Fig. 2. Physiologic effects of inhaled NO (40 ppm) during hypoxia in nine healthy volunteers. Note the decrease of mean pulmonary artery pressure and pulmonary vascular resistance achieved by NO inhalation. Values are mean ± SE. LVSWI = left ventricular stroke work index; Pa^O2= arterial partial pressure of oxygen, Pa^CO2= arterial partial pressure of carbon dioxide; PCWP = pulmonary capillary wedge pressure; PPA = mean pulmonary artery pressure; PVR = pulmonary vascular resistance; RVSWI = right ventricular stroke work index. Reprinted with permission from Frostell  et al. 139