In medicine, the ratio of physiologic dead space over tidal volume (VD/VT) is a routine measurement, expressing the ratio of dead-space ventilation (VD) to tidal ventilation (VT), as in physiologic research or the care of patients with respiratory disease.[1]

Equation

\frac{V_D}{V_T} = \frac{P_a \ce{CO2} - P_E \ce{CO2}}{P_a \ce{CO2}}

References

  1. ^ Raymond LW (1978). "The alveolar air equation abbreviated.". Chest. 74 (6): 675–6. doi:10.1378/chest.74.6.675. PMID 738126