RMA Venipuncture and Phlebotomy 3

Question 1

Which gauge needle is most commonly used for routine adult venipuncture?

Accepted Answer

21 gauge

Answer

A 21-gauge needle is the standard choice, balancing adequate flow with patient comfort.

Question 2

What complication results from drawing blood too quickly or with too small a needle, damaging red cells?

Accepted Answer

Hemolysis

Answer

Hemolysis is the rupture of red blood cells, which can falsely elevate potassium and other analytes.

Question 3

A bruise that forms at the puncture site due to blood leaking into surrounding tissue is called a:

Accepted Answer

Hematoma

Answer

A hematoma forms when blood escapes the vein into nearby tissue, often from a needle passing through the vein.

Question 4

Which tube additive is the anticoagulant of choice for coagulation studies such as PT and PTT?

Accepted Answer

Sodium citrate

Answer

Sodium citrate in the light blue top tube is used for coagulation testing because it reversibly binds calcium.

Question 5

What is the correct blood-to-additive ratio that must be maintained in a sodium citrate tube?

Accepted Answer

9 parts blood to 1 part additive

Answer

Coagulation tubes require a 9:1 blood-to-citrate ratio for accurate results, so they must be filled completely.

RMA Practice Test