Mean Arterial Pressure — Instant, Clinical & Mobile-First
Clinical Information
Interpretation & Thresholds
Mean Arterial Pressure (MAP) is the average pressure in the arteries during a cardiac cycle. It's a key indicator of blood flow to vital organs.
Clinical thresholds:
- <60 mmHg — concerning for organ hypoperfusion
- ~65 mmHg — typical target in septic shock resuscitation
- 70–100 mmHg — common normal range
Quick Examples
Here are common blood pressure readings and their calculated MAP values:
- 120 / 80 → MAP = 93.3 mmHg
- 90 / 60 → MAP = 70 mmHg
- 80 / 50 → MAP = 60 mmHg
About MAP
MAP is calculated using the formula: MAP ≈ DBP + (SBP − DBP) / 3
This formula weights diastolic pressure more because the cardiac cycle spends more time in diastole than systole.
Mean Arterial Pressure (MAP) Calculator — Clinical Guide & Interpretation
Mean arterial pressure (MAP) is the average pressure in the arteries during a single cardiac cycle and serves as a practical indicator for organ perfusion — the force that pushes oxygenated blood into tissues like the brain, kidneys and heart. MAP is expressed in millimeters of mercury (mmHg) and is commonly estimated using a simple formula that uses the measured systolic (SBP) and diastolic (DBP) blood pressures.
How this MAP calculator works
This tool uses the standard clinical formula: MAP ≈ DBP + (SBP − DBP) / 3 (equivalently (SBP + 2×DBP)/3). The formula weights diastolic pressure more because the cardiac cycle spends a greater proportion of time in diastole than systole. The result is shown to one decimal place for clarity and clinical readability.
Why MAP matters
MAP is a simple summary metric to evaluate whether organs are receiving sufficient blood flow. Low MAP values can indicate inadequate perfusion and risk to organs; high MAP values are typically associated with hypertension and increased vascular load. Clinicians use MAP together with clinical signs — urine output, mental status and lactate levels — when making resuscitation and treatment decisions.
Common thresholds and clinical context
While exact targets vary by patient, common practical thresholds include:
- <60 mmHg — risk of inadequate organ perfusion; concerning in most adults.
- ~65 mmHg — starting MAP target in many septic shock protocols when using vasopressors.
- 70–100 mmHg — typical normal range for ambulatory adults.
Examples
Quick calculation examples:
- SBP 120 / DBP 80 → MAP = 80 + (120 − 80)/3 = 93.3 mmHg
- SBP 90 / DBP 60 → MAP = 60 + (90 − 60)/3 = 70 mmHg
- SBP 80 / DBP 50 → MAP = 50 + (80 − 50)/3 = 60 mmHg
Limitations
The formula is an approximation suitable for outpatient screening and general clinical use. It can be less accurate in situations with very high heart rates, arrhythmias, or when arterial waveform analysis is available — in such cases invasive arterial monitoring or waveform-based calculations provide more precise MAP values.
How to measure BP for best accuracy
- Use a validated blood pressure device and follow the manufacturer’s instructions.
- Sit quietly for 5 minutes before measuring; ensure cuff at heart level and correct cuff size.
- Take 2–3 readings and use the average for better reliability.
Sources & trusted references
For further clinical reading and guideline context, see StatPearls (mean arterial pressure review) and the Surviving Sepsis Campaign guidelines for MAP targets in septic shock: StatPearls (NCBI), Surviving Sepsis Campaign.
Disclaimer: This calculator provides an educational estimate only and is not a substitute for professional medical evaluation. If you are symptomatic or have signs of instability, seek immediate medical care.