Question

Blood pressure is typically taken when a patient is at rest. By using the systolic and d’astolic pressure values, we can calculate the Mean Arterial Pressure (MAP). But MAP is not just an average of the sum of the two pressures. The calculation is MAP= DP + (PP/3). Why do we use this calculation?

Answer 1

Mean Arterial Pressure (MAP) is not a simple average of systolic and diastolic pressures because the heart spends more time in diastole. Therefore, MAP is calculated by adding diastolic pressure to one-third of the pulse pressure for a more accurate indication of the blood's driving force through the body.

Step-by-step explanation:

The calculation of Mean Arterial Pressure (MAP) does not simply average the systolic and diastolic pressures because blood pressure is highest during systole and lowest during diastole, and the heart spends more time in diastole.

Thus, MAP is calculated by adding the diastolic pressure (DP) to one-third of the pulse pressure (PP), which is the difference between the systolic and diastolic pressures. MAP = DP + (PP/3) provides a more accurate representation of the overall driving force that pushes blood through the circulatory system.