Clinical Trial Radar

Adequate Bag-Mask Ventilation

When an anesthetized patient is being manually ventilated by an anesthesia bag and a face mask and achieving a tidal volume of 5 ml/kg, it will be called adequate mask ventilation. * Easy if a single anesthesiologist achieves visible adequate chest rise and an end-tidal CO₂ graph. * Moderately difficult, if there is a slight chest rise, a low end-tidal CO₂ graph, but peripheral oxygen saturation is maintained above 97%. * Difficult if there is no visible chest rise, minimal or no end-tidal CO₂ graph, or if peripheral oxygen saturation drops to less than 95% but becomes normal with use of an oral airway (Guedel airway) or a laryngeal mask airway (LMA), or if two anesthesia providers are required for adequate mask ventilation. * Very difficult if peripheral oxygen saturation drops to 90% or less despite the use of airway adjuncts (Guedel airway or LMA).

Only once, after giving general anesthesia but before an endotracheal tube is put in the trachea

Difficult Tracheal Intubation

Difficult tracheal intubation will be defined as, one that requires external laryngeal manipulation, laryngoscopy requiring more than 3 attempts at intubation, intubation requiring nonstandard equipment or approaches, or the inability to intubate at all

Only once, after giving general anesthesia and 3-minute bag-mask ventilation for adequate muscle relaxation effect, then direct laryngoscopy will be performed to put the endotracheal tube in the trachea