An astronaut experiences sustained microgravity during a prolonged space mission. Which risk increases as blood redistributes cephalad (towards the head)?

💡 Explanation

The risk of increased intracranial pressure increases because cephalad blood redistribution results in increased cerebral blood volume. This initiates the Monro-Kellie doctrine mechanism within the rigid skull, therefore increasing intracranial pressure, rather than edema in limbs or affecting red blood cell production.

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