Abstract:Objective To analyze the effect of conventional treatment combined with alveolar lavage in treatment of severe pneumonia.Method Computer retrieval of domestic databases such as CNKI, Wanfang Data, Baidu Scholar, and retrieval of PubMed foreign language database, collect related to severe pneumonia conventional treatment combined with alveolar lavage randomized controlled trials of clinical research, retrieval time limit for January 2019 to December 2021, the control group in the treatment of severe pneumonia conventional, the experimental group for conventional treatment combined with alveolar lavage (hereinafter referred to as the combination therapy). Two researchers evaluated the quality of research methods and extracted data of the included RCTS according to the Cochrane Collaboration Manual of Risk Assessment. RevMan 5.4 software was used for Meta-analysis.Result 21 literatures were included, including 1 735 patients, including 868 in the experimental group and 867 in the control group. The results of Meta-analysis showed: The overall effective rate of the experimental group was higher than that of the control group (OR^ = 0.16, 95%CI: 0.13~0.19, P = 0.000); Clinical symptoms: recovery time of fever (MD = -3.41, 95%CI: -3.67~-3.15, P = 0.000), crackles disappear time of the lungs (MD = -2.36, 95%CI: -2.70~-2.01, P = 0.000), cough disappearance time (MD = -2.56, 95%CI: -2.97~-2.15, P = 0.000); Length of hospital stay (MD = -4.38, 95%CI: -5.53~-3.23, P = 0.000); Blood gas analysis: partial pressure of oxygen (PO2) (MD = 6.74, 95%CI: 5.79~7.68, P = 0.000), partial pressure of carbon dioxide (PCO2) (MD = -8.84, 95%CI: -11.02~-6.66, P = 0.000), blood oxygen saturation (SO2) (MD = 5.85, 95%CI: 4.89~6.81, P = 0.000); Indicators of infection: PCT concentration (MD = -1.95, 95%CI: -2.96~-0.95, P = 0.000); CRP concentration (MD = -11.33, 95%CI: -19.68~-2.97, P = 0.008); WBC concentration (MD = -2.69, 95%CI: -3.27~-2.11, P = 0.000); IL-6 concentration (MD = -9.21, 95%CI: -11.03~-7.39, P = 0.000). The differences were statistically significant.Conclusion Compared with conventional treatment for severe pneumonia, the overall effective rate of combined treatment is higher than that of conventional treatment. The clinical symptoms, length of hospital stay, blood gas analysis, and infection indicators were greatly improved. However, there are still some inter-group Meta-analysis results with high heterogeneity, and the reliability of the results still need to be further explored.