Bacterial Filters???Are They Necessary on Anaesthetic Machines?

Contaminação do aparelho de anestesia por agentes patógenos

“…in a study to evaluate the efficacy of cleaning the anesthesia equipment to determine whether the use of bacterial filters is needed, three groups of patients, one with symptoms of respiratory tract disease, one with secretions in the respiratory tract, and the last one with chronic bronchitis, were evaluated 15 . out of 550 cultures performed before and after anesthesia only five cultures were positive for non-pathogenic bacteria, indicating that colonization of the equipment is low and it is controlled by adequate cleaning and sterilization after the use not justifying the use of bacterial filters in anesthesia equipment.…”

Evidence on measures for the prevention of ventilator-associated pneumonia

“…None presented a bacteriological demonstration of a cause-end-effect relationship; in addition, the study by TINNE et al [55] reported that the same isolate of Pseudomonas aeruginosa responsible for an outbreak of post-operative pneumonia was cultured from the corrugated tubing of the anaesthesia machine and from manual ventilation bags. Also, in some studies [57][58][59], after the sterilisation of the anaesthesia machine and the anaesthesia circuit, the intentional contamination of the expiratory circuit was not followed by the contamination of the anaesthesia machine.…”

History of Infection Control in Anaesthesia

“…Besides, one may suspect the likelihood of viruses being thus transmitted. 25 Generally, subsequent work has supported Magath's view and decontamination guidelines have been set out to prevent the theoretical chance of disease transmission [26][27][28][29][30][31] .…”

“…Ping et al considered the routine use of bacterial filters in the 38 operating rooms of the Vancouver General Hospital in 1979 but concluded: "The use of bacterial filters does not appear justified if a strict regimen of cleaning and pasteurisation is followed" 28 . Browne and Chernesky in 1988 thought 0.2 micron filters had a role in protecting "complex, difficult to sterilise equipment such as ventilators and soda lime absorbers from bacterial and viral contamination" 31 .…”