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Cerebral Blood Flow Percentage — FRCA Primary MCQ

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ModeratePhysiology - CardiovascularCerebral Blood Flow PercentageFRCA Primary

What percentage of cardiac output does the brain normally receive?

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Correct answer: D — 15%

The brain receives approximately 15% of cardiac output (approximately 750 mL/min or 50 mL/100g/min). The brain has a high metabolic rate (approximately 20% of total body oxygen consumption despite being only ~2% of body weight) and almost no oxygen stores, making it highly vulnerable to ischaemia.

Reference: Power Kam 2018 Principles of Physiology for the Anaesthetist