LMA Insertion

We will now review LMA insertion technique. The overarching goal of insertion is to achieve and maintain a viable augmented airway, which permits adequate delivery of oxygen to the patient. This goal can be broken down into the following four key elements (4 Ps):

  • Provide unrestricted oxygenation and ventilation
  • Permit spontaneous or mechanical (positive pressure) ventilation
  • Pressures – achieve an adequate primary (laryngeal) and secondary (oesophageal) seal. Aim:
    • Oropharyngeal leak pressure > 20cm H2O
    • Oesophageal seal of 40-60cm H2O or one sufficient enough to prevent aspiration
    • Achieve both seals using an intracuff (inflation) pressure of ≤ 60cm H2O to avoid excessive compression of surrounding structures
  • Protect surrounding upper airway structures for LMA-induced trauma, in particular the teeth and posterior pharyngeal wall.