What is cerebral perfusion pressure (CPP)?

• A. The arterial pressure in the arm.
• B. The pressure required to get oxygenated blood into the brain to perfuse the cells of the brain.
• C. The venous pressure in the brain.
• D. The pressure of cerebral spinal fluid.

Answer: (B)

Cerebral perfusion pressure is the pressure gradient that drives blood flow into the brain to nourish brain tissue. It reflects the balance between the force pushing blood into the brain (mean arterial pressure) and the opposing pressure within the skull (intracranial pressure). In simple terms, CPP is the pressure needed to get oxygenated blood into brain cells to perfuse them; if intracranial pressure rises or arterial pressure falls, CPP drops and brain tissue can become ischemic. The description that best fits this idea is the one stating it’s the pressure required to push oxygenated blood into the brain to perfuse the cells. The other options describe systemic arterial pressure, venous brain pressure, or CSF pressure, none of which capture the driving pressure for cerebral blood flow.