
| Respiratory rate in breaths/min (RR) | |
| Peak Inspiratory Pressure (PIP) | |
| unit | Torr/mmHg kPa cmH20 |
| Peak End Expiratory Pressure (PEEP) | |
| unit | Torr/mmHg kPa cmH20 |
| Pressure of CO2 (PaCo2) | |
| unit | Torr/mmHg kPa cmH20 |

Ventilation Index (VI) is calculated using initial ventilator settings (respiratory rate(RR), peak inspiratory pressure (PIP), and positive end-expiratory pressure (PEEP) and partial pressure of carbon dioxide in arterial blood (PaCO2).
Formula:
Interpretation:
References: