We investigated how humidified high-flow nasal cannula oxygen therapy (HFNC) with a pulmonary infection control (PIC) window as a ventilation switching indication in combination with atomizing inhalation of terbutaline affects the lung function of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We examined 140 hospitalized AECOPD patients randomized to control and observation groups. Conventional supportive therapy and invasive mechanical ventilation with tracheal intubation were conducted in both groups, with a PIC window as the indication for ventilation switching. Noninvasive positive pressure ventilation (NIPPV) plus atomizing inhalation of terbutaline was used in the control group. In the observation group, HFNC combined with atomizing inhalation of terbutaline was used. Compared to the control group, after 48-hr treatment and treatment completion, the observation group had significantly increased levels of lung function indicators (maximal voluntary ventilation [MVV] plus forced vital capacity [FVC], p<0.05) and oxygen metabolism indicators (arterial oxygen partial pressure [PaO2], arterial oxygen content [CaO2], and oxygenation index, p<0.05). The comparison of the groups revealed that the levels of airway remodeling indicators (matrix metalloproteinase-2 [MMP-2], tissue inhibitor of metalloproteinase 2 [TIMP-2] plus MMP-9) and inflammatory indicators (interferon gamma [IFN-γ] together with interleukin-17 [IL-17], IL-10 and IL-4) were significantly lower after 48 h of treatment as well as after treatment completion (both p<0.05). These results demonstrate that HFNC with a PIC window as the indication for ventilation switching combined with atomizing inhalation of terbutaline can relieve the disorder of oxygen metabolism and correct airway hyper-reactivity.