Effect of Continuous Supraglottic Oxygen Insufflation Via Video Laryngoscope Blade on Apneic Oxygenation During Tracheal Intubation Under General Anesthesia

Before surgery, all participants received a radial arterial line. At arrival to the operating theatre, ECG, invasive arterial blood pressure, pulse oximetry, and train-of-four monitoring were applied. An i.v. line was secured, and a standard infusion of electrolyte solution was started. Participants were then placed supine, in a 10 degrees reverse Trendelenburg position. Preoxygenation was then perform using atight fitting face mask and having each subject breathe 100% O2 at 15 L/min.Tracheal intubation was thereafter performed using a video laryngoscope when the anaesthetist assessed the conditions as appropriate in the control group (Group C).The correct placement of the tracheal tube was confirmed visually by the anaesthetist in charge and a member of the study team. The tracheal tube was secured, and the participant was left apnoeic with the tracheal tube open to the atmosphere until the peripheral oxygen saturation declined to 93% or apnoea is sustained for 5 minutes.