Figure 2

MIGET results typical of patients with common cardiopulmonary disorders. (A) MIGET results typical of patients with moderate asthma. Bottom panel: retention and excretion curves, showing the gases used (solid circles). Compared to homogeneous, retention of lower solubility gases is increased (arrow). Top panel: the associated ${\dot{V}}_{\mathrm{A}}/\dot{Q}$ distribution, showing the appearance of areas of low ${\dot{V}}_{\mathrm{A}}/\dot{Q}$. (B) MIGET results typical of patients with either emphysema or pulmonary embolism. Bottom panel: retention and excretion curves, showing the gases used (solid circles). Compared to homogeneous, excretion of higher solubility gases is decreased (arrow). Top panel: the associated ${\dot{V}}_{\mathrm{A}}/\dot{Q}$ distribution, showing the appearance of areas of high ${\dot{V}}_{\mathrm{A}}/\dot{Q}$. (C) MIGET results typical of patients with interstitial pulmonary fibrosis. Areas of zero (i.e., shunt) and also very low ${\dot{V}}_{\mathrm{A}}/\dot{Q}$ ratio are common, but the pattern is quite different from that seen in asthma (Figure 2A). (D) MIGET results typical of patients with acute lung injury. Areas of zero (i.e., shunt) and also very low ${\dot{V}}_{\mathrm{A}}/\dot{Q}$ ratio are common, as are high ${\dot{V}}_{\mathrm{A}}/\dot{Q}$ regions.