In respiratory physiology, ventilation (or ventilation rate) is the rate at which gas enters or leaves the lung. It is categorised under the following definitions:
| Measurement | Symbol | Equation | Description |
| Minute ventilation | ![]() |
= tidal volume * respiratory rate[1][2] | the total volume of gas entering the lungs per minute. |
| Alveolar ventilation | ![]() |
= (tidal volume - dead space) * respiratory rate [1] | the volume of gas per unit time that reaches the alveoli, the respiratory portions of the lungs where gas exchange occurs. |
| Dead space ventilation | ![]() |
= dead space * respiratory rate[3] | is the volume of gas per unit time that does not reach these respiratory portions, but instead remains in the airways (trachea, bronchi, etc.). |
Contents |
| Measure | Sample value |
|---|---|
| Tidal volume | 0.5 L |
| Respiratory rate | 15 breaths/minute |
| Minute ventilation | 7.5 L/min |
| Dead space | 0.1667 L |
| Dead space ventilation | 2.5 L/min |
| Alveolar ventilation | 5.0 L/min |
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