Mean arterial pressure and average blood pressure

Abstract

Mean arterial pressure (MAP) and average blood pressure (ABP) are compared. MAP is normally computed as some weighted mean of systolic and diastolic pressures. Average blood pressure is defined here as the area under the pressure pulse contour divided by the duration of the heart cycle. Using equations for the pressure pulse contour found in the literature, a closed-form solution for the ABP was developed and compared to the expression for MAP. It is shown that, in general, MAP and ABP are different; that MAP can underestimate or overestimate ABP depending upon how the systolic and diastolic pressures are weighted. In the case of a normal adult with a pressure of 120/80 mm of mercury, the difference between MAP and ABP is on the order of 6 to 8%. It is conjectured that the error would be larger in the hypertensive patients.<>