A simple two-compartment alveolar model containing a shunt compartment and a normal alveolar unit
Compartment 1 (shunt) | Compartment 2 (ventilated) | Combined output | |
V′A | 0.0 L·min−1 | 4.5 L·min−1 | 4.5 L·min−1 |
Q′ | 1.5 L·min−1 | 3.0 L·min−1 | 4.5 L·min−1 |
V′A/Q′ | 0.0 L·L−1 | 1.5 L·L−1 | 1.0 L·L−1 |
PaCO2 | 46 mmHg | 37 mmHg | 40 mmHg |
PACO2 | 46 mmHg | 37 mmHg | 37 mmHg |
Alveolar VD/VT | 7.5% |
V′A: alveolar ventilation; Q′: perfusion; PaCO2: arterial CO2 tension; PACO2: alveolar CO2 tension; VD/VT: alveolar dead space.