Comparison of Ventilation Quality by Anatomic or Nasal Mask after Induction of General Anesthesia in Patients with Body Mass Index of above 40 kg/m2

Background: Considering the importance of anesthesia in people who are very obese, and the need to take the necessary activities to minimize the complications during and after the operation in these patients, this study aimed to compare ventilation quality by anatomic or nasal mask after induction of general anesthesia in patients with body mass index (BMI) of above 40 kg/m2. Methods: In this randomized clinical trial study, 70 obese patients with a BMI of more than 40 kg/m2 who were candidates for surgery were selected and randomly divided into two groups of 35. The first group were ventilated with oral mask and 100% oxygen for three minutes, and in the second group, ventilation was performed through the nasal mask. The hemodynamic and ventilation parameters and complications during and after surgery were evaluated and compared between the two groups. Findings: Evaluation of hemodynamic parameters during and after surgery did not show any clinical difference between the two groups. However, nasal ventilation patients had better ventilation and oxygenation indexes. Conclusion: The results of our study showed that the use of nasal mask instead of oral mask have a more favorable ventilation end-tidal CO2 (ETCO2) and oxygenation (SpO2) in patients undergoing surgery, and the same hemodynamic stability after induction of anesthesia in very obese patients.