ASCP Orders and Equipment Selection 3

Question 1

Which tube additive is an antiglycolytic agent that preserves glucose levels in blood specimens?

Accepted Answer

Sodium fluoride

Answer

Sodium fluoride is an antiglycolytic agent found in gray-topped tubes that inhibits the enzyme enolase, preventing glycolysis and preserving glucose concentrations.

Question 2

What is the primary purpose of a tourniquet during venipuncture?

Accepted Answer

To enlarge veins by restricting venous blood flow

Answer

A tourniquet restricts venous return while allowing arterial flow to continue, causing veins to distend and become more visible and palpable for venipuncture.

Question 3

A blood collection tube has lost its vacuum. What is the correct action?

Accepted Answer

Discard the tube and use a new one

Answer

Tubes that have lost their vacuum cannot be repaired. The correct action is to discard the defective tube and use a new, properly sealed tube.

Question 4

Which tube should be drawn immediately after the blood culture bottles in the standard order of draw?

Accepted Answer

Light blue-topped tube

Answer

The order of draw places light blue (sodium citrate) tubes immediately after blood culture bottles to prevent additive contamination of coagulation tests.

Question 5

Which of the following is the correct angle for inserting a needle during routine venipuncture?

Accepted Answer

15 to 30 degrees

Answer

A 15 to 30 degree angle is recommended for routine venipuncture to properly enter the vein without going through it or causing damage to surrounding tissue.

ASCP Phlebotomy Technician Exam Practice Test

ASCP Phlebotomy Technician Exam Practice Test

ASCP Orders and Equipment Selection 3