Mean arterial pressure

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The mean arterial pressure (MAP) is a term used in medicine to describe a notional average blood pressure in an individual. It is defined as the average arterial pressure during a single cardiac cycle.

1 Calculation
2 Estimation
3 Clinical significance
4 See also
5 References

[edit] Calculation

$MAP = (CO \times SVR) + CVP$ , where^[1]

$C V P$ is usually small enough to be neglected in this formula.

[edit] Estimation

At normal resting heart rates $M A P$ can be approximated using the more easily measured systolic and diastolic pressures, $S P$ and $D P$ :^[2]

$MAP \simeq DP + \frac{1}{3}(SP - DP)$

MAP = [(2 x diastolic) + systolic] / 3

or equivalently

$MAP \simeq DP + \frac{1}{3}PP$

where $P P$ is the pulse pressure, $S P - D P$

At high heart rates $M A P$ is more closely approximated by the arithmetic mean of systolic and diastolic pressures because of the change in shape of the arterial pressure pulse.