Supraglottic Airway Devices: A Review in a New Era of Airway Management

‘Supraglottic Airway Devices’ refers to a broad set of medical devices capable of acting as a passageway for ventilation, oxygenation and administration of anaesthetic gases. Their adoption has increased gradually over the last decades, having become a fundamental tool in modern anaesthesiology. Brain's 'Laryngeal Mask Airway', introduced in 1983, marked the beginning of a revolution as a new method for airway management, ultimately replacing tracheal intubation as the most used. Initially targeted for simple procedures, supraglottic airway devices (SADs) have been gaining new indications, as many advanced models were introduced with specific designs for better ventilatory performance and higher patient safety. SADs also prove to be useful in critical scenarios both in emergencies, as rescue airways in difficult intubation. Their higher ease and speed of insertion, lower autonomic impact and less post-operative discomfort for the patient are seen as some of the best advantages when compared to the endotracheal tube (ET), but studies with some SADs have shown lower seal pressures and higher incidence of gastric insufflation. There is still not enough evidence to prove that the newer SADs can provide the same level of safety against pulmonary aspiration as the ET. Main advantages in relation to the facemask are easier placement, more reliable ventilation and hands-free operation. Several SADs have features better suited for some scenarios, which has led to a substantial amount of devices available at the same time, being the anaesthetist the responsible for its selection. This demands the knowledge of their specificities and since new devices are always being introduced, continuous learning is paramount. Sometimes the newest devices become available before any evidence is published on them. Attempts at devising a useful classification system have not been completely successful with several different taxonomies proposed but still no agreement among the experts.