Objective:To observe the clinical application of flexible endoscope assisted by general versus pillow-under-shoulder supine position in nasotracheal intubation of the patients with difficult airway, and to explore the influence of intubation position in the intubation effect.Methods: A total of 168 patients with difficult airway who underwent nasotracheal intubation and oromaxillofacial surgery under general anesthesia were randomly divided into general supine position (control group) and pillow-under-shoulder supine position (experimental group) with 84 cases in each group.The first-time and the total success rate of intubation, the intubation time, and the rate of direct glottis exposure of the patients in two groups were recorded.The mean arterial pressure(MAP), heart rate (HR), and complications of intubation of the patients in two groups before induction, before tracheal intubation, during intubation, 1 and 5 min after intubation, were also recorded.Results:The first-time success rate of intubation in experimental group (94.0 %, 79/84) was significantly higher than that in control group (71.4%, 60/84) (P<0.01);the total success rate of intubation (98.8%, 83/84) had no difference compared with control group (97.6 %, 82/84) (P>0.05);the intubation time (57 s±12 s) was significantly shorter than that in control group (146 s±29 s) (P<0.01);the rate of direct glottis exposure (47.6%, 40/84) when the flexible endoscope passed through the posterior nasal apertures was obviously higher than that in control group (15.5 %, 13/84) (P<0.01).The values of MAP and HR of the patients in two groups before and during intubation were decreased significantly compared with the baselines (P<0.01), and came back to the baselines 1 and 5 min after intubation (P>0.05).There were no significant differences in the MAP and HR between different time points (P>0.05).The incidence rates of complications including pharyngalgia, hoarseness and epistaxis had no differences between two groups (P>0.05).Conclusion: Flexible endoscope assisted by pillow-under-shoulder in nasotracheal intubation has a higher intubation success rate, shorter intubation time and it is a superior procedure for the patients with difficult airway.

Objective:To investigate the role and mechanism of molecular hydrogen in lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods:Balb/c male mice were randomly(random number) divided into control group, control+H 2, LPS and LPS+H 2 group with 6 mice in each group. The levels of malondialdehyde (MDA) and Fe 2+ in lung tissue were detected by kits. The lung tissue morphology was observed. The infiltration levels of F4/80 positive macrophages in lung tissue were detected by immunofluorescence staining. A549 cells were divided into control, control+H 2, erastin and erastin+H 2 group. The reactive oxygen species (ROS), malondialdehyde, (MDA), lactate dehydrogenase (GSH), number of cell death and lactate dehydrogenase (LDH) release in each group were detected by kits. Nrf2, GPX4, and HO-1mRNA were quantified by real-time PCR, the protein expression level of Nrf2 was detected by western blot, and the nuclear translocation level of Nrf2 was observed by immunofluorescence. The chi-square test was performed before the measurement data were counted. One-way analysis of variance was used to compare differences between multiple groups. Results:Compared with the control group, the histopathological damage was aggravated, and the levels of MDA, Fe 2+ significantly increased in the LPS group, and F4/80 positive immune cells infiltration significantly increased (all P<0.05). Compared with LPS group, the degree of lung injury in LPS+H 2 group significantly reduced (all P<0.05). In vitro experiments, compared with the control group, the ROS, MDA levels, number of cell death and LDH release significantly increased in erastin group (all P<0.05), while GSH, and GPX4 mRNA levels decreased (all P<0.05). HO-1mRNA and Nrf2 nuclear translocation levels increased (all P<0.05). Compared with erastin group, ROS, MDA levels, cell death number and LDH release decreased in earstin+H 2 group (all P<0.05). The levels of GSH, GPX4 mRNA, Nrf2 mRNA, HO-1 mRNA and Nrf2 nuclear translocation levels increased (all P<0.05). Conclusions:Molecular hydrogen attenuates LPS-induced ALI by promoting Nrf2 nuclear translocation to inhibit ferroptosis of alveolar epithelial cells.