Results The nosocomial infection was caused by Pseudomonas aeruginosa serotype ⅵ, and the main epidemic factors were due to the insufficient oxygen humidifier and aerosolizer and non-strict sterilization, infection was controlled after preventive measures were adopted. 结果本次医院感染暴发由PA血清Ⅳ型引起,其主要流行因素是所使用的氧气湿化瓶、雾化器数量不足,消毒不严。采取相应措施后感染得以控制。