Figure 1.

Theoretical calculations based on the classical shunt equation: (a) Effect of venous admixture or pulmonary shunt fraction (${\dot{Q}}_S/{\dot{Q}}_T$) on arterial oxygen content (CaO₂) for a given mixed venous oxygen content ($C\overline{v}{O}_2$) assuming ideal pulmonary capillary oxygen content is 0.20 L/L; (b) effect of $C\overline{v}{O}_2$ on CaO₂ for a given ${\dot{Q}}_S/{\dot{Q}}_T$ also assuming ideal pulmonary capillary oxygen content is 0.20 L/L; and (c) effect of an arteriovenous stula expressed as a fraction of cardiac output (${\dot{Q}}_F/{\dot{Q}}_T$) on $C\overline{v}{O}_2$ for a given CaO₂ assuming systemic capillary oxygen content is 0.15 L/L.