Figure 3.

Hydraulic model of carbon dioxide kinetics in the body. Large peripheral tissue carbon dioxide compartment (left) drains through cardiac output ( T) into the smaller central pulmonary carbon dioxide compartment (right). FCO2, fractional carbon dioxide; FRC, functional residual capacity; PaCO₂ arterial PCO₂; P CO₂, mixed venous PCO₂; ♵A/ , ventilation : perfusion ratio; VCO_2,ti, tissue carbon dioxide production; VD_ana, anatomical dead space; ♵E, exhaled ventilation (see text). Adapted from Breen and Mazumdar [3].