NRCMA Phlebotomy 3

Question 1

Which tube should be drawn FIRST when collecting only a coagulation (PT/INR) specimen using a butterfly needle?

Accepted Answer

Draw a discard tube first, then fill the citrate tube

Answer

With a butterfly set, air in the tubing can underfill the first tube, so a discard tube ensures the citrate tube fills to the proper ratio.

Question 2

What is the minimum waiting time after a patient has had an IV removed before drawing blood from that site?

Accepted Answer

At least 2–5 minutes

Answer

Waiting at least 2–5 minutes allows residual IV fluid to clear and ensures specimen integrity.

Question 3

A phlebotomist notices the blood in the tube is hemolyzed. Which of the following is a common cause?

Accepted Answer

Mixing the tube too vigorously

Answer

Vigorous mixing or shaking of blood tubes causes mechanical destruction of red blood cells, resulting in hemolysis.

Question 4

Which of the following analytes would be MOST affected by a hemolyzed specimen?

Accepted Answer

Potassium

Answer

Potassium is highly concentrated inside red blood cells, so hemolysis falsely elevates serum potassium levels.

Question 5

When should a phlebotomist perform hand hygiene?

Accepted Answer

Before and after each patient contact

Answer

Standard precautions require hand hygiene both before and after patient contact to prevent cross-contamination.

(NRCMA) Nationally Registered Certified Medical Assistant Practice Test