Increased intracranial pressure reduces cerebral perfusion pressure (CPP). Which statement correctly describes CPP?

Prepare for the Platinum Emergency Medical Technician - Paramedic (EMTP) 3.3 Test. Engage with interactive questions and detailed explanations. Ace your EMT-P certification!

Multiple Choice

Increased intracranial pressure reduces cerebral perfusion pressure (CPP). Which statement correctly describes CPP?

Cerebral perfusion pressure is the pressure gradient that drives blood through the brain. It’s determined by subtracting the pressure inside the skull (intracranial pressure) from the mean arterial pressure: CPP = MAP − ICP. As ICP rises, that driving force drops, so CPP declines. If ICP climbs above the arterial pressure, the gradient can almost vanish, risking cerebral ischemia because blood can no longer flow effectively to brain tissue. That’s why maintaining MAP higher than ICP helps sustain cerebral perfusion. This isn’t controlled by heart rate alone, and the difference isn’t ICP minus MAP. It’s MAP minus ICP, so increased ICP reduces CPP rather than increasing it. Normal CPP is typically around 60–80 mmHg, with lower values risking ischemia.

Cerebral perfusion pressure is the pressure gradient that drives blood through the brain. It’s determined by subtracting the pressure inside the skull (intracranial pressure) from the mean arterial pressure: CPP = MAP − ICP. As ICP rises, that driving force drops, so CPP declines. If ICP climbs above the arterial pressure, the gradient can almost vanish, risking cerebral ischemia because blood can no longer flow effectively to brain tissue. That’s why maintaining MAP higher than ICP helps sustain cerebral perfusion.

This isn’t controlled by heart rate alone, and the difference isn’t ICP minus MAP. It’s MAP minus ICP, so increased ICP reduces CPP rather than increasing it. Normal CPP is typically around 60–80 mmHg, with lower values risking ischemia.

More practice questions