Bubble scores at rest in hypoxia. Individual subject bubble scores at rest in the left ventricle breathing FIO2 = 0.21 and after 30 min breathing FIO2 = 0.16, 0.14, 012, and 0.10. Horizontal lines indicate mode, *p < 0.01 vs. FIO2 = 0.21 (Friedman's test, Dunn's post-test). From Laurie SS, Yang X, Elliott JE, et al. Hypoxia-induced intrapulmonary arteriovenous shunting at rest in healthy humans. J Appl Physiol 2010;109(4):1072–9. © Am Physiol Soc, used with permission.