Hemodynamics & perfusion tool

Perfusion pressure and early circulatory stress in one bedside calculator

MAP + Shock Index Calculator

Calculate mean arterial pressure (MAP) and shock index from blood pressure and heart rate. This tool helps you think about perfusion, hemodynamic instability, and whether a patient may be showing early signs of shock or circulatory stress.

Use it alongside the Fick cardiac output calculator, P/F Ratio & Oxygenation Index tool, ABG Analyzer, and our inhaled nitric oxide guide when evaluating oxygen delivery, perfusion, and the broader ICU picture.

MAP formula
DBP + 1/3(SBP − DBP)
Shock index
HR ÷ SBP
Why it matters
Pressure and pulse alone can miss early instability

Calculator inputs

What this page helps you understand

MAP

Mean arterial pressure is a fast bedside estimate of perfusion pressure and is commonly referenced when thinking about organ perfusion.

Shock Index

Shock index can reveal circulatory stress earlier than blood pressure alone by combining heart rate and systolic pressure into one quick ratio.

Results

Enter your values and click Calculate Hemodynamics to generate results.

Why MAP matters

MAP is often used as a quick bedside estimate of organ perfusion pressure. It is not a perfect reflection of tissue perfusion, but it remains one of the most common hemodynamic reference points in critical care.

In many ICU settings, a MAP below 65 mmHg raises concern for inadequate perfusion, especially in sepsis or shock states, though the right target still depends on the patient.

Why shock index matters

Shock index can flag hemodynamic stress before blood pressure looks dramatically abnormal. A patient with tachycardia and a “normal” systolic pressure may still be compensating hard.

That is why shock index is useful for early bedside pattern recognition, especially when paired with clinical exam, mental status, perfusion findings, lactate, and trend data.

Related guides

MAP + Shock Index Calculator | Hemodynamics Tool | PulmTools