[Comparison of safe duration of apnea and intubation time in face mask ventilation with air versus 100% oxygen during induction of general anesthesia].

Objective: To compare the safe duration of apnea and intubation time between face mask ventilation with air and 100% oxygen during induction of general anesthesia.

Methods: Eighty adult patients with ASA class I or II without predicted difficult airways were scheduled for elective surgery under general anesthesia. The patients were randomized to receive anesthesia induction with preoxygenation [Group 1, n=40, fraction of inspired oxygen (FiO)=1] or without preoxygenation (Group2, n=40, FiO=0.