Assessing a Novel Method to Reduce Anesthesia Machine Contamination: A Prospective, Observational Trial

Figure 3

The global density and diversity of CFUs across time. (a) Density of CFUs. (b) Diversity of CFUs. (a) presents a schematic depiction of the density (quantity), and (b) presents a depiction of the diversity (phenotypically distinct) of CFUs across time. Each line represents cases in a particular OR. The blue lines depict cases in which the anesthesia machine was covered with the AMW, and the red lines depict cases where an AMW was not employed. In cases where the AMW was used, there was a decrease or plateauing of the density of CFUs, while in those cases without the AMW there was general increase in the density of CFUs. Relatedly, in cases without the AMW, additional, phenotypically distinct species were added to the anesthesia machine, suggesting ongoing contamination with the anesthesia provider as vector. Note that in cases where the AMW was used, there tended to be a reduction or stabilization in bacterial species, with one exception, which suggests contamination possibly during the cleaning or machine preparation. CFUs = colony forming units; AMW = anesthesia machine wrap.

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