Capnography Prevents Hypoxia during Sedation for Dental Treatment: A Randomized Controlled Trial

Intravenous sedation is useful for dental treatment in patients with intellectual disabilities. However, it is often necessary to manage such patients with deep sedation because their cooperation cannot be obtained. During deep sedation, undetected hypoventilation can lead to severe complications, such as hypoxia. Recently, capnographic monitoring has been advocated as a useful technique for preventing hypoxia during sedation. This randomized control trial evaluated whether the use of capnography reduces the incidence of hypoxia during the deep sedation of patients for dental treatment. This study involved patients with intellectual disabilities who underwent dental treatment under sedation. The subjects were randomized to the intervention group (I-group) or control group (C-group). All of the patients underwent routine monitoring, as well as bispectral index (BIS) and capnographic monitoring; however, only an independent observer had access to the patients' capnographic data during the dental procedures. Sedation was maintained at a BIS of 50 to 70 by administration of propofol. In the I-group, the independent observer signaled to the dental anesthesiologist if the capnogram indicated that the patient had been suffering from alveolar hypoventilation or apnea for >15 s. In the C-group, the observer signaled to the dental anesthesiologist if the capnogram indicated that the patient had been suffering from alveolar hypoventilation or apnea for >60 s. In both groups, the dental anesthesiologists responded to the signals using appropriate airway management strategies. The primary endpoint of this study was the incidence of hypoxia during dental treatment, which was defined as oxygen saturation of <95%. Hypoxemic episodes occurred in 13.4% and 34.8% of cases in the I-group and C-group, respectively. The incidence of hypoxia was significantly lower in the I-group. These results suggest that capnographic monitoring during deep sedation for dental treatment prevents hypoxemic episodes by allowing the early detection of hypoventilation. Knowledge Transfer Statement: This is the first randomized controlled trial to examine whether the use of capnography reduces the incidence of hypoxia during deep sedation for dental treatment. The findings of this study can be used by clinicians to aid decision-making regarding dental sedation standards at individual clinics. Moreover, they can be used as high-level evidence during the production or updating of clinical guidelines for dental sedation by leading associations.