The value of polymerase chain reaction assay in ventilator-associated pneumonia in children undergoing congenital heart disease operation

Abstract

Objective To explore the value of polymerase chain reaction(PCR) to detect pathogens in ventilator-associated pneumonia(VAP) in children undergoing congenital heart disease(CHD) operation. Methods Forty-eight children selected from 95 cases with VAP underwent CHD operation were admitted in the department of CICU in our hospital from November 2016 to July 2017.Sputum specimens were separately collected by the bronchoalveolar lavage(BAL) and endotracheal tube attracts(ETA) methods, and the pathogens were detected by culture and PCR assay. Results Nineteen specimens were found to be positive after 72 h of culture.A total of 20 pathogens were detected and 2 samples were mixed infection(more than one pathogen), and the positive rate was 39.2%(19/48). For PCR assay, 44 pathogens from 31 samples were detected for just 24 h, 22 samples were single pathogen infection, 9 samples were mixed pathogen infection, and the positive rate was 65.3%(31/48). Compared with culture method, PCR assay could sharply increase the detection rate of every pathogen.Besides, the positive rate of the BAL or ETA for PCR assay was almost the same(45/48). Conclusion PCR assay for detecting pathogens is rapid, accurate and effective, which should be combined with culture method to detect for infectious pathogen.The ETA is the desired method to collect the sputum of the patients. Key words: Polymerase chain reaction; Congenital heart disease; Ventilator-associated pneumonia; Pathogens; Endotracheal tube attracts; Bronchoalveolar lavage