Author Question: A patient who is not on heparin and has no history of a factor deficiency has a prolonged partial ... (Read 69 times)

mmm · **on:** Jun 25, 2018

A patient who is not on heparin and has no history of a factor deficiency has a prolonged partial thromboplastin time (PTT). Select the test that should be performed next.

a. High-sensitivity C-reactive protein
b. Mixing studies for lupus anticoagulant
c. Thrombin time (TT)
d. Lipid panel

Question 2

A thrombosis risk testing profile is ordered on a patient being treated with warfarin for a blood clot in the leg. Select the best course of action.

a. Run the tests immediately.
b. Reject the order.
c. Perform only the tests for protein C and protein S.
d. Recommend the testing be postponed until the warfarin is discontinued.

yuyiding · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: B
The lupus anticoagulant results in a prolonged PTT. It is characterized by lack of correction when the patient plasma is mixed 1:1 with normal platelet poor plasma and the PTT repeated. None of the other listed findings prolong the PTT.

Answer to Question 2

ANS: D
Testing should be postponed until the warfarin has been discontinued for 10 to 14 days. Warfarin blocks the normal synthesis of vitamin Kdependent proteins, which include protein C and protein S.