Abstract: Objective: To investigate the effects of oxygen inhalation by nasal catheter with medium and low flow（<4 L/min）in
routine humidification and non-humidification on the efficacy, comfort and cost of oxygen therapy. Methods: A total of 1 660 adult
inpatients were included with medium and low flow oxygen inhalation from July to November 2018 in two third-grade class-A hospitals
in Dali. They were randomly divided into the observation group and the control group. Non-humidification oxygen was used in the
observation group and humidification oxygen was used in the control group. The differences of oxygen therapy between the two groups
were compared. Results: After testing, there was no significant difference in the nasal mucosal hemorrhage, nasal mucosa dryness and
blood oxygen saturation between the two oxygenation methods（P>0.05）; the difference in the impact on the patient′s sleep was
statistically significant（P<0.001）. At the same time, non-humidified oxygen absorption reduced the cost of human and material
resources and improved the quality of patient′s sleep at night. Conclusion: Adult nasal catheter oxygen inhalation with medium and
low flow does not need to be humidified.

Key words: adult, medium and low flow, nasal catheter oxygen inhalation, non-humidification, humidification