Objective: To analyze the distribution and drug resistance of gram-negative bacteria detected in ICU, and to guide the rational use of antibiotics in clinic. Methods: The distribution and drug sensitivity of Gram-negative bacteria detected by comprehensive ICU in a tertiary hospital from July 2019 to June 2020 were retrospectively analyzed, and compared with the results of bacterial surveillance in CHINET tertiary hospital in 2019. Results: 598 strains of Gram-negative bacteria were isolated, mainly Enterobacteriaceae, and the detection rate of Klebsiella pneumoniae increased gradually. The top 7 bacteria were Klebsiella pneumoniae (24.92%), Acinetobacter baumannii (21.07%), Pseudomonas aeruginosa (18.90%), Escherichia coli (11.37%), Serratia marcescens (5.02%), Burkholderia cepacia (4.85%) and Proteus mirabilis (4.51%). The specimen was mainly collected from sputum (73.75%). The drug sensitivity results showed that the drug resistance rate of Escherichia coli and Klebsiella pneumoniae was higher than that of the CHINET tertiary hospital in 2019. The detection rate of multiple drug resistant bacteria was 81.27%, in which the highest detection rate of multiple drug resistance of Burkholderia cepacia was 100%, and the lowest detection rate of multiple drug resistance of Klebsiella pneumoniae was 73.15%. Amikacin has good antibacterial activity against common bacteria. Conclusion: Enterobacteriaceae is the most common pathogen of ICU, among which Klebsiella pneumoniae is the most common. The drug resistance rate of Enterobacteriaceae bacteria in this hospital is significantly higher than that in the CHINET tertiary hospital in 2019, and the detection rate of multiple drug-resistant bacteria is higher, which requires to standardize the use of antibiotics and strengthen the monitoring of bacterial drug resistance.
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