Prothrombin Time Quiz

A phlebotomist is performing a prothrombin time test to monitor a patient's oral anticoagulant therapy.

• True

• False

In a phlebotomy procedure, if you have to maintain the ratio of anticoagulant to blood as one part anticoagulant to five parts blood (1:5), would you agree?

• True

• False

The phlebotomist can use the results from the prothrombin time to adjust the patient’s anticoagulant dose during a blood draw.

• True

• False

In a real-life scenario, the simplicity of the phlebotomy procedure makes it unnecessary to run controls.

• True

• False

A phlebotomist is performing a PT test on a patient. Which of the following statements is NOT true about this test?

• It monitors oral anticoagulant therapy

• It measures the intrinsic pathway

• It is a coagulation screening test

• Its reference value is 11–13 seconds

A phlebotomist is preparing to draw blood for a prothrombin time test. Which of the following statements is true about this procedure?

• The anticoagulant-to-blood ratio is 9:1.

• The blood sample is collected in sodium oxalate.

• The anticoagulant-to-blood ratio is 1:5.

• The anticoagulant is 3.2% sodium citrate.

In a phlebotomy setting, the PT ratio:

• is calculated by dividing the patient's clotting time in seconds by the average clotting time in seconds of a healthy individual

• compares the patient’s clotting time with his previous clotting times

• compares patient's clotting time with a normal control

• is found by dividing the patient's clotting time by the International Sensitivity Index (ISI)

A phlebotomist is preparing to draw blood for a prothrombin time test. Which of the following conditions in the patient will not affect the results of the test?

• factor II deficiency

• factor VIII deficiency

• severe vitamin K deficiency

• liver disease

A phlebotomist is preparing to perform a prothrombin time test. Which of the following samples should they avoid using?

• plasma

• citrated whole blood

• serum

• capillary puncture blood

A phlebotomist is preparing to draw blood for a prothrombin time test. Which of the following factors is NOT measured by this test?

• V

• VII

• IX

• X