Perioperative considerations in the management of obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is characterised by repetitive compromise of the upper airway, causing impaired ventilation, sleep fragmentation, and daytime functional impairment. It is a heterogeneous condition encompassing different phenotypes. The prevalence of OSA among patients presenting for elective surgery is growing, largely attributable to an increase in age and obesity rates, and most patients remain undiagnosed and untreated at the time of surgery. This condition is an established risk factor for increased perioperative cardiopulmonary morbidity, heightened in the presence of concurrent medical comorbidities. Therefore, it is important to perform preoperative OSA screening and risk stratification - using the STOP-Bang screening questionnaire, nocturnal oximetry, and ambulatory and in-laboratory polysomnography, for example. Postoperative risk assessment is an evolving process that encompasses evaluation of upper airway compromise, ventilatory control instability, and pain-sedation mismatch. Optimal postoperative OSA management comprises continuation of regular positive airway pressure, a multimodal opioid-sparing analgesia strategy to limit respiratory depression, avoidance of supine position, and cautious intravenous fluid administration. Supplemental oxygen does not replace a patient's regular positive airway pressure therapy and should be administered cautiously to avoid risk of hypoventilation and worsening of hypercapnia. Continuous pulse oximetry monitoring with specified targets of peripheral oxygen saturation measured by pulse oximetry is encouraged.