Phlebotomy Test Blood Collection Equipment and Supplies 1

Question 1

What is the standard needle gauge most commonly used for routine adult venipuncture?

Accepted Answer

21 gauge

Answer

The 21-gauge needle is the standard for routine adult venipuncture, providing adequate blood flow without causing excessive hemolysis.

Question 2

Which evacuated tube color contains EDTA as its anticoagulant and is most commonly used for CBC testing?

Accepted Answer

Lavender/purple

Answer

Lavender/purple top tubes contain EDTA, which chelates calcium to prevent clotting and is the additive of choice for hematology tests like CBCs.

Question 3

What is the primary purpose of applying a tourniquet during venipuncture?

Accepted Answer

To distend veins by restricting venous blood flow

Answer

A tourniquet restricts venous return, causing veins to distend and become more visible and palpable for easier needle access.

Question 4

What is the maximum recommended time a tourniquet should remain applied during venipuncture?

Accepted Answer

1 minute

Answer

A tourniquet should not remain applied for more than 1 minute because prolonged application causes hemoconcentration, which can falsely elevate cell counts and large-molecule analytes.

Question 5

Which antiseptic is most commonly used to cleanse the venipuncture site for routine blood collection?

Accepted Answer

70% isopropyl alcohol

Answer

70% isopropyl alcohol is the standard antiseptic for routine venipuncture; it must be allowed to air dry completely before needle insertion to prevent hemolysis and inaccurate results.

Phlebotomy Practice Test

Phlebotomy Practice Test

Phlebotomy Test Blood Collection Equipment and Supplies 1