Supraglottic Airway Devices:
Supraglottic airway devices have become invaluable for both routine and difficult airway management. After the introduction of the laryngeal mask airway (LMA) classic in the 1980s, there has been a steady increase in the applications for use of supraglottic airways as well as incidence of use. According to the fourth national project, in the UK they are used in approximately 56% of general anesthetics.
Elective Airway Management:
For routine airway management, advantages over endotracheal intubation include fast placement without the need of a laryngoscope, less hemodynamic changes with insertion and removal, less coughing or bucking with removal, no need for muscle relaxants, preserved laryngeal competence and mucociliary function, and less laryngeal trauma.
Difficult Airway Management:
Supraglottic airways can be a life saving tool for oxygenation and ventilation as a rescue device in a “cannot intubate, cannot ventilate” situation. They can also be a conduit for intubation in a difficult airway scenarios.When other oxygenation or ventilation techniques have failed, a supraglottic airway device may succeed as a rescue device as several of the risk factors for difficult facemask ventilation and difficult intubation are not risks for difficult supraglottic airway placement.
Relative contraindications include non-supine positioning, obese and pregnant patients, patients with increased risk for regurgitation of gastric contents, intra-abdominal or airway procedures and long duration of surgery. Supraglottic airways have been successfully used in patients with these relative contraindications, but the risk versus benefit of use in these situations must be considered.
Aspiration is a concern with supraglottic airway placement. This risk of aspiration increases with high airway pressures, gastric inflation and poor airway positioning over the glottic opening. Complications of laryngeal mask airways in patients with difficult airways include bronchospasm, postoperative swallowing difficulties, respiratory obstruction, laryngeal nerve injury, edema, and hypoglossal nerve paralysis.
Types of Supraglottic Airways:
There are many different types of supraglottic airway devices in single-use and reusable forms, including intubating supraglottic airways and supraglottic airways allowing gastric decompression. Supraglottic airway devices are sized according to the patient’s weight, and sizes vary by manufacturer.
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