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Mannitol for raised ICP — FRCA Primary MCQ

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EasyPharmacologyMannitol for raised ICPFRCA Primary

During craniotomy for traumatic brain injury, the anaesthetist chooses an osmotic agent to reduce acute brain swelling. Which drug is most appropriate?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: B — Mannitol

Mannitol increases plasma osmolality and draws water out of brain tissue when the blood-brain barrier is relatively intact. Nitrous oxide is less appropriate because it would fit a different clinical clue or a separate anaesthetic problem. Morphine is less appropriate because it would fit a different clinical clue or a separate anaesthetic problem. Ephedrine is less appropriate because it would fit a different clinical clue or a separate anaesthetic problem. Esmolol is less appropriate because it would fit a different clinical clue or a separate anaesthetic problem. In Primary FRCA pharmacology, link the clinical effect to the receptor, distribution or elimination mechanism rather than memorising isolated facts.

Reference: Peck, Hill & Williams Pharmacology for Anaesthesia and Intensive Care; BNF; Primary FRCA textbooks