Published in the September 2011 issue of Today’s Hospitalist
THERE’S A NEW WAY TO DISINFECT areas of the hospital that may be harboring organisms like C. diff and MRSA that requires no caustic cleaning chemicals. It instead uses a type of light that is remarkably effective at killing bugs.
The technology uses a form of ultraviolet (UV) light known as UVC. While UVA and UVB occur naturally in sunlight, UVC is a shorter-wave, higher-energy form of UV that is also germicidal. UVC penetrates the cell walls of microorganisms like C. diff and deactivates those cells so they can no longer replicate.
Hospitals are using UVC units produced by the Texas-based company Xenex (www.xenex.com) to clean operating rooms, ICUs and patient rooms. One hospital using the equipment found that its C. diff caseload dropped 82% after only a few months.
The portable units produce microbe-killing UVC light by pulsing xenon gas. Cleaning staff roll the unit, which is about the size of a vacuum cleaner, into a patient’s room, turn it on and leave. The machine then saturates the room with intense waves of UVC light, killing all microorganisms in their path.
Cleaning staff don’t stay in the room while it’s disinfected because long-term exposure to UVC light can cause cellular damage. But Mark Stibich, MD, Xenex’s chief scientific officer, says that UVC light waves can’t penetrate a closed door, so the technology is safe.
Dr. Stibich explains that the devices not only disinfect patient rooms up to 20 times more thoroughly than traditional cleaning techniques, but that they do so quickly. "Total room treatment time," he says, "is often under 10 minutes."
Using UV light was once common in TB wards, but the technology fell out of favor in part because of its cost. But with a new emphasis on preventing health care-associated infections, hospitals are suddenly interested in safe, proven technology. The cost of a Xenex device, the company points out, is less than treating one MRSA infection.
According to Dr. Stibich, the disinfection systems, which were released in June 2010, take the guesswork out of cleaning patient rooms. "There’s no chance for human error," he explains. "You know how much UV was in that room. It’s a systematic, automated approach." Hospitals that purchase the devices typically start by using them to clean the rooms of infected patients, then go on to target other areas like wards for immunocompromised patients and operating suites.
"We provide another layer of insurance and help hospitals make patients safer," Dr. Stibich says.