Regarding inhaled anaesthetics:

Correct Answer: C

Rationale: Nitrous oxide has a high minimum alveolar concentration (MAC >100%), not low, due to low potency, so that's false. Halogenated agents (e.g., isoflurane) have higher brain:blood coefficients, reflecting solubility, making that false. They reduce mean arterial pressure (MAP) proportional to alveolar concentration via vasodilation, a true statement. Nitrous oxide does decrease tidal volume and increase respiratory rate, true. They don't reduce cerebral metabolic rate via blood flow alone but directly. MAP reduction is a key hemodynamic effect, guiding anesthetic depth monitoring.

Correct Answer: B

Rationale: Converting atrial fibrillation (AF) to sinus rhythm requires cardioversion or antiarrhythmics. Digoxin controls rate, not rhythm, ineffective for conversion. Atenolol, a beta-blocker, and diltiazem, a calcium channel blocker, manage rate, not rhythm restoration. Lidocaine treats ventricular arrhythmias. Amiodarone, a class III antiarrhythmic, prolongs repolarization, effectively converting AF to sinus rhythm, especially in acute settings, outperforming others. Its broad-spectrum action is key in AF management, balancing efficacy and safety.

Correct Answer: B

Rationale: Buspirone, an anxiolytic, requires 2-4 weeks for effect and is dosed thrice daily , showing understanding. Immediate relief is false'it's not a benzo. Alcohol worsens anxiety. It's non-sedating . Thrice-daily dosing aligns with buspirone's steady-state need, key in anxiety where consistency matters, making B the correct statement.

Correct Answer: D

Rationale: Mean effective dose (ED50) affects 50% of a population, but individuals vary-some need more or less due to metabolism, weight, or genetics, a clinical reality. Severe side effects aren't 50%-that's toxicity. Ethnic differences influence response, but dose variation is broader. No effect in 50% misreads ED50. Dose adjustment reflects individual pharmacokinetics, key to practice.

Correct Answer: B

Rationale: The most common side effect of insulin therapy is hypoglycemia, which occurs when the blood sugar levels drop too low. Insulin helps lower blood sugar levels by promoting the uptake of glucose into cells, but an excessive dose of insulin or changes in diet and physical activity can lead to hypoglycemia. Symptoms of hypoglycemia may include shakiness, sweating, dizziness, confusion, and hunger. It is important for individuals using insulin to be aware of the signs and symptoms of hypoglycemia and be prepared to treat it promptly with fast-acting glucose sources. Regular monitoring of blood sugar levels can help prevent and manage episodes of hypoglycemia.