Objective To observe the effect of civelestat sodium combined with low tidal volume lung protective ventilation on oxygenation level and inflammatory reaction in patients with acute respiratory distress syndrome(ARDS). Methods From January 2021 to March 2022, 96 patients with ARDS were selected from the Department of Critical Medicine of Hainan Cancer Hospital. They were divided into control group and observation group according to the method of random number table, with 48 patients in each group. The control group was treated with low tidal volume lung protective ventilation, while the observation group was treated with civelestat sodium combined with low tidal volume lung protective ventilation. Compare the mechanical ventilation, admission to ICU, hospitalization time, blood gas index(PaO₂), partial pressure of carbon dioxide(PaCO₂), oxygenation index(PaO₂/FiO₂), hemodynamic index(HR), mean arterial pressure(MAP), central venous pressure(CVP), pulmonary function index(FVC), forced expiratory volume(FEV₁), FEV₁/FVC) Inflammatory factors [interleukin-6(IL-6), C-reactive protein(CRP), white blood cell count(WBC)], and the incidence of adverse reactions. Results The time of mechanical ventilation, admission to ICU and hospitalization in the observation group was shorter than that in the control group(t/P=6.414/<0.001, 3.881/<0.001, 5.290/<0.001). At 24 and 72 hours after treatment, the PaO₂, PaO₂/FiO₂ in the observation group were higher than those in the control group, and PaCO₂ was lower than those in the control group(F/P=8.451/<0.001, 9.785/<0.001, 10.265/<0.001). At 24 hours and 72 hours after treatment, HR in the two groups showed a downward trend, while MAP and CVP showed an upward trend, and the observation group decreased/increased more significantly at the same time point(F/P=18.621/<0.001, 25.786/<0.001, 26.105/<0.001).The FVC, FEV₁, FEV₁/FVC in the observation group were higher than those in the control group 72 hours after treatment(t/P=5.971/<0.001、8.649/<0.001、10.404/<0.001). The levels of serum IL-6, CRP and WBC in the observation group were lower than those in the control group 72 hours after treatment(t/P=7.887/<0.001, 6.168/<0.001, .="" there="" was="" no="" significant="" difference="" in="" the="" incidence="" of="" adverse="" reactions="" between="" two="" p="">0.05). Conclusion Civelestat sodium combined with low tidal volume lung protective ventilation can improve the blood gas index of ARDS patients, stabilize hemodynamics, reduce lung injury and inflammatory reaction of the body, thus improving lung function, shortening mechanical ventilation, staying in ICU, and hospitalization time, and has high safety.

Acute respiratory distress syndrome;                    Civelestat sodium;                    Low tidal volume lung protective ventilation;                    Oxygenation level;                    Therapeutic effect;