. Bending the elbow feels like pressure to the patient but does not compress the puncture reliably, and it is a classic cause of hematoma and bruising. Anticoagulants such as warfarin and apixaban, and antiplatelet drugs such as clopidogrel and daily aspirin, all prolong bleeding, so hold longer than the usual three to five minutes and confirm the site has stopped before bandaging. Bandaging a site that is still oozing hides continued bleeding under the dressing. Instruct the patient to leave the bandage on at least 15 minutes, longer on an anticoagulant, and to avoid heavy lifting with that arm. Ice is not standard care for a routine puncture site.

   Reference NHA CCMA Test Plan Domain 3E Phlebotomy (3E9 postprocedural care; k137 bandaging procedures); CLSI PRE02 (formerly GP41) Collection of Diagnostic Venous Blood Specimens, postprocedural care and bandaging

Topics inside this domain

• Order of draw and tube additives
• Injection routes, sites and angles
• Venipuncture vein selection and what to avoid
• Specimen labeling and patient identification

Drill other domains

• Foundational Knowledge and Basic Science (10%)
• Anatomy and Physiology (5.3%)
• Patient Intake and Vitals (9.3%)
• General Patient Care (18.7%)
• Infection Control and Safety (10%)
• Point of Care Testing and Laboratory Procedures (6%)

← Back to the full practice exam