VD/VT

In medicine, the ratio of physiologic dead space over tidal volume (V_D/V_T) is a routine measurement, expressing the ratio of dead-space ventilation (V_D) to tidal ventilation (V_T), 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

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

[pmid738126-1] Raymond LW (1978). "The alveolar air equation abbreviated". Chest. 74 (6): 675–6. doi:10.1378/chest.74.6.675. PMID 738126.

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