BackgroundAwake fiberoptic bronchoscopic tracheal intubation is usually regarded as an effective method in the management of predicted difficult airway. Hypoxia during awake nasal fiberoptic bronchoscopic intubation leads to discontinuation of the procedure, prolonged manipulation time and increased risk of severe complications. The main aim of the study was to test whether the novel endoscopic mask is helpful for hypoxia during the intubation.MethodsThis was a randomized, controlled, multi-center study. 55 patients were recruited, but one patient was lost to follow-up. Finally, 54 patients (19 man and 35 women) were analyzed. After entering the operating room, nasal catheter oxygen-providing was given in the control group, and the treatment group received endoscopic mask oxygen-providing, with a flow rate of 3 L/min, lasting into the end of the intubation. Primary outcomes included mean arterial pressure, heart rate, minimum pulse oxygen saturation and incidence of pulse oxygen saturation ≤ 90%. Secondary outcomes included number of intubation attempts and time to intubation. All outcomes were finally measured.ResultsMinimum pulse oxygen saturation during awake nasal fiberoptic bronchoscopic tracheal intubation was significantly higher in the endoscopic mask intubation group (91.7% ± 4.7%) than that the nasal catheter intubation group (87.6% ± 8.2%, P = 0.031. Furthermore, the incidence of pulse oxygen saturation ≤ 90% was significantly lower in the endoscopic mask intubation group (20.0%, 5/25) than that in the nasal catheter intubation group (51.7%, 15/29, P = 0.037). But mean arterial pressure of during intubation was significantly higher in the endoscopic mask group (100.0 ± 13.3 vs 90.3 ± 21.8, P = 0.049). In addition, there were no differences in the number of intubation attempts (P = 0.45) or time to intubation between the two groups (P = 0.38).ConclusionsThe endoscopic mask was safely used in awake fiberoptic bronchoscopic tracheal intubation, with advantages of stable blood pressure and potential prevention of desaturation. Beginners for the intubation procedure and patients at high risk of hypoxia could benefit from the use of the endoscopic mask.Trial registrationTrial registration: www.chictr.org.cn. Registration No.: ChiCTR-TRC-13004086. Date of Registration: 8th, Sep, 2013.