“…Since ciliated surfaces are responsible for clearing mucus from the lungs, oxygen-mediated damage to those surfaces may impair mucus clearance, an important line of defense against infection and harmful particulate matter. Very high levels of oxygen can lead to histologically evident changes in respiratory epithelium, such as deciliation, 15 and increased thickness of epithelium and smooth muscle layer. 16,17 However, the consequences of those changes on directional flow rates at the ∼100 to 1000 μm size scale are not well understood.…”