What is the correct formula to calculate mean arterial pressure (MAP)?

What is the correct formula to calculate mean arterial pressure (MAP)?

• A. 2xdiastolic + systolic all divided by 3
• B. (Systolic + Diastolic) / 2
• C. (2x Systolic + Diastolic) / 3
• D. Systolic + 2x Diastolic / 3

Answer: (A)

Mean arterial pressure reflects the average pressure in the arteries during a cardiac cycle and correlates with organ perfusion better than a simple average of systolic and diastolic pressures. Because diastole lasts longer than systole, diastolic pressure is weighted more heavily. The correct formula is MAP ≈ (Systolic + 2 × Diastolic) ÷ 3, which is the same as (2 × Diastolic + Systolic) ÷ 3. For example, with a systolic of 120 and a diastolic of 80, MAP ≈ (120 + 2×80)/3 = 280/3 ≈ 93 mmHg. The other formulas either average the pressures equally or weight systolic incorrectly, so they don’t provide the accurate estimate of mean arterial pressure.

Mean arterial pressure reflects the average pressure in the arteries during a cardiac cycle and correlates with organ perfusion better than a simple average of systolic and diastolic pressures. Because diastole lasts longer than systole, diastolic pressure is weighted more heavily. The correct formula is MAP ≈ (Systolic + 2 × Diastolic) ÷ 3, which is the same as (2 × Diastolic + Systolic) ÷ 3. For example, with a systolic of 120 and a diastolic of 80, MAP ≈ (120 + 2×80)/3 = 280/3 ≈ 93 mmHg. The other formulas either average the pressures equally or weight systolic incorrectly, so they don’t provide the accurate estimate of mean arterial pressure.