Diagnostic Methods
Diagnostic Methods ( 5 Questions)
A nurse is administering heparin to a client who has a deep vein thrombosis.
The nurse should monitor which of the following laboratory values to evaluate the effectiveness of the therapy?
Prothrombin time (PT) is another test that measures how long it takes for blood to clot, but it is used to monitor the effectiveness of warfarin therapy, which is another anticoagulant that affects a different set of clotting factors than heparin.
International normalized ratio (INR) is a standardized way of reporting the PT results, which are affected by warfarin therapy, not heparin therapy.
Activated partial thromboplastin time (aPTT) is a test that measures how long it takes for blood to clot. It is used to monitor the effectiveness of heparin therapy, which is an anticoagulant (blood thinner) that prevents the formation of blood clots. Heparin affects one set of clotting factors that are measured by the aPTT test. The normal range of aPTT is 30-40 seconds, but in patients receiving heparin therapy, the range is 1.5-2.5 times the control value in seconds.
Platelet count is a test that measures the number of platelets in the blood, which are cells that help with clotting. Platelet count is not affected by heparin therapy and does not reflect its effectiveness.
Activated partial thromboplastin time (aPTT) is a test that measures how long it takes for blood to clot. It is used to monitor the effectiveness of heparin therapy, which is an anticoagulant (blood thinner) that prevents the formation of blood clots. Heparin affects one set of clotting factors that are measured by the aPTT test. The normal range of aPTT is 30-40 seconds, but in patients receiving heparin therapy, the range is 1.5-2.5 times the control value in seconds.
Choice A is wrong because prothrombin time (PT) is another test that measures how long it takes for blood to clot, but it is used to monitor the effectiveness of warfarin therapy, which is another anticoagulant that affects a different set of clotting factors than heparin.
Choice B is wrong because international normalized ratio (INR) is a standardized way of reporting the PT results, which are affected by warfarin therapy, not heparin therapy.
Choice D is wrong because platelet count is a test that measures the number of platelets in the blood, which are cells that help with clotting. Platelet count is not affected by heparin therapy and does not reflect its effectiveness.