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Supraglottic airway (e.g. laryngeal mask airway [LMA], i-Gel)


What is a supraglottic airway?

  • A flexible plastic tube with inflatable circular opening on end which sits over top of larynx
    • Provides some aspiration protection but doesn’t fully secure the airway
    • Can only withstand a small amount of positive pressure ventilation
    • It is attached to ventilation machine which allows spontaneous ventilation ± low-level positive pressure ventilation supplementation during surgery, or attached to ventilation bag in respiratory arrest
  • Use: airway protection during anaesthetic for surgery (if no risk of aspiration and a muscle relaxant is not required); cardiac arrest; if there is an indication for endotracheal intubation but the provider is not trained or attempts failed
  • Size: usually size 5 for men, size 4 for women


How to insert an LMA

  • Equipment required for insertion:
    • Supraglottic airway
    • Syringe for cuff inflation
    • Water-soluble lubricating jelly
    • Monitoring: end-tidal CO2 monitor, pulse oximeter, blood pressure
    • Tape
    • Suction
    • Ventilation bag
    • Face mask
    • Oxygen supply
    • Medications in awake patient: hypnotic, analgesia


Video on how to insert an LMA (laryngeal mask airway)

  • Insertion technique for supraglottic airway:
    • Give sedative and analgesia if required
    • Deflate cuff using 20ml syringe
    • Lubricate outer cuff
    • Position patient
      • Neck flexed to 15˚, head extended on neck (i.e. chin anteriorly), no lateral deviation
    • From behind the patient, hold the tube like a pen and insert into the mouth, sliding the outer cuff along the palate
    • Push back over tongue until it reaches the posterior pharynx wall
    • Apply pressure to direct it backwards and downwards until it reaches the back of the hypopharynx
    • Inflate the cuff (LMA; 40ml for size 5, 30ml for size 4)
    • If required, attach ventilation bag/machine and ventilate (approx 10 breaths/min) with high concentration oxygen
    • Observe chest expansion and auscultate to confirm correct positioning
    • Consider applying CO2 detector or end-tidal CO2 monitor to confirm placement
    • Secure with bandage or tape


Other airway pages