Supraglottic airway devices (SADs) have been widely used as an alternative to tracheal tubes in recent years. Haemodynamic response, postoperative sore throat, coughing, hoarseness, stridor, dysphagia and gagging are reduced in number with SADs compared to tracheal intubation [1]. SAD shortens emergence from anaesthesia and is widely used in elective surgeries and in difficult intubation [1]. SAD is quicker and easier to place than the tracheal tube and there is reduction in usage of neuromuscular blocking drugs [2] (see Fig. 1)

Some surgeries require a change in position of the head and neck for better visualisation of the operative field during surgery. SADs provide adequate ventilation in neutral head position. Some studies have shown that when head and neck position is changed, ventilation through the SAD gets affected. Changes in the head and neck position may result in changes in the shape of the pharynx. There is change in the force transmitted to the cuff along with the airway tube leading to change in the efficacy of the seal, ventilation and fiberoptic view [3]. Various studies have compared performance characteristics of multiple SADs in different head and neck positions [4].

Clinical importance of seal pressure is often overestimated. All devices exhibiting seal pressures over 25 cms of water should work well in clinical practice. On the other hand, the devices having seal pressures lower than 20 cm of water are not feasible for using in airway maintenance with controlled ventilation [5].

There is paucity of literature on comparing the second generation Supraglottic Airway Devices namely Proseal Laryngeal Mask (PLMA), i-gel and AuraGain with each other in different head and neck positions. We plan to compare the performance characteristics of Proseal Laryngeal Mask, i-gel and AuraGain in flexion, extension, neutral and left lateral rotation in adult patients undergoing elective surgery.