Study finds air purifiers do not reduce surgical infection risk

Published in Anesthesiology, the trial tested whether filtering airborne bacteria lowers infection risk. Researchers installed active air-purification systems (which filtered air and eliminated contaminants) in 34 of 68 operating rooms for four-week periods, while the other rooms received identical inactive units. Systems were switched after four weeks in a blinded design.

Surgical site infections affect roughly 1% to 3% of patients and remain a leading cause of postoperative illness, death, and readmissions. Daniel Sessler, MD, of UTHealth Houston, noted that while the bacteria responsible are known, their sources are not fully understood—and floating bacteria in the operating room had been one suspected contributor.

Results showed no difference in infection-related complications between active and inactive periods. The findings suggest airborne bacteria are not a major source of surgical site infections in modern operating rooms. “This tells us we should shift our focus elsewhere,” Sessler said, pointing instead to bacteria from a patient’s own skin or intestines and to infection prevention after surgery.

Future work should test air purification in less sterile settings such as hospital wards and ICUs, while the greatest gains may come from limiting direct wound contamination and refining surgical practices rather than adding more air-cleaning technology.

Other authors include Alparslan Turan, MD, of UTHealth Houston, along with colleagues from Cleveland Clinic and the Outcomes Research Consortium.

To read the full research article, click here (external link) or to see the UTHealth article click here (external link).

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