How does fever affect brain injury risk after stroke?

How does fever affect brain injury risk after stroke?

• A. Fever reduces brain injury risk
• B. Fever increases metabolic demand, which may increase risk of brain injury
• C. Fever has no effect on stroke outcomes
• D. Fever improves perfusion

Answer: (B)

Fever after a stroke raises brain metabolic demand. In areas where blood flow is already reduced, neurons rely on limited energy supply. When fever pushes metabolic needs higher, oxygen and glucose delivery can’t keep up, leading to energy failure, more cell death, and larger infarcts. Fever also fuels inflammatory responses and edema that worsen tissue injury. That’s why fever increases brain injury risk after stroke. The other statements don’t fit because fever does not lessen risk, it does have an effect, and it does not improve perfusion.

Fever after a stroke raises brain metabolic demand. In areas where blood flow is already reduced, neurons rely on limited energy supply. When fever pushes metabolic needs higher, oxygen and glucose delivery can’t keep up, leading to energy failure, more cell death, and larger infarcts. Fever also fuels inflammatory responses and edema that worsen tissue injury. That’s why fever increases brain injury risk after stroke. The other statements don’t fit because fever does not lessen risk, it does have an effect, and it does not improve perfusion.