Cushing's reflex is characterized by which combination of changes?

Cushing's reflex is characterized by which combination of changes?

• A. Increase MAP with bradycardia
• B. Decrease MAP with tachycardia
• C. Increase MAP with tachycardia
• D. Decrease MAP with bradycardia

Answer: (A)

When intracranial pressure rises, cerebral perfusion pressure drops. In response, the body raises systemic arterial pressure to push blood into the brain, so mean arterial pressure increases. At the same time, the baroreceptors respond to this higher pressure with a reflex slowdown of the heart, causing bradycardia. This combination—hypertension with bradycardia—is the hallmark of the Cushing reflex (often accompanied by irregular respiration). Tachycardia or a decrease in MAP would not reflect this protective mechanism, which is why increased MAP with bradycardia is the correct description.

When intracranial pressure rises, cerebral perfusion pressure drops. In response, the body raises systemic arterial pressure to push blood into the brain, so mean arterial pressure increases. At the same time, the baroreceptors respond to this higher pressure with a reflex slowdown of the heart, causing bradycardia. This combination—hypertension with bradycardia—is the hallmark of the Cushing reflex (often accompanied by irregular respiration). Tachycardia or a decrease in MAP would not reflect this protective mechanism, which is why increased MAP with bradycardia is the correct description.