Determination of optimal sedation depth in sleep endoscopy with bispectrometry and simultaneous polysomnography

In this study, we aimed to evaluate the localization and configuration of vibration and obstruction in drug-induced sleep endoscopy(DISE) in obstructive sleep apnea patients and to investigate the optimal sedation depth.

The study was conducted prospectively with 42 patients. After achieving sedation with intravenous anesthetic agents, simultaneous monitoring of the patient's bispectrometry (BIS), DISE and sleep testing with a type 2 polysomnography device were performed. DISE was performed using fentanyl and midazolam, followed by propofol administered with manually controlled infusion method. The recorded data were evaluated and subjected to statistical comparisons.

It was observed that as BIS values decreased, the frequency of decreased respiratory effort and desaturation increased. Central apneas were observed with BIS values below 65 and were found to increase with deeper sedation, while with BIS values above 70, all respiratory events were obstructive apneas, with retro-palatal obstruction being the most common. It was noted that vibration occurred in over 90% of patients within the BIS range of 60-70. It was decided that the optimal sedation depth for evaluating vibration and obstruction in sleep endoscopy was within the BIS range of 60-75.

According to the results of our study, as sedation depth increases, the frequency of central apnea and desaturation increases. In our study, the sedation depth within the BIS 60-75 range was found to be the most suitable range for evaluating obstructive apnea and snoring.