Effects of continuous positive airway pressure in patients at high risk of obstructive sleep apnea during propofol sedation after spinal anesthesia

Abstract

In patients with obstructive sleep apnea, short-term use of a continuous positive airway pressure mask improves oxygenation, decreases the apnea-hypopnea index, and reduces hemodynamic instability. In this study, we investigated the effects of use of a continuous positive airway pressure mask in patients at high risk of obstructive sleep apnea during propofol sedation after spinal anesthesia. Forty patients who underwent propofol sedation after spinal anesthesia for transurethral bladder or prostate resection with a STOP-Bang score of 3 or more were enrolled in this study. Patients were randomly divided into two groups: a simple oxygen mask group (n=20) and a continuous positive airway pressure mask group (n=20). After spinal anesthesia, propofol was injected at a target concentration of 1.3mcg/ml via a target concentration control injector. ApneaLink was applied to all patients. Patients in the simple oxygen mask group were administered oxygen at a rate of 6L/min through a simple facial mask. Patients in the CPAP mask group were connected to a pressurizer, and oxygen (6L/min, 5-15cm H2O) was administered. Blood pressure, heart rate, respiratory rate, and oxygen saturation were recorded preoperatively, after spinal anesthesia, and every 5min after the injection of propofol to observe hemodynamic changes. Apnea-hypopnea index was estimated using ApneaLink. There were no significant differences in hemodynamic changes between the two groups. Apnea-hypopnea index was significantly reduced in the continuous positive airway pressure mask group compared to the simple facial mask group. Application of a continuous positive airway pressure mask in a patient at high risk of obstructive sleep apnea can lower the incidence of obstructive sleep apnea during sedation without a significant effect on hemodynamic stability.