They are most commonly used by anaesthetists to channel oxygen or inhalational anaesthetic to the lungs during surgery and in the pre-hospital setting (for instance by paramedics and emergency medical technicians) for unconscious patients.
[citation needed] A laryngeal mask is composed of an airway tube that connects to an elliptical mask with a cuff which is inserted through the patient's mouth, down the windpipe, and once deployed forms an airtight seal on top the glottis (unlike tracheal tubes which pass through the glottis) allowing a secure airway to be managed by a health care provider.
[2] A laryngeal mask airway is generally not used in surgeries where there is a high risk that stomach contents may be aspirated.
[1] More serious complications include vomiting while the laryngeal mask airway is in place (potentially leading to aspiration of stomach contents).
[1] Although the laryngeal mask airway is specifically designed to be easy to place, it is possible for the ventilation it provides to be inadequate.
[citation needed] A laryngeal mask airway must first be completely sterilised (it may be reused many times).
[1] A pen-like grip is used to move it through the patient's mouth and throat, preferably when their head is extended to straighten the airway.
Finding no difference between the first and second group of patients, Brain realised that muscle relaxation was not required for insertion.
Finally, Dr Brain used the device in a dental extraction patient, he realised that because the space in and around the glottis was filled by the mask, the need for packing was much reduced and more impressively the larynx was completely protected from surgical debris.
Brain realised the exciting possibility that the laryngeal mask could be applied to head and neck surgery[5] and also observed that "In two patients the anatomy was such as to suggest that endotracheal intubation might have presented at least moderate difficulty.
Secondly, as no manual support of the jaw was necessary the hands of the anaesthetist were freed for monitoring, record keeping and other tasks.
The LMA Classic was launched in the UK and the British anaesthesia community were quick to realise the potential benefits of the laryngeal mask.
By 1992, the laryngeal mask was approved for sale and being sold in Australia, New Zealand, South Korea, Hong Kong, Taiwan, Malaysia, India and the United States.
The laryngeal mask revolutionised anaesthetic practice and by 1995 had been used in excess of 100 million patients and was available in more than 80 countries throughout the world.