Supraglottic airway devices (SAD) have revolutionised the field of airway management. These devices are above the glottis or the larynx and are also known as extraglottic devices. The first such device, the classic laryngeal mask airway (cLMA) was invented by Dr Archie Brain and introduced into clinical practise in 1988. It was followed by the introduction of several supraglottic devices in later years. ProSeal LMA, LMA Supreme, Ambu laryngeal mask, i-gel, Laryngeal Tube Suction (LTS), the intubating LMA (ILMA), oesophageo-tracheal combitube and cobra perilaryngel airway are a few of the popular supraglottic devices in use. Ambu Aura Gain is a new such device introduced in 2014.

These airway devices form a niche between a facemask and a tracheal tube.The last 30 years have witnessed increasing use and the widening scope of the SADs right from prehospital care,remote locations to operation theatres and cardiopulmonary resuscitation.This popularity stems directly from their ease of use,simplicity of training,predictability and speed of insertion.

Supraglottic airway devices have been classified in many ways depending on;a)whether they are reusable or disposable b)sealing mechanism c) ability to protect against aspiration d) direct endotracheal intubation facilitation.White et al described the first generation  supraglottic device as a simple airway tube.The second generation device has a larger cuff with dorsal and ventral components to provide a higher oropharyngeal seal pressure (OSP) than earlier options and a drain tube for gastric decompression,which may significantly decrease the risk of pulmonary aspiration during the course of anaesthesia. Miller developed a classification for supraglottic airways based on sealing mechanism. They can be cuffed perilaryngeal sealers, cuffed pharyngeal sealers and cuffless anatomically preshaped sealers. They can also be classified depending on the feasibility of straight forward intubation through them. The latter have also been labelled as third generation SADs.

The most recently introduced Ambu Aura Gain is a single use, disposable, cuffed perilaryngeal sealer. It is made up of polyvinyl chloride (PVC) which is phthalate free. The phthalates are known to alter the endocrine system, interfere with steroid genesis and interfere with luteal function in females. Phthalates also act as anti androgenic. The Ambu Aura Gain also facilitates insertion of large size tracheal tube as the airway tube is wider and there are no epiglottic bars.

In this study, we are comparing ProSeal LMA, Ambu Aura Gain and LMA Supreme, all of which provide higher OSP than the cLMA or an Ambu mask. In addition to the airway tube, a drain tube is also present for gastric access in all of the three above stated LMa variants.