【摘要】 目的 探讨密闭式吸痰和开放式吸痰两种方式对预防心胸外科术后机械通气患者呼吸道感染的效果。 方法 2009年9月－2010年8月，将86例心胸外科术后机械通气患者随机分为两组，试验组应用密闭式吸痰法，对照组采用开放式吸痰法。观察两组患者术后机械通气治疗即刻及至拔出气管插管后48 h内每日痰培养结果、每4小时监测一次体温、血常规检查及胸片结果、呼吸机相关性肺炎（ventilator associated pneumonia，VAP）发生情况。 结果 两组患者在年龄、性别、病种方面差异均无统计学意义（Pgt;0.05），但痰培养结果阳性率、VAP发生率差异均有统计学意义（Plt;0.05）。两组发生VAP患者的痰培养病原菌检出情况:试验组均为G-菌；对照组以G-菌为主，余者为真菌-白色念珠菌。 结论 密闭式吸痰法预防心胸外科术后机械通气患者呼吸道感染效果较开放式吸痰法好。G-菌和真菌-白色念珠菌耐药性强，治疗难度大，临床中应重视呼吸道感染的预防。【Abstract】 Objective To evaluate the effects of closed endotracheal suctioning (CS) and open endotracheal suctioning (OS) on the prevention of respiratory tract infection in mechanically ventilated patients after cardiac surgery. Methods From September 2009 to August 2010, 86 mechanically ventilated patients after cardiac surgery were randomly divided into two groups. CS and OS were provided for patients in the experimental group and the control group, respectively. The sputum culture result, body temperature every four hours, blood routine examination and chest X-ray result, and the development of ventilator-associated pneumonia (VAP) were observed and compared between the two groups at the admission to the ICU and once a day thereafter. Results There were no significant differences between the two groups in sex, age, or kinds of diseases (Pgt;0.05). There were significant differences between the two groups in the positive rate of sputum culture results and the incidence of VAP (Plt;0.05). The pathogens isolation in sputum culture of VAP patients were all Gram-negative bacteria in the experimental group, and mainly Gram-negative bacteria followed by fungi-Blastomyces albicans in the control group. Conclusions CS is more effective than OS in the prevention of respiratory tract infection in mechanically ventilated patients after cardiac surgery. The drug resistance of Gram-negative bacteria and fungi-Blastomyces albicans is b, and the treatments of those bacteria are difficult. Thereafter, we should pay more attention to the prevention of respiratory tract infection.