Feb 20 2014

How a Robot is Helping Reduce Hospital-Borne Infections


What’s that cute blue thing shining its lights in the patient rooms and hallways of the National Institutes of Health’s (NIH) clinical center in Bethesda, Md.? A literal life saver.

Tru-D, a new robot now gainfully employed at the NIH, shoots beams of ultraviolet (UV) light. The rays kill a range of pathogens, including many of the bacterial strains—such as MRSA and C.diff—that have been linked to 90,000 health system deaths each year, according to the U.S. Centers for Disease Control and Prevention (CDC).

Manual disinfecting rids surfaces of about half of the bacteria in an area. Limitations of human cleaning squads include the probability they can miss a few—or many—spots and that disinfectants must remain wet on a surface for a full ten minutes to fully do their job and then be rinsed away. That time commitment is often very costly for hospitals that typically need to turn over patient rooms quickly. But incomplete disinfection can leave a lot of disease. MRSA, for example, can remain on surfaces for as long as nine months.

The UV light units work by disrupting the DNA structure of pathogens, which destroys some and makes others harmless.

Tru-D is just one of several UV light units on the market. It has been getting some attention recently both because of the NIH purchase and because it has some especially interesting features, including a cloud-computing system that lets it link up to health system records and automatically chart which rooms have been disinfected.

UV light doesn’t come cheap. Units, which come in different sizes that determine how wide a space they can disinfect simultaneously, can range from about $60,000 to $120,000. But hospitals also consider what they’re saving by making the purchase—such as new fines under the Affordable Care Act for some hospital readmissions before thirty days after a discharge. And some of those readmissions are for infections acquired during a hospital stay.

The units won’t displace the human cleaning staff, says Steve Streed, system director of Epidemiology/Infection Control at the Lee Memorial Health System in Fort Myers, Fla. and a member of the Association for Professionals in Infection Control and Epidemiology For example, the robots can’t rid spaces of blood and other substances humans leave behind.

UV units can disinfect a space in ten or twenty minutes. One limitation on their power and cleaning time is the wattage in hospitals. Units can be made more powerful but would blow out a hospital’s circuits. Streed says one company is working on a hybrid unit that would use both electricity and battery to amp up the wattage—and likely reduce the time needed—to disinfect hospital spaces.

Streed says recent studies have found that human disinfecting still leaves 50 percent of residual bacteria and UV light gets rid of 99 percent of what remains. Another disinfecting system, fogging rooms with hydrogen peroxide, gets rid of 99.9 percent, but takes more time since air ducts have to be closed before it use and then reopened afterwards. Either option gets rid of sufficient bacteria, says Streed. What remains is generally not in high enough levels to infect a patient.

The CDC is funding studies on UV light for disinfecting at Duke University and the University of North Carolina, with results expected at the end of the year.

>>Bonus Link: Read a CDC Vital Signs Report on Hospital Acquired Infections.

Tags: Hospital-acquired infections, Hospitals, Infectious disease