Mobile air-handling unit protects sterile surgical zone

A mobile platform that circulates air through a specially designed HEPA filtration system is used to direct a nonturbulent, ultra-clean air flow toward the procedure site and sterile instruments during ophthalmic surgery.

A mobile clean air zone unit (Operio Mobile, Toul Meditech AB) that eliminates airborne particulate matter around the operating table reduces the risk of infection during ophthalmic surgery, said Jack Wagner Sr., ScD, MPH.

“In 1973, Dr. William Whyte and colleagues observed: ‘Everything which is to come in contact with the wound has been made sterile except the air, which is in contact with everything.’

In a paper published in 2004, Persson and van der Linden colleagues stated: ‘An ultra-clean airflow from the ceiling downward may convey airborne particles from the surgical team into the wound, thus increasing the risk of infection. To protect a surgical wound against direct airborne contamination, air should be directed away from the wound rather than toward it.’,” said Dr. Wagner, director of scientific and technical services, Aseptic Air Control, Rolling Meadows, IL.

Focus on sterility

The mobile clean air zone unit ensures that the surgical site and instruments kept nearby on trays remain sterile during the entire surgical procedure, Dr. Wagner said. Although there has been a long history of interest in methods for surgical site infection control, and the importance of hand hygiene, instrument sterilization, and disinfection at the surgical site is constantly reinforced, the potential for transmission of infectious agents via airborne particulates is an issue that has not been adequately addressed, Dr. Wagner said.

“An individual emits and sheds about 10,000 skin cells per minute, and about 10% of those particles carry bacteria,” he noted. “Onethird of surgical site infections are caused by airborne particulate matter in the operating room, and not because of lapses in technique or adherence to surgical protocols.”

Air filtration systems that are conventionally used in hospital operating rooms are built into the ceiling and contain a high-efficiency particulate air (HEPA) filter that filters out particulate matter entering into the room from above.

By the time air reaches the surgical site, it has become contaminated by the particulate matter that is shed by personnel in the room, among other sources, he said. The mobile clean air zone is a rolling platform covered with a sterile protective barrier that allows it to be positioned near the procedure zone.

By circulating air through a specially designed HEPA filtration system, which filters 99.995% of particles down to >0.3 μm, the unit produces a nonturbulent, ultra-clean air flow that is aimed toward the procedure site and sterile instruments. “Results from a number of studies show that the unit produces an aseptic airflow and maintains a sterile air zone with <5 colony forming units/m³ at the surgical site,” Dr. Wagner said.

The unit also has an integrated, detachable instrument tray that can eliminate the need for a separate instrument table.

Disclosures:

Jack Wagner Sr., SCD, MPHE: jwagner249@comcast.net This article was adapted from Dr. Wagner’s presentation at the 2018 meeting of the American Society of Cataract and Refractive Surgery. Dr. Wagner has a fi nancial interest in the importation and licensing of the Operio Mobile unit in the United States. The Operio Mobile unit received 510(k) FDA clearance in 2016. It is distributed in the United States through Aseptic Air Control.