Abstract: Objective To observe the efficacy of edaravone combined with adaptive mechanical ventilation on chronic obstructive pulmonary disease(COPD) with type Ⅱ respiratory failure and their impact on serum clara cell secretory protein(CC16) and pulmonary activation-regulating chemokine(PARC/CCL18) and krebs von den lundgen-6(KL-6) .
Methods A total of 112 COPD patients with type Ⅱ respiratory failure were divided into observation group and control group according to random number method, each group had 56 cases. The control group were treated with adaptive mechanical ventilation, and the observation group was treated with edaravone on the basis of the control group. The efficacy, COPD assessment test(CAT) score, dyspnea, quality of life were observed in two groups after treatment,the forced vital capacity(FVC), peak expiratory flow(PEF), forced expiratory volume second(FEV1), maximum voluntary ventilation(MVV), partial pressure of oxygen(PaO2), partial pressure of carbon dioxide(PaCO2), oxygen saturation(SaO2), pH, CC16, PARC/CCL18 and KL-6 were observed in two groups before and after treatment. 
Results The total effective rate was 94.64% in the observation group, and 80.36% in the control group, the difference was statistically significant by rank sum test(Z=6206，P＜0.01). After treatment the quality of life, FVC, PEF, FEV1, MVV, PaO2, SaO2, pH and CC16were significantly increased compared with before treatment(P＜0.01), while the CAT score, dyspnea score, PaCO2, PARC/CCL18 and KL-6 was significantly lower than before treatment(P＜0.01), while the increasing or decreasing levels in the observation group were more obvious than those in the control group(P＜0.01). 
Conclusion Edaravone combined with adaptive mechanical ventilation has significant effects on COPD with respiratory failure, improving respiratory function and quality of life, correcting blood gas, and contributing to the repair of alveolar cells.

Key words: pulmonary disease, chronic obstructive, respiratory failure, krebs von den lundgen-6