Correct Answer: D

Rationale: The correct answer is D. Spironolactone is a potassium-sparing diuretic, so patients should choose low-potassium foods. Apple juice is a better choice than orange juice in this case as it is lower in potassium. Option A is incorrect because increasing fluid intake excessively is not necessary. Option B is incorrect as salt substitutes are high in potassium, which should be avoided. Option C is incorrect because patients on spironolactone should avoid increasing their potassium intake.

Correct Answer: D

Rationale: The correct answer is D, Hypokalemia. Generalized weakness, muscle weakness, leg cramps, and cardiac dysrhythmias are manifestations of hypokalemia. Checking the potassium level is essential in this case. Hypocalcemia typically presents with facial muscle spasms, not the symptoms mentioned. Hypermagnesemia does not typically cause the symptoms described. It's important to note that orange juice is high in potassium and would be advisable to drink if the patient was hypokalemic. Loose stools are more commonly associated with hyperkalemia, not hypokalemia.

Correct Answer: B

Rationale: The correct answer is B. A serum calcium level of 18 mg/dL is significantly elevated, posing a high risk for cardiac dysrhythmias. Immediate action is required to initiate cardiac monitoring and notify the healthcare provider. While the abnormalities in arterial blood pH, serum potassium, and arterial oxygen saturation also need attention, they are not as immediately life-threatening as the critically high serum calcium level. Therefore, addressing the serum calcium level takes precedence in this scenario.

Correct Answer: A

Rationale: The correct answer is A. An alert, older patient can self-assess for signs of dehydration like dry mouth. This instruction is appropriate as it encourages the patient to respond to early signs of dehydration. Choice B is incorrect because the thirst mechanism decreases with age and feeling thirsty may not accurately indicate the need for fluids. Choice C is incorrect as many older patients prefer to limit evening fluid intake to enhance sleep quality. Choice D is incorrect because an older adult who is lethargic or confused may not be able to accurately assess their need for fluids.

Correct Answer: D

Rationale: The patient's pH of 7.48 indicates alkalosis, and the low PaCO2 of 32 mm Hg suggests a respiratory cause. The HCO3 level is normal, ruling out metabolic causes. Therefore, the correct interpretation is respiratory alkalosis. Options A, B, and C are incorrect as they do not align with the pH and PaCO2 values provided.