Page 26 - ractice Exam Questions and rationales

The physician orders a PT/PTT. Which of the following evacuated tubes should the medical
assistant select for collecting the specimen

A. light green

B. red

C. grey

D. light blue

Your response:
light blue
Correct response:
light blue
Rationale: A light blue top on the tube means that the tube contains buffered sodium citrate, an
additive that removes calcium to prevent blood from clotting. Therefore, this tube would be the
one used for the PT/PTT test since those tests are done to see how well the blood clots. The light
green tubes are used for STAT tests and will counteract the clotting tubes. Red tubes are for tests
on hormones, and gray tubes are typically used for glucose testing and for testing blood alcohol
content.
An adult patient presents with fever, muscular pain, and congestion. Which of the following is
the appropriate response for the medical assistant following the physician's orders?