Fig. 1

Graph a shows the comparison of cuff pressures between the three different lubrication conditions (0 g, 1.0 g and 3.0 g of K-Y™ jelly) under continuous flushing with nitrous oxide. Grey, black, and white bars in Graph a represent the cuff pressures with lubrication with 0 g, 1.0 g and 3.0 g of K-Y™ jelly. Data are expressed as mean (SD) in Graph a. P-values < 0.0167 (0.05/3) were considered statistically significant in the post hoc comparison of the three groups at each time point. Graph b shows the comparison of the inhibitory rates (%) of 1.0 g K-Y™ jelly with those of 3.0 g K-Y™ jelly. The horizontal bars, the boxes, and the whiskers represent the median, IQR, and ranges, respectively in Graph B. P-value < 0.05 was considered statistically significant. *P < 0.05 and ***P < 0.0001