Correct Answer: B

Rationale: The correct answer is B: 5 mL.
To calculate the mL needed for a 5 mg dose of metoprolol, divide the desired dose (5 mg) by the concentration of the medication (1 mg/mL). 5 mg / 1 mg/mL = 5 mL. This ensures the nurse administers the correct dose.

Choices A, C, and D are incorrect because they do not accurately calculate the mL needed for a 5 mg dose of metoprolol.

Correct Answer: A

Rationale: The correct answer is A: Enoxaparin. Following hip arthroplasty, the client is at risk for deep vein thrombosis (DVT) due to immobility. Enoxaparin is a low molecular weight heparin that helps prevent DVT by inhibiting clot formation. It is commonly prescribed postoperatively for thromboprophylaxis. Clopidogrel (
B) is an antiplatelet medication used for cardiovascular conditions, not typically for DVT prevention post-hip arthroplasty. Alteplase (
C) is a thrombolytic agent used to dissolve blood clots in emergency situations like stroke or pulmonary embolism, not for prophylaxis. Aspirin (
D) is an antiplatelet medication that may be used for cardiovascular prophylaxis but is less effective for preventing DVT compared to enoxaparin.

Correct Answer: D

Rationale: The correct answer is D: Check the client's vital signs. This is the first action the nurse should take to assess the client's condition. Vital signs can provide crucial information about the client's current status, especially in a client with congestive heart failure taking digoxin. Nausea and weakness could be signs of digoxin toxicity, which can manifest as gastrointestinal symptoms and changes in vital signs. By checking the vital signs, the nurse can identify any abnormalities and promptly intervene if necessary. Requesting a dietitian consult (
A) is not the priority as the client's immediate symptoms need to be addressed first. Requesting an antiemetic (
B) may provide symptomatic relief but does not address the underlying cause. Suggesting rest before eating (
C) is not the priority without assessing the client's vital signs first.

Correct Answer: D

Rationale: The correct answer is D: Isosorbide. Isosorbide is a nitrate medication used to treat angina by dilating blood vessels, which can lead to a severe drop in blood pressure when combined with sildenafil, a medication for erectile dysfunction that also causes vasodilation. This combination can result in a dangerous decrease in blood pressure, potentially leading to fainting or even a heart attack. Phenytoin, prednisone, and metronidazole do not have significant interactions with sildenafil.

Correct Answer: A

Rationale: The correct answer is A: 0.25 mL.
To calculate the mL of lidocaine to administer, use the formula: Desired dose (50 mg) / Stock concentration (200 mg/mL) = Volume to administer (X mL). Substituting the values, 50 mg / 200 mg/mL = X. Solving for X, we get X = 0.25 mL. This calculation ensures precise dosing accuracy.

Choices B, C, and D are incorrect as they do not align with the calculated result. It's crucial to follow the formula to prevent medication errors.