Placement of LMA Supreme versus GuardianCPV – a randomized controlled trial assessing leak pressure, cuff pressure and fibreoptic grading of airway placement.

INTERVENTION: Laryngeal Mask Airways (LMAs) are airway devices that are placed in the pharynx for the duration of an anaesthetic. The duration of anaesthetic differs on a case by case basis, as demanded by the surgical procedure. This is a one‐off treatment for a specified surgical procedure. The research project aims to compare 2 different LMA devices – one of which we use on a daily basis (the LMA Supreme), and the other is a newly released LMA (the GuardianCPV) which claims certain benefits. The guardianCPV claims to have a higher seal pressure. CONDITION: Laryngeal mask airway placement during surgery. PRIMARY OUTCOME: Cuff pressure ‐ the air pressure in the cuff of the airway device, measured by connecting a manometer to the cuff inflation valve. the fibreoptic grading ‐ an assessment of how well the LMA is placed, gained from visual inspection of the larynx through the LMA using a camera. An image of the larynx will be recorded and later graded according to an established fibreoptic grading system. the seal pressure ‐ the pressure in the lungs at which air begins to leak around the edges of the LMA, measured by occluding the airway valve, allowing airway pressures to slowly rise, and noting the pressure at which air leak is heard around the airway device SECONDARY OUTCOME: nil INCLUSION CRITERIA: Adult patients undergoing elective surgery with an LMA