Minute ventilation and alveolar ventilation in one bedside tool
Minute & Alveolar Ventilation Calculator
Calculate minute ventilation (V̇E) and alveolar ventilation (V̇A) using tidal volume, respiratory rate, and dead space. This tool is useful for bedside ventilation math, ABG interpretation, and understanding why a patient may be retaining or blowing off CO₂.
Use this alongside our Desired VE calculator, ABG Analyzer, IBW + tidal volume tool, and our Mastering ABG Analysis guide to connect ventilation math to PaCO₂ and full gas-exchange interpretation.
Calculator inputs
150 mL is a common bedside default for adult anatomic dead space, but the true value varies by patient and clinical scenario.
What this calculator helps you understand
Minute ventilation
Total air moved per minute. Useful, but it does not tell the full story about effective CO₂ clearance.
Alveolar ventilation
The more clinically useful number for CO₂ physiology, because it subtracts dead space from each breath.
Results
Why alveolar ventilation matters more than minute ventilation
Minute ventilation tells you how much air is moving in and out each minute, but alveolar ventilation tells you how much of that air is actually reaching gas-exchanging alveoli. That is why alveolar ventilation is more closely tied to PaCO₂ clearance.
Two patients can have the same minute ventilation but very different alveolar ventilation if dead space is different. This is one reason a patient can look like they are ventilating "enough" but still retain CO₂.
How this fits into the PulmTools ventilation cluster
- • Use this page to understand current ventilation
- • Use Desired VE when targeting a different PaCO₂
- • Use IBW + Tidal Volume to size protective tidal volume targets
- • Use ABG Analyzer to interpret the CO₂ result in context
- • Review Mastering ABG Analysis to connect the numbers to acid-base physiology