Effectiveness of Various Chemical Disinfectants versus Cleaning Combined with Heat Disinfection on <i>Pseudomonas</i> Biofilm in Hemodialysis Machines

Abstract

The development of bacterial biofilms in the hydraulic circuit of hemodialysis machines is routinely prevented by frequent use of a variety of chemical and heat disinfection strategies. This study compared the effectiveness of several chemical disinfectants, commonly used either alone or in combination with a treatment regimen that involved cleaning plus heat disinfection using an in vitro Pseudomonas biofilm model. Effectiveness of these procedures was evaluated using total and viable biomass quantitation and polysaccharide and endotoxin determination. The chemical disinfection procedures were only partially successful in removing all biofilm components. Heat disinfection alone killed viable biofilm bacteria, but did not remove all the biomass components, including endotoxin. The combination of cleaning with citric acid followed by heat disinfection was the most effective in eliminating all biofilm components from the hydraulic circuit of the in vitro model.

Comparative testing of disinfectant efficacy on planktonic bacteria and bacterial biofilms using a new assay based on kinetic analysis of metabolic activity

“…Only the addition of ultrasonic exposure during disinfectant exposure increased the disinfectant effects to nearly full efficacy. These results underline similar findings in previous studies on the effects of ultrasound exposure as well as other mechanical treatments or heat exposure (Madge and Jensen 2002;Holmes et al 2004;Dong et al 2013).…”

“…These results underline similar findings in previous studies on the effects of ultrasound exposure as well as other mechanical treatments or heat exposure (Madge and Jensen ; Holmes et al . ; Dong et al . ).…”

Heat Inactivation Renders Sputum Safe and Preserves Mycobacterium tuberculosis RNA for Downstream Molecular Tests

“…Heat treatment is an established technique that has been used to decontaminate medical devices, ensure aseptic inoculation, and aid in therapeutic preparations (17,18). However, for M. tuberculosis, reports have shown that short slide flaming or drying on a hot block is insufficient to completely inactivate all bacilli (19,20).…”

Hospital disinfection: efficacy and safety issues

“…Another model simulated Pseudomonas aeruginosa biofilm formation in the silicone tubing used in hydraulics modules of haemodialysis machines [36 ]. Chemical removal of the biofilm using 3.3% citric acid followed by autoclaving was much more successful than other chemical treatments (sodium hypochlorite, hydrogen peroxide and peracetic acid, alone and in combination).…”

“…Some attempt to simulate use conditions and use relevant substrata [35,36 ], whereas some might be termed 'convenience models' [37 -39 ], which employ easily available, simple substrata such as glass or plastic. No standard methods exist for different applications.…”