A 33-year-old man with severe bacterial meningitis is intubated and unresponsive in the Intensive Care...

Comprehensive and Detailed Explanation:

An advance directive is a legally binding document that outlines a competent person ' s preferences regarding future medical care. If the patient clearly stated a refusal of treatment in the event of a life-threatening condition, this directive must be followed, even if the patient is currently incapacitated and family disagrees.

Toronto Notes 2023 – Ethics and Law:

“Advance directives must be respected when valid, clear, and applicable. Substitute decision-makers cannot override them.”

MCCQE1 Objectives (ELOM > 90-4: Informed Consent and Advance Directives):

“Candidates must apply valid advance directives to guide care for incapacitated patients.”

B (parents as SDMs) is incorrect if an advance directive exists. A and D are irrelevant—capacity has already been documented. C is unnecessary when an advance directive is clear.

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