The evidence is clear: to fully clean and disinfect the OR, manual cleaning alone just doesn't cut it. Despite your turnover team's best efforts to wipe and mop every inch of cart, counter, table and floor, studies show that up to half of all operating room surfaces will remain contaminated with pathogens — including multidrug-resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA) — when you wheel the next patient in. The shortcomings of manual cleaning have ushered in a new era of whole-room disinfection technology. Which whole-room system is right for your facility? Let's start by considering:

• Throughput/turnaround time. What is your average caseload? How quickly do you need an OR to be cleaned and disinfected? Do you aim for end-of-day, between-cases or continuous disinfection?

Personnel/staffing. Do you have staff available to oversee a technology that requires manual remote operation, room evacuation/sealing and device repositioning?

• Ergonomics/space. What distance must a device that you wheel from room to room cover? What are the entrance/exit dimensions through which you would need to maneuver a device? What is your storage capacity for a mobile device?

For continuous disinfection in both occupied and vacant spaces, consider upper room or shielded ceiling UV-C, visible light/high-intensity narrow-spectrum light and dry hydrogen peroxide systems.

• Ceiling UV-C. There are 2 primary categories of upper room UV-C systems. The most well-known are those that originally gained popularity for their efficacy in preventing tuberculosis transmission in the 1960s. These units are mounted to the upper walls or ceilings of a room in an effort to keep the UV-C beams above a room's occupants. Ventilated movement of air within the room brings infectious aerosols into the germicidal beam and delivers disinfected air back to the "breathing zone." Safety concerns, however, have limited the use of these systems as reports of irritation to eyes (photokeratinitis) and skin (photodermatitis) have demonstrated that human UV-C exposure is occurring below the upper room zone.

Newer ceiling UV-C systems have solved this exposure problem by drawing air into a ceiling-mounted unit with a shielded UV-C lamp inside. Air is drawn in through a filter, disinfected and blown out by an internal fan, helping to recirculate the disinfected air. These systems offer a novel way of treating contaminated air and improving air quality. Studies have shown their effectiveness against both bacteria and fungi in the air; however, the impact on surface contamination remains to be studied.

• Dry hydrogen peroxide (DHP). DHP has been used for decades by the military and agriculture industry for environmental disinfection, but has only recently been used in healthcare settings. DHP has the same biocidal potency against bacteria, viruses, fungi and sporoforms as hydrogen peroxide vapors and mists, but is able to achieve its biocidal effect at far more dilute concentrations because the hydrogen peroxide molecules don't have to compete with water molecules to attach to microorganisms. It's safe for human exposure and can be used continuously throughout the day. This means air and surface disinfection is occurring before, after and while a procedure is underway, and when an open instrument tray or surgical wound are vulnerable to the settling of contaminants.

You can place DHP systems in an existing HVAC system. Like hydrogen peroxide vapors and ozone, DHP can disinfect an entire room because air carries it to both high- and low-touch/center and remote surfaces. A recent study evaluating surface contamination of obscure, low-touch surfaces (those not likely to be addressed with manual cleaning) demonstrated a 93% reduction after just 7 days of DHP use and a 98% reduction at 30 days. This underscores the ability of DHP, much like hydrogen peroxide vapors, to achieve whole-room disinfection by reaching all surfaces within a space.

From an operational standpoint, DHP systems offer an advantage not only because they don't impact room turnover time — a critical factor for facilities with high caseloads — but also because, like upper room UV-C or visible light systems, they are truly automated and don't require staff to operate or oversee. They're also far less expensive than mobile UV-C or hydrogen peroxide vapor systems.

Drawback: DHP is less potent in the presence of water, so its efficacy is diminished on wet surfaces.

• Visible or high-intensity narrow-spectrum (HINS) light . The antimicrobial properties of visible light have been recognized for centuries and are thought to be the reason early hospital designs featured natural ventilation and exposure to sunlight. Because the most germicidal wavelengths of light fall in the UV spectrum (240nm to 260nm), healthcare facilities have been slow to adopt technologies using light in the visible spectrum. More recent research has shown, however, that systems generating narrow-spectrum light near the 405nm wavelength (which falls within the visible spectrum of 400nm to 700nm) inactivate a number of bacteria, including many common HAI-associated organisms. This inactivation appears to be species-dependent, though, with a general trend towards greater Gram-positive species susceptibility than Gram-negative species. Additionally, viruses are thought to have little susceptibility due to the mechanism of microbial inactivation.

Several studies over the past decade have shown effective reductions in environmental surface contamination in a number of healthcare settings, including one study that demonstrated use in the OR was associated with a concomitant reduction in periprosthetic joint SSIs — one of the costliest and devastating surgical site infections. To date, there have been no studies on air disinfection.

These ceiling-mounted systems contain a combination of violet and white light-emitting diodes (LED) to provide the necessary illumination. They are automated, and some are equipped with an occupancy sensor that lets the light switch to a higher and more germicidal dose of high-intensity narrow spectrum— or HINS — light when the room is unoccupied. Their ability to be used in an occupied space is a notable advantage over UV-C light. OSM