Minute Ventilation Calculator
Rate × tidal volume — the total gas moved per minute, and (with dead space) how much of it actually ventilates alveoli.
Written by Apex Respiratory Editorial Team
Optional — ≈ 1 mL/lb IBW.
Enter rate and tidal volume to calculate V̇E.
V̇E vs V̇A — the dead space catch
Minute ventilation counts every liter, including the ~1 mL/lb of predicted weight that fills conducting airways and never reaches a capillary. Rapid-shallow patterns waste a growing fraction of V̇E on dead space — the same 7 L/min moves far less alveolar gas at VT 250 × RR 28 than at VT 500 × RR 14.
PaCO₂ tracks alveolar ventilation, not V̇E. A rising PaCO₂ despite a “normal” V̇E usually means dead space is winning.
Educational use only. This material supports respiratory therapy education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional protocols, or physician orders. Always follow facility policies and current provider orders, and verify calculations independently before clinical use.
Sources
- Kacmarek RM, Stoller JK, Heuer AJ. Egan's Fundamentals of Respiratory Care. 12th ed. Elsevier; 2021. Ventilation chapters.
- Hess DR, Kacmarek RM. Essentials of Mechanical Ventilation. 4th ed. McGraw-Hill; 2019.