Abstract

ARAI, Luiza Alves de Castro  and  AZEVEDO, Ricardo Bentes. Contamination of anesthesia circuits by pathogens. Rev. Bras. Anestesiol. [online]. 2011, vol.61, n.1, pp. 54-59. ISSN 0034-7094.  http://dx.doi.org/10.1590/S0034-70942011000100006.

BACKGROUND AND OBJECTIVES: Evaluation of contamination of anesthesia circuits by collecting 56 culture samples from the circular system; previously reprocessed tracheas by disinfection with 1% hypochlorite or 2% glutaraldehyde after being washed in non-sterile water and soap and dried by using compressed air and stored in surgical grade paper; and from other places of the non-reprocessed respiratory circuit, before anesthetic procedures. METHODS: Samples from the inspiratory and expiratory branches of the tracheas, canister, soda-lime, and collector jar (drain) through swab in Stuart medium and streaked in Agar blood, Mac Conkey, and Sabouraud growth media. RESULTS: The level of contamination with fungus and bacteria in the inspiratory and expiratory branches of tracheas reached up to 39.3% in some sites; in some cases, more than one microorganism was present, 75% fungal and 25% bacterial contamination. Cultures were positive for Candida sp., Dermatophytus sp., Penicillium sp., Aspergillus sp., Staphylococcus aureus, Staphylococcus saprophyticus, and Staphylococcus epider midis. Contamination was observed in 25% of the canisters with growth of Candida sp., Penicillium sp., Dermatophytus sp., Aspergillus sp., and Fusarium sp. In the collector jar, a contamination rate of 36% was observed with growth of Candida sp., Dermatophytus sp., S. saprophyticus and Acinetobacter baumannii. Microorganisms did not grow in soda-lime cultures. CONCLUSIONS: In all sites investigated except for soda-lime growth of microorganisms was observed with the possibility of cross infection.

Keywords : Equipment Contamination; Anesthesia, Closed-Circuit; Ventilators, Mechanical; Cross Infection.