Why MAP Matters More Than Regular BP
While Systolic Blood Pressure measures the "peak" pressure during a heartbeat, Mean Arterial Pressure (MAP) measures the constant, average pressure pushing blood to your vital organs.
In critical care scenarios like sepsis or trauma, MAP is often considered the "source of truth" for organ perfusion. If the MAP drops too low, organs like the kidneys and brain begin to starve of oxygen, regardless of what the Systolic number says.
The "Doubling Logic"
The formula is (Systolic + 2 × Diastolic) / 3. Why do we double the Diastolic? Because the heart spends twice as much time resting (Diastole) as it does pumping (Systole) during a normal cardiac cycle.
Normal & Critical Ranges
This is the standard target for sepsis management set by the Surviving Sepsis Campaign. Maintaining a MAP above 65 is generally sufficient to perfuse organs.
At this level, perfusion to vital organs (especially the kidneys) may be compromised. Prolonged time in this zone significantly increases the risk of mortality and acute kidney injury.
Elevated MAP indicates high vascular resistance or fluid overload, which increases cardiac workload and can damage vessel walls over time.
Frequently Asked Questions
Why is 65 the magic number?
Can I have a normal BP but low MAP?
Is this accurate for irregular heartbeats?
Tools & Data Verified by the EverydayCalculators Clinical Team.
Last updated: January 2026.