Health
MAP Calculator FAQ
Manual SBP/DBP entry, instant MAP, pulse pressure, Shock Index, and SOFA cardiovascular reference.
FAQ
How is MAP calculated?+
MAP = DBP + 1/3 × (SBP - DBP). This formula estimates the average arterial pressure during a single cardiac cycle by weighting diastole more heavily than systole, since the heart spends about two-thirds of the cycle in diastole. The calculator displays both the raw formula and the worked substitution using your actual values so you can verify the math.
What MAP is considered low?+
A common adult reference band is 65–100 mmHg for normal perfusion. The calculator separates the low range into two bands: 60–64 mmHg (borderline low) and below 60 mmHg (critical). This follows standard clinical teaching that MAP must stay above 60 mmHg to perfuse the coronary arteries and kidneys adequately.
Does the unit toggle convert the values?+
Yes. When you switch between mmHg and kPa, both the SBP and DBP inputs are converted automatically using the standard conversion factor (1 mmHg = 0.133322 kPa). The MAP and pulse pressure results update to stay aligned with the chosen unit. This is useful when working with devices or records that report in different units.
Why does the page show a SOFA cardiovascular reference?+
The SOFA (Sequential Organ Failure Assessment) score uses a MAP below 70 mmHg as the threshold for the cardiovascular component, assigning points when vasopressors are required to maintain MAP above this level. The calculator surfaces this reference when your result drops below 70 mmHg, giving clinical context without scoring the full SOFA assessment.
Is qSOFA or dosing guidance included?+
No. This version stays focused on manual MAP calculation, reference band display, and session-only history tracking. It does not include a qSOFA calculation module, vasopressor dosing guidance, or medication recommendations. The calculator is designed as a quick bedside reference tool rather than a comprehensive clinical decision support system.
What is the Shock Index and how is it used?+
Shock Index is calculated as heart rate divided by systolic blood pressure (HR / SBP). A value above 1.0 is traditionally considered abnormal and may suggest hemodynamic instability or early compensated shock. The calculator computes this when you enter a heart rate. Like MAP, Shock Index is a screening tool and should be interpreted alongside the full clinical picture.
What is pulse pressure and why does it matter?+
Pulse pressure is the difference between systolic and diastolic pressure (SBP - DBP). A normal pulse pressure is 30–50 mmHg. A wide pulse pressure (over 60 mmHg) can indicate aortic regurgitation, arterial stiffness, or hyperthyroidism. A narrow pulse pressure (under 30 mmHg) may suggest cardiac tamponade, heart failure, or significant blood loss. The calculator displays pulse pressure alongside MAP for quick reference.