how do you calculate physiological dead space

In physiology, dead space is the volume of air which is inhaled that does not take part in the gas exchange, either because it (1) remains in the conducting airways, or (2) reaches alveoli that are not perfused or poorly perfused. PeCO2 is the partial pressure of carbon dioxide in exhaled air.

PaCO2 is the partial pressure of carbon dioxide in arterial blood.

The Bohr Method formula for the Physiologic Dead Space is:

However, this can be automatically converted to compatible units via the pull-down menu. Volume of Dead Space (V D): The calculator returns the volume in milliliters (ml). ( PeCO2) This is the partial pressure of carbon dioxide in exhaled air.( PaCO2) This is the partial pressure of carbon dioxide in arterial blood.INSTRUCTIONS: Choose units and enter the following: The Physiologic Dead Space (Bohr Method) calculator computes the volume of dead space (V D) based on the tidal volume (V T) and the partial pressures of carbon dioxide in arterial blood, exhaled air and ambient air.

How do you calculate physiological dead space