A patient has been prescribed rivaroxaban (Xarelto) for deep vein thrombosis (DVT). Which statement by the patient indicates understanding of medication teaching?

Activated partial thromboplastin time (aPTT).

Dabigatran (Pradaxa) is a direct oral anticoagulant (DOAC) that inhibits thrombin, a key enzyme in the coagulation cascade.

Dabigatran prolongs the aPTT, which is a measure of the intrinsic and common pathways of coagulation.The aPTT can be used to monitor the anticoagulant effect of dabigatran, although routine monitoring is not required.

Choice A) Prothrombin time (PT) is wrong because PT measures the extrinsic and common pathways of coagulation, which are not affected by dabigatran.

PT is used to monitor warfarin therapy, not dabigatran.

Choice B) International normalized ratio (INR) is wrong because INR is a standardized version of PT that is used to monitor warfarin therapy, not dabigatran.

INR is not affected by dabigatran.

Choice D) Platelet count is wrong because platelet count is a measure of the number of platelets in the blood, which are involved in primary hemostasis.

Platelet count is not affected by dabigatran, which acts on secondary hemostasis.

Normal ranges for these tests are:

• aPTT: 25 to 35 seconds

• PT: 11 to 13.5 seconds

• INR: 0.8 to 1.2

• Platelet count: 150,000 to 450,000 per microliter of blood

Heparin is an anticoagulant that inhibits blood clotting and prevents harmful clots from forming in blood vessels.However, heparin can also cause some serious side effects, such as bleeding, bruising, low platelet count, allergic reactions, and osteoporosis.

Therefore, patients who are at a high risk for developing these adverse effects should be monitored closely and have their heparin dose adjusted accordingly.

Choice A is correct because a patient who is post-op day 1 from brain surgery has a high risk of bleeding from the surgical site or intracranially.Heparin can increase this risk and cause life-threatening hemorrhage.

Therefore, this patient should not receive heparin unless absolutely necessary and under strict supervision.

Choice B is wrong because a patient with a pulmonary embolism (PE) is a candidate for heparin therapy.

A PE is a blood clot that blocks the blood flow to the lungs and can cause respiratory failure and death.Heparin can prevent the clot from becoming larger and causing more damage, and also prevent new clots from forming.

Therefore, this patient would benefit from heparin therapy and is not at a high risk of adverse effects.

Choice C is correct because a patient with active peptic ulcer disease (PUD) has a high risk of bleeding from the stomach or duodenum.

PUD is a condition where the lining of the digestive tract is eroded by stomach acid and bacteria.Heparin can worsen this condition and cause ulcer bleeding or perforation.

Therefore, this patient should avoid heparin therapy unless absolutely necessary and under strict supervision.

Choice D is wrong because a patient with uncontrolled atrial fibrillation (AF) is a candidate for heparin therapy.

AF is an irregular heartbeat that can cause blood clots to form in the heart chambers and travel to other organs, such as the brain or lungs.Heparin can prevent these clots from forming and reduce the risk of stroke or PE.

Therefore, this patient would benefit from heparin therapy and is not at a high risk of adverse effects.

Normal ranges of heparin depend on the type of heparin used (unfractionated heparin or low molecular weight heparin), the method of administration (intravenous or subcutaneous), and the indication for use (prophylaxis or treatment).Generally, the therapeutic range for heparin level is 0.3 - 0.7 U/mL, measured by anti-Xa assay.However, this range may vary depending on the pregnancy stage and the type of heparin used.The dose of heparin should be individualized according to the results of suitable laboratory tests and clinical response.