A 72 yo male presents with obtundation, a 3 cm mass in his right upper lobe of his lung, dehydration, and a calcium of 16.4 mg/dl. The most likely cause of his hypercalcemia is:

Correct Answer: B

Rationale: Elevated PTHrP is the most likely cause of hypercalcemia in this patient with lung cancer, as it is commonly secreted by malignancies like squamous cell carcinoma.

Correct Answer: C

Rationale: Digitalis slows the heart rate through parasympathetic system activation and promotes sodium and water excretion through improved cardiac output to the kidney. Depletion of serum potassium (hypokalemia) may potentiate digitalis toxicity. Sodium and water excretion is activated through the parasympathetic system due to improved cardiac output to the kidneys. Albumin level is not affected by digitalis. Digitalis allows more calcium to remain in the cell through a slowing of the sodium-dependent calcium pump.

Correct Answer: A

Rationale: Left-sided diastolic dysfunction involves impaired ventricular filling with a preserved ejection fraction (typically normal, >50%), making 'True' (A) correct. The generated choices C and D are incorrect based on medical knowledge.

Correct Answer: C

Rationale: The angiotensin-converting enzyme(ACE) inhibitors frequently cause orthostatic hypotension, and patients should be taught to change position slowly to allow the vascular system time to compensate for the position change. Increasing fluid intake may counteract the effect of the medication, and the patient is taught to use gum or hard candy to relieve dry mouth. The BP should be taken in the nondominant arm by newly diagnosed patients in the morning, before taking the medication, and in the evening. Because ACE inhibitors cause potassium retention, increased intake of high-potassium foods is inappropriate.

Correct Answer: B

Rationale: The myocardium is the thick middle layer of cardiac muscle responsible for the heart's pumping action.