A nurse is evaluating a client who has heart failure and is receiving warfarin. Which of the following statements by the client indicates a need for further teaching?

Mannitol is an osmotic diuretic that increases urine output and decreases intracranial pressure and intraocular pressure. The nurse should check the urine output before giving the medication to ensure adequate renal function and prevent fluid overload and electrolyte imbalance. The normal urine output is 0.5 to 1 mL/kg/hr.

Choice B is wrong because checking the blood pressure is not specific to mannitol administration. Mannitol can cause hypotension or hypertension depending on the fluid status of the client, but this is not the priority action before giving the medication.

Choice C is wrong because checking the blood glucose is not relevant to mannitol administration. Mannitol does not affect blood glucose levels.

Choice D is wrong because checking the oxygen saturation is not related to mannitol administration. Mannitol does not affect oxygen saturation levels.

Warfarin is an anticoagulant that prevents blood clots from forming or growing larger. It works by inhibiting the synthesis of vitamin K-dependent clotting factors in the liver. The INR (international normalized ratio) is a measure of how long it takes the blood to clot.The therapeutic range for INR depends on the indication for warfarin therapy, but for atrial fibrillation, it is usually between 2 and 3. An INR level of 3.5 is above the therapeutic range, which means the blood is too thin and the patient is at risk of bleeding. The nurse should hold the warfarin dose and notify the physician, who may order vitamin K to reverse the effects of warfarin.

Choice A) Administer vitamin K as ordered by physician is wrong because vitamin K is not indicated unless the physician orders it based on the patient’s condition and INR level.

Vitamin K is an antidote for warfarin overdose and can reverse its anticoagulant effects.

However, administering vitamin K without a physician’s order may cause the INR to drop below the therapeutic range and increase the risk of clotting.

Choice B) Administer heparin as ordered by physician is wrong because heparin is another anticoagulant that works by activating antithrombin, a natural inhibitor of clotting factors.

Heparin is used for acute treatment of thromboembolic disorders, such as deep vein thrombosis or pulmonary embolism.

It is not indicated for atrial fibrillation unless there is evidence of acute thrombosis.

Administering heparin to a patient with an elevated INR would increase the risk of bleeding.

Choice C) Administer warfarin as ordered by physician is wrong because warfarin is the cause of the elevated INR and should be withheld until the INR returns to the therapeutic range.

Continuing to administer warfarin would further increase the INR and the risk of bleeding.