Do moisture exchangers prevent patient contamination of ventilators? A microbiological study comparing two different humidifying devices.
Fifteen tracheostomized and mechanically ventilated patients in an intensive care unit for surgical patients were studied. Two types of humidifiers were used: the Cascade humidifier and the Servo humidifier. Results from bacteriological cultures of the tracheal exudates, the expiratory and inspiratory ports of the ventilator, and various parts of the Servo humidifier are presented. There was a high incidence of colonization of the trachea of the patients. When the Cascade humidifier was used, a low rate of contamination in the expiratory and inspiratory ports of the ventilator was found, while no such contamination could be demonstrated with the Servo humidifier. There was a great difference in the colonization rate of the three different parts of the Servo humidifier. The part first exposed to the gas from the patient was frequently contaminated whereas the part towards the ventilator was not contaminated et all.
D001419:Bacteria / Q000302:isolation & purification*; D006801:Humans; D006813:Humidity; D013997:Time Factors; D014132:Trachea / Q000382:microbiology*; D012122:Ventilators, Mechanical