Fig. 7.
Box plots presenting effects of nasopharyngeal tube insertion on abdominal breathing index and duration of abnormal breathing during dental sedation. Median values are indicated by a horizontal bar within each box; bars above and below each box represent 25 and 75 percentiles, ends of vertical lines denote 5 and 95 percentiles, and black circles are outliers. Comparisons within the feature were performed by Mann–Whitney rank sum test. Note the significant increase of hypopneic abnormal breathing index in the nasopharyngeal tube group despite no difference of total abdominal breathing index. There was a significant interaction between changes of apneic and hypopneic abnormal breathing indexes for presence or absence of the nasopharyngeal tube (P = 0.001).