Fig. 3.
An example of typical adverse respiratory events observed during dental sedation in a 57-yr-old patient with body mass index of 24.3 kg/m2. Note obstructive apneas evidenced by the presence of breathing efforts and hypopneas evidenced by the presence of inspiratory (Insp.) airflow limitations. A series of coughs at the restoration of breathing immediately after an apnea appear to induce the irregular breathing and tachycardia. Oxygen saturation measured by pulse oximetry (Spo2) is maintained above 98% despite the long apneas and hypopneas. Although speculative, this is possibly due to apneic oxygenation in association with an occasional small amount of ventilation evidenced by the small respiratory fluctuations of the nasal pressure tracing (red arrows) during the apnea. Exp., expiratory.