Comparison of neutral position versus Lateral Head Rotation on Gastric Insufflation during Facemask Ventilation in Adults undergoing General Anaesthesia: A Randomized Controlled Trial

Facemask ventilation is a fundamental airway management skill that is vital for ensuring adequate oxygenation and ventilation during resuscitation and the induction of general anaesthesia. Facemask ventilation in an obstructed airway requires peak inspiratory pressures between 25 to 30 cm H2O, which may cause gastric insufflation in 40-60 percentage of population. The resulting rise in intra-gastric pressure can result in complications such as regurgitation of gastric contents leading to aspiration pneumonia, postoperative nausea and vomiting, reduced lung compliance and cardiac output. Studies have shown that 45 degree lateral head rotation can be an effective alternative to the neutral position for enhancing mask ventilation when airway obstruction occurs. Lateral head rotation significantly enlarges the upper airway diameter in the neck, increases the cross-sectional area in the retroglossal region, and shifts soft tissue away from the submandibular space, thereby reducing upper airway obstruction. While previous studies have examined the effects of various levels of peak inspiratory pressure on gastric insufflation in the neutral head position, the influence of lateral head rotation on gastric insufflation has not yet been investigated. With this knowledge, we expect lateral head rotation to effectively relieve airway obstruction, reduce peak inspiratory pressures, and minimize gastric insufflation during facemask ventilation in apneic adults.