Normal CPP — FRCA Primary MCQ

Instant feedback + full explanation. One question, done properly.

ModeratePhysiology - CardiovascularNormal CPPFRCA Primary

A healthy supine adult has a mean arterial pressure of 90 mmHg and an intracranial pressure fluctuating between 10 and 15 mmHg. Central venous pressure is lower than intracranial pressure. Approximately what is the cerebral perfusion pressure?

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

Reveal the answer and explanation

Correct answer: D — 75–80 mmHg

Explanation lettering: E = shown as A · D = shown as B · A = shown as C · C = shown as D · B = shown as E

The correct answer is C. Cerebral perfusion pressure is the pressure gradient driving cerebral blood flow. When intracranial pressure exceeds central venous pressure, CPP is calculated as MAP − ICP. Here, CPP ranges from 90 − 15 = 75 mmHg to 90 − 10 = 80 mmHg. This is consistent with the commonly quoted normal resting CPP range of approximately 60–80 mmHg. Option A may be confused with a traditional lower boundary of cerebral autoregulation, but it is not the calculated value. Option B effectively ignores or incorrectly handles ICP. Options D and E are incompatible with the supplied pressures; CPP cannot exceed MAP when ICP is positive.

Reference: Mount CA, Das JM. Cerebral Perfusion Pressure. StatPearls, 2026 edition; updated 2023. https://pubmed.ncbi.nlm.nih.gov/30725956/