Phlebotomy Fundamentals Flashcards
6 cards from real Certified Phlebotomy Technician Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Phlebotomy Fundamentals flashcards as text
A phlebotomist is performing a capillary puncture on a healthy adult's finger to collect specimens for a blood smear, a CBC, and a serum chemistry test. What is the correct order for collecting these specimens?
Answer: Blood smear, EDTA tube, serum tube
For capillary collections, the order of draw is different from venipuncture to minimize the effects of clotting. Blood smears are made first from the fresh drop of blood. Next, EDTA tubes (for CBC) are collected to prevent platelet clumping. Lastly, serum tubes are collected, as they are intended to clot.
During a venipuncture, the phlebotomist notices a hematoma forming at the site. Which of the following is the most appropriate immediate action?
Answer: Release the tourniquet, withdraw the needle, and apply firm pressure.
If a hematoma begins to form, it indicates that blood is leaking into the tissue surrounding the vein. The correct procedure is to immediately stop the blood draw by releasing the tourniquet, removing the needle, and applying firm, direct pressure to the site to minimize the size of the hematoma and prevent further injury.
A gray-topped tube is selected for blood collection. What is the primary function of the sodium fluoride additive in this tube?
Answer: To preserve glucose in the sample.
Gray-topped tubes contain sodium fluoride, which is an antiglycolytic agent that inhibits the breakdown of glucose (glycolysis) within the blood sample. They also contain potassium oxalate, an anticoagulant. This combination ensures an accurate glucose measurement, especially if testing is delayed.
A patient experiences a sharp, radiating pain down their arm as the needle is inserted. This is a potential sign of:
Answer: Nerve contact.
A sharp, electric, or radiating pain is a classic sign that the needle has come into contact with a nerve. If this occurs, the phlebotomist should immediately withdraw the needle and terminate the venipuncture to prevent potential nerve damage.
When processing a blood sample in a serum separator tube (SST), which step is critical for proper specimen quality?
Answer: Allowing the tube to clot fully before centrifugation.
For a serum separator tube (SST), the blood must be allowed to clot completely before being placed in a centrifuge. This usually takes about 30 minutes at room temperature. Centrifuging too early can result in a fibrin-rich serum or incomplete separation, compromising the specimen's integrity.
Which of the following situations would require a phlebotomist to draw a 'discard' tube before collecting a specimen for a coagulation test in a light blue top tube?
Answer: When using a winged infusion set (butterfly needle).
When using a winged infusion set, the air in the tubing will displace blood, leading to an underfilled tube. For coagulation tests (light blue top), the 9:1 blood-to-anticoagulant ratio is critical. Drawing a discard tube first purges the air from the tubing, ensuring the light blue top tube fills to the correct volume.