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Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management
Published on: November 21, 2017
Effectiveness of heating hospital sink drainpipes for reducing bacterial colonization
S Kakiuchi1, T Tanaka1, J Kawaguchi2
1Infection Control and Education Center, Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki City, Nagasaki, Japan.
Background:
Hospital sink drains act as reservoirs for nosocomial infection-causing bacteria. Drainpipe thermal disinfection units (DTDUs) inhibit or reduce bacterial colonization by elevating drainpipe temperature. However, their effectiveness remains to be comprehensively evaluated.
Aim:
This study investigated the effectiveness of a DTDU, in addition to routine cleaning and disinfection, in preventing bacterial colonization of new metal drainpipes in a clinical setting.
Methods:
This non-blinded parallel group comparative study was conducted in the intensive care unit of Nagasaki University Hospital, Japan. DTDUs were installed in three and five new sink drains for cleaning oral care (OC) devices and staff handwashing (HW), respectively. Two new sink drains without DTDUs for OC and HW were used as controls. Sinks were used as usual, with daily cleaning with ethanol-wipes and weekly flushing of a drain cleaner containing sodium hypochlorite. Additionally, OC drainpipes were disinfected using foam-type sodium hypochlorite. Samples were collected from insides of drainpipes biweekly for bacterial identification, semi-quantitative culturing, and antibiotic susceptibility test. The effect of the DTDUs on drainpipe bioburden was assessed using Fisher's exact test.
Findings:
Each sink was sampled 14 times. Bioburden was significantly lower in DTDU-equipped drainpipes than in controls for both OC devices and HW (both P < 0.01). Pseudomonas aeruginosa was the most frequently isolated bacterium (46.3%); however, it was not detected in DTDU-equipped OC drainpipes. Carbapenemase-producing Enterobacterales were detected in control HW drainpipes but not in DTDU-equipped HW drainpipes.
Conclusion:
Thermal disinfection of drainpipes may suppress bacterial colonization, including strains resistant to regular cleaning and disinfection.
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