Hydrogen Peroxide Vapor Helps Eradicate Hospital ‘Superbugs’
Johns Hopkins decontaminates isolation rooms with robotic, vapor-dispersing devices (Dec. 31)
Infection control experts at Johns Hopkins Hospital have found that a combination of robot-like devices that disperse a bleaching agent into the air and then detoxify the disinfecting chemical are highly effective at killing and preventing the spread of multidrug-resistant bacteria, or so-called hospital “superbugs.” Each of the paired hydrogen peroxide vaporizers is about the size of a washing machine and weighs nearly 60 pounds.
A report on the use of the devices — first deployed in several Singapore hospitals during the 2002 outbreak of severe acute respiratory syndrome (SARS) and later stocked by several U.S. government agencies in case of an anthrax attack — was published in Clinical Infectious Diseases.
In the study, the Johns Hopkins team placed the decontaminating units in single hospital rooms after routine cleaning to disperse a thin film of hydrogen peroxide across all exposed hospital equipment surfaces, as well as on room floors and walls. The enhanced cleaning reduced by 64% the number of patients who later became contaminated with any of the most common drug-resistant organisms. Moreover, the researchers found that protection from infection was conferred on patients regardless of whether the previous room occupant was infected with drug-resistant bacteria.
The researchers also noted that enhanced cleaning with the vapor reduced by 80% a patient’s chances of becoming colonized by a particularly aggressive and hard-to-treat bacterium, vancomycin-resistant enterococci (VRE).
Approximately 6,350 patient admissions to Johns Hopkins Hospital were closely tracked as part of the 2½-year analysis, as patients moved into and out of 180 private hospital rooms. Almost half of the rooms received enhanced cleaning with hydrogen peroxide vapor in between patients, while the rest did not. Overall, multidrug-resistant organisms were found on room surfaces in 21% of rooms tested, but mostly in rooms that did not undergo enhanced cleaning.
“Our study results are evidence that technological solutions, when combined with standard cleaning, can effectively and systematically decontaminate patients’ rooms and augment other behavioral practices, such as strict hospital staff compliance with hand-washing and bathing patients in disinfecting chlorhexidine when they are first admitted to the hospital,” said lead investigator Trish Perl-Delisle, MD, MSc.
After a room has been cleaned, the vents are covered and the two vaporizer devices are placed inside. The sliding door is closed, and the room is sealed. Then, the larger of the two devices disperses hydrogen peroxide into the room, leaving a thin, almost invisible layer (only 2 to 6 microns thick) on all exposed surfaces, including keyboards and monitors, as well as on tables and chairs.
Because hydrogen peroxide can be toxic if ingested or corrosive if left on the skin for too long, the second, smaller device is activated to break down the bleach into its component water and oxygen parts. The combined operation takes the devices about an hour and a half to complete.
Source: Johns Hopkins Hospital; December 31, 2012.