Abstract
PURPOSE: The purpose of this study was to explore dynamic changes of respiratory microbiome in elderly patients undergoing prolonged mechanical ventilation (PMV) by isothermal microfluidic amplification chip technology (IAMC). METHODS: The study enrolled patients in six general hospitals in Beijing. Patients who developed Ventilator-associated pneumonia (VAP) within the observation period were enrolled in the VAP group, while those without VAP were categorized in non-VAP group. The study adopted IAMC technology to dynamically monitor the differences in the detection rates of bacteria, fungi, and viruses in the two groups. The conventional microbiological tests (CMT) were performed to clarify the correlation between KPC and drug resistance phenotype of K. pneumoniae. RESULTS: Among 218 patients, 78 were diagnosed with VAP. The pulmonary microbiota composition of patients without VAP was relatively stable. Compared with the non-VAP group, the detection rates of Enterococcus faecalis, Epstein-Barr virus, and Herpes simplex virus were significantly increased in the VAP group, whereas those of Haemophilus influenzae and Serratia marcescens were significantly reduced. In the VAP group, the detection rates of Enterococcus faecalis and Epstein-Barr virus were higher after the occurrence of VAP than before. A high correlation was observed between the KPC genotype of K. pneumoniae and its resistance phenotype. CONCLUSION: Viruses and Gut microbes might be closely related to the development of VAP in elderly undergoing PMV. The detection of the KPC gene of K. pneumoniae can guide antibiotic selection, and IAMC can aid in quickly identifying pathogens and facilitate targeted treatment. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2100051343.