Free NCMA Phlebotomy Procedures and Order of Draw Questions and Answers

Question 1

A medical assistant is drawing blood for a CBC, a PT/INR, and a basic metabolic panel (BMP). What is the correct order of draw for these tests?

Accepted Answer

Light Blue, Red, Lavender

Answer

The correct order of draw is based on the additives in the tubes to prevent cross-contamination. The light blue top (sodium citrate) for coagulation studies like PT/INR is drawn first after blood cultures. This is followed by the serum tube (red or gold top) for the BMP, and finally the lavender top (EDTA) for the CBC.

Question 2

Which additive is found in a lavender-topped evacuated tube?

Accepted Answer

EDTA

Answer

Lavender-topped tubes contain the anticoagulant Ethylenediaminetetraacetic acid (EDTA). EDTA works by binding calcium, which is essential for the clotting cascade, thus preventing the blood from clotting. These tubes are primarily used for hematology tests like a complete blood count (CBC).

Question 3

During a venipuncture, the area around the puncture site begins to swell and fill with blood. This is known as a:

Accepted Answer

Hematoma

Answer

A hematoma is a collection of blood outside of a blood vessel, which occurs when the needle has gone through the vein or is only partially in the vein, causing blood to leak into the surrounding tissue. If this occurs, the tourniquet should be released and the needle withdrawn immediately, with pressure applied to the site.

Question 4

Which of the following sites should a medical assistant avoid for venipuncture?

Accepted Answer

An arm on the same side as a mastectomy

Answer

A medical assistant should avoid drawing blood from an arm on the same side as a previous mastectomy. The removal of lymph nodes during a mastectomy can impair lymphatic drainage, increasing the risk of infection and lymphedema if a venipuncture is performed on that arm. The other options are generally acceptable sites.

Question 5

What is the recommended angle of needle insertion for a routine venipuncture in the antecubital fossa?

Accepted Answer

15 to 30 degrees

Answer

The standard angle for needle insertion during a routine venipuncture is between 15 and 30 degrees. This angle allows the needle to enter the skin and then the vein without going through the vein or being too shallow. A steeper angle risks puncturing the back wall of the vein, while a shallower angle may not enter the vein properly.

NCMA - National Certified Medical Assistant Practice Test

NCMA - National Certified Medical Assistant Practice Test

Free NCMA Phlebotomy Procedures and Order of Draw Questions and Answers