Before administering a nonselective adrenergic blocker, what should the nurse assess?

Correct Answer: A

Rationale: Monitor vital signs and assess cardiovascular status including pulse, blood pressure, and cardiac output to evaluate for possible cardiac effects. Although assessment of bowel sounds, appetite, serum albumin level, or serum sodium and potassium levels may be important to patient care, they are not related to administration of a nonselective adrenergic blocking agent. The nurse should prioritize cardiovascular assessments to ensure patient safety.

Correct Answer: C

Rationale: Drug B, as an inducer of the cytochrome p-450 system, increases the metabolism of Drug A, leading to lower plasma concentrations and reduced therapeutic effects of Drug A. This interaction is a common concern in polypharmacy, where one drug affects the metabolism of another. Monitoring for decreased efficacy of Drug A is essential to ensure the patient receives adequate treatment. Increased adverse effects of Drug B or decreased effects of Drug B are less likely in this scenario.

Correct Answer: B

Rationale: Naloxone (Narcan) is the antidote for opioid-induced respiratory depression and should be readily available when administering opioid analgesics during labor. It works by reversing the effects of opioids on the respiratory system, restoring normal breathing. Oxycodone, meperidine, and morphine are opioids and would exacerbate respiratory depression. Therefore, naloxone is the correct medication to have on hand.

Correct Answer: D

Rationale: Weight loss, tachycardia, and goitre suggest hyperthyroidism (e.g., Graves'). Verapamil controls rate but not thyroid function. Radioactive iodine (131I) treats long-term, not immediately. Carbamazepine is for seizures, L-thyroxine worsens hyperthyroidism. Atenolol, a beta-blocker, immediately reduces tachycardia and symptoms by blocking adrenergic effects, suitable for acute management while awaiting antithyroid drugs (e.g., propylthiouracil). Its symptomatic relief is critical in hyperthyroid crises.

Correct Answer: C

Rationale: Higher potency (lower dose for effect) can coexist with lower efficacy (max effect), true, as potency reflects affinity, not ceiling effect. Higher receptor affinity increases potency, true, per receptor theory. Lower potency doesn't mandate lower efficacy; a less potent drug can achieve the same max effect with more dose, making this false. Higher potency with equal efficacy is true (e.g., partial agonists). This pharmacodynamic distinction is vital for drug selection, where efficacy often trumps potency.