Nasopharyngeal Tube Effects On Breathing During Sedation For Dental Procedures A Randomized Controlled Trial

Background: Intravenous sedation is effective in patients undergoing dental procedures, but fatal hypoxemic events have been documented. It was hypothesized that abnormal breathing events occur frequently and are underdetected by pulse oximetry during sedation for dental procedures (primary hypothesis) and that insertion of a small-diameter nasopharyngeal tube reduces the frequency of the abnormal breathing events (secondary hypothesis).Methods: In this nonblinded randomized control study, frequency of abnormal breathing episodes per hour (abnormal breathing index) of the patients under sedation for dental procedures was determined and used as a primary outcome to test the hypotheses. Abnormal breathing indexes were measured by a portable sleep monitor. Of the 46 participants, 43 were randomly allocated to the control group (n = 23, no nasopharyngeal tube) and the nasopharyngeal tube group (n = 20).Results: In the control group, nondesaturated abnormal breathing index was higher than the wdesaturated abnormal breathing index (35.2 [20.6, 48.0] vs. 7.2 [4.1, 18.5] h(-1), difference: 25.1 [95% CI, 13.8 to 36.4], P < 0.001). The obstructive abnormal breathing index was greater than central abnormal breathing index (P < 0.001), and half of abnormal breathing indexes were followed by irregular breathing. Despite the obstructive nature of abnormal breathing, the nasopharyngeal tube did not significantly reduce the abnormal breathing index (48.0 [33.8, 64.4] h(-1) vs. 50.5 [36.4, 63.9] h(-1), difference: -2.0 [95% CI, -15.2 to 11.2], P = 0.846), not supporting the secondary hypothesis.Conclusions: Patients under sedation for dental procedure frequently encounter obstructive apnea/hypopnea events. The majority of the obstructive apnea/hypopnea events were not detectable by pulse oximetry. The effectiveness of a small-diameter nasopharyngeal tube to mitigate the events is limited.