Purpose: Difficult mask ventilation occurs due to the inability to form a seal between the patient’s face and the mask. The NuMask® is an intraoral mask with a flange that forms a seal against the buccal gum line. We aimed to compare the intraoral mask and conventional face mask for ventilation of the lungs of patients under general anesthesia. Methods: This randomized crossover study was conducted on 40 adults who were not anticipated to be difficult to mask ventilate. In Group CI, mask ventilation was done using a conventional face mask for 1 min and then an intraoral mask for 1 min. In Group IC, mask ventilation was done using an intraoral mask first and then a conventional face mask. An anesthesia ventilator was used to deliver pressure-controlled ventilation with a target pressure of 15 cm H2O and a respiratory rate of 10 bpm during mask ventilation. The primary outcome was expired minute volume obtained using both devices. Results: The expired minute volume using conventional face mask was 6328 ± 2509 mL in Group CI (Conventional Intraoral) and 6289 ± 1735 mL in Group IC (Intraoral Conventional) (p = 0.954). The expired minute volume using intraoral mask was 6154 ± 1905 mL in Group CI and 6501 ± 2013 mL in Group IC (p = 0.578). Overall, expired minute volume was comparable using conventional face mask and intraoral mask, i.e., 6308 ± 2129 and 6328 ± 1942 mL, respectively (p = 0.93). The end-tidal carbon dioxide during mask ventilation was also similar (p = 0.107). There was no trauma to face, lips, gums, or teeth in any patient. Conclusion: Both conventional face mask and intraoral mask were comparable for the ventilation of the lungs of patients without anticipated difficult mask ventilation under general anesthesia.
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