Eli5: mean arterial pressure


Eli5: mean arterial pressure

In: 2

Mean Arterial Pressure ≈ Diastolic Pressure + ⅓Pulse Pressure. It’s just an average of the different pressures, the diastolic being active more time it weights more in the equation.

blood pressure is usually shown as two numbers, e.g. 140/90 – the first and higher number is what we call the systolic blood pressure, and it’s a measure of the blood pressure in your blood vessels just after the heart has pumped out a bunch of blood (think of it as the highest possible pressure immediately after a heartbeat); the second and lower number is the diastolic blood pressure, and it measures the blood pressure in blood vessels when the heart is filling up with blood (i.e. the lower end of the blood pressure).

mean arterial pressure is a single number meant to reflect the average pressure across one entire cycle (there’s a specific formula which you can google). this is important because sometimes the systolic and diastolic pressures can diverge (e.g. one goes up, one goes down). there are also some guidelines that specifically use MAP rather than BP. MAP is particular important in determining the cerebral perfusion pressure (a rough gauge of how good the perfusion is to the brain).