Obstructive sleep apnoea syndrome: What the anesthesiologist should know

Obstructive sleep apnoea syndrome (OSAS) is a rather common sleep disorder and constitutes a risk or an aggravating factor for various underlying diseases. OSAS is characterised by repeated upper airway collapse during sleep causing fragmented sleep, hypoxemia and hypercapnia. It may also cause considerable changes in intrathoracic pressure and an increase in sympathetic nervous activity, which represent the basis of associated pathologies such as arterial hypertension, ischaemic heart disease, diabetes mellitus, stroke and sudden death [1]. Moreover, there is a wellestablished association between OSAS and postoperative complications [2, 3]. Nevertheless, a significant proportion of patients affected by OSAS undergo surgery without diagnosis and, consequently, without therapy [4]. Therefore, it is crucial for the anaesthesiologist to identify patients at risk of OSAS before surgery for a correct definition of a perioperative strategy to reduce the risk of perioperative complication. This process should be done independently and regardless of whether the patient undergoes general or locoregional anaesthesia.