Mean Arterial Pressure (MAP)

What This Calculator Measures

Calculates mean arterial pressure (MAP), the average pressure driving perfusion of vital organs, from systolic and diastolic blood pressure.

How to Use

1. Measure the systolic and diastolic blood pressure.
2. Enter both values.
3. Review the calculated MAP against normal values and perfusion targets.

Interpretation Guide

Normal resting MAP is approximately 70–100 mmHg. In sepsis and septic shock, a MAP ≥ 65 mmHg is a commonly cited target to support organ perfusion. Very low MAP raises concern for organ hypoperfusion, while the optimal target varies with the patient's baseline blood pressure and condition.

Clinical Significance

MAP reflects the driving pressure for organ perfusion more closely than systolic or diastolic pressure alone and is a central parameter in resuscitation and vasopressor management.

When to Use

• Hemodynamic assessment in the critically ill
• Guiding blood pressure targets in sepsis and shock
• Monitoring vasopressor therapy
• Assessing the risk of organ hypoperfusion

When Not to Use

• As a substitute for full hemodynamic monitoring (cardiac output, lactate, urine output)
• In isolation without clinical context

Limitations

• The formula estimates MAP from a formula rather than a direct measurement.
• It is less reliable with wide pulse pressures or very high heart rates.
• Optimal MAP targets vary by patient and condition (e.g., chronic hypertension, age).
• Does not reflect the adequacy of cardiac output or tissue perfusion.

Worked Example

A 60-year-old man with septic shock has a blood pressure of 90/60 mmHg.

MAP = (90 + 2 × 60) / 3 = 70 mmHg, meeting the commonly cited ≥ 65 mmHg perfusion target in sepsis.

Evidence

Source

Original MAP Formula / SSC Guidelines

Reference

Meaney E, Alva F, Moguel R, et al. Formula and nomogram for the sphygmomanometric calculation of the mean arterial pressure. Heart. 2000;84(1):64.

Reviewed By

MedCalcHub Clinical Team

Version

1.0

Updated

2026-08

1. Meaney E, et al. Heart. 2000;84(1):64.
2. Evans L, et al. Crit Care Med. 2021;49(11):e1063-e1143.

References

1. Meaney E, Alva F, Moguel R, et al. Formula and nomogram for the sphygmomanometric calculation of the mean arterial pressure. Heart. 2000;84(1):64. (Original Description)
2. Evans L, et al. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Crit Care Med. 2021;49(11):e1063-e1143. (Guideline)

Frequently Asked Questions