Author Question: A coagulation screen is ordered on a patient who is a difficult draw. A 5-mL blue top tube is drawn ... (Read 82 times)

809779 · **on:** Jun 25, 2018

A coagulation screen is ordered on a patient who is a difficult draw. A 5-mL blue top tube is drawn but fills only halfway. What would be the appropriate next step?

a. Draw another half-filled 5-mL blue top tube, and combine the two tubes.
b. Discard the first tube, and attempt to draw a filled 5-mL blue top tube.
c. Draw a red top tube, and add blood to completely fill the blue top tube.
d. Send the half-filled blue top tube to the coagulation laboratory.

Question 2

Hepatitis B virus can survive on a dried surface at room temperature for:

a. 1 Day
b. 2 Days
c. 1 Week
d. 1 Month

kthug · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: B
The ratio of anticoagulant to blood is critical for valid coagulation testing; thus the blue top tube must be filled. Combining two half-filled blue top tubes will result in twice as much anticoagulant. Sending the half-filled tube to the laboratory also results in too much anticoagulant for the volume of blood; thus both of these will invalidate coagulation tests, prolonging results. As soon as blood is drawn into a red top tube, it begins to clot and this will result in an activated specimen when it is added to the blue top tube, also invalidating results.

Answer to Question 2

ANS: C
The hepatitis B virus can survive on a dried surface at room temperature for up to 1 week.