A Prospective, Randomized, Non-Blinded, Crossover Controlled Clinical Trial Evaluating the Efficacy of Face Mask Ventilation With 45 Degree Head Rotation in Anesthetized Obese (BMI ≥ 35) Adults

Mask ventilation is a foundation of airway management after the initial induction of anesthesia. It allows for adequate oxygenation of the patient to buy enough time for intubation, during which the patient is not ventilated. However, in some patients mask ventilation may be difficult - older than 55 years, heavier (BMI > 26 kg/m^2), with no teeth, having a beard or sleep apnea. Inadequate ventilation, if not corrected, can result in decreasing oxygen saturation to dangerous levels - which could lead to devastating complications. As a result, the efficacy of mask ventilation is of critical importance to patient safety after the induction of anesthesia.

A recent study proposed that mask ventilation could be improved simply by turning a patient's head. The study showed that rotating a patient's head to a 45 degree angle significantly improved mask ventilation when compared with the head placed in a neutral position. However, this study was done in patients with a BMI lass than 35. As such, the effects of head rotation on the efficacy of mask ventilation has not been studied in patients with a BMI of 35 and greater.

Obesity (BMI ≥ 30 kg/m^2) affects almost 40% of US adults and is one of the most prevalent health concerns in our society. It is a predictor of difficult mask ventilation because it is associated with increased upper airway obstruction, decreased airway patency, and decreased lung volumes such as functional residual capacity (FRC). If previous findings in regard to the effects of 45 degree head rotation on the efficacy of ventilation hold true in the obese patient, then this study will show that head rotation could be used as a simple way to improve the efficacy of mask ventilation for patients with a BMI of 35 and above.