after extubation(P<0.05).Conclusion：Patients with general anesthesia with tracheal intubation of the high rate of pulmonary infection，Acinetobacter Baumannii is the main pathogenic bacteria，to focus on monitoring the infection route，the time of tracheal intubation is difference，the routes of infection are different，the retrograde infection of the stomach-pharynx-lower respiratory tract is an important infection route for lung infection ......