An original investigation in perioperative medicine, published ahead of print in the journal Anesthesiology, finds that air purification and sterilization systems may not be living up to their billing.
An article published by UTHealth Houston stated that the study of more than 110,000 surgeries found that “adding advanced air purification and sterilization systems to operating rooms did not reduce surgical site infections [SSIs], postoperative complications, or deaths.”
A selling point of air purification and sterilization systems for ORs is that airborne bacteria can contribute to SSIs, and that by using the systems to filter air in the OR, SSI risk can be reduced. The researchers tested that theory by installing two air-purification systems in each of 68 ORs for four weeks at a time over the course of several years. Half of the ORs received an active air-purification system that filtered air and eliminated bacteria and other contaminants, while the other half received “identical inactive units that looked and sounded the same,” according to the article. Every four weeks, the systems were switched, with patients and staff blind to whether the system was actually active at any given time.
The researchers “found no difference in infection-related complications between periods with active and inactive air-purification systems,” suggesting that “airborne bacteria may not be a major source of surgical site infections in modern operating rooms,” wrote UTHealth Houston.
While noting that the causes of SSIs are not well understood, the study “tells us we should shift our focus elsewhere,” said co-author Daniel Sessler, MD, professor and vice president for clinical and outcomes research at McGovern Medical School at UTHealth Houston in the article. “We are one step closer to identifying the factors that contribute most to these infections. Hospitals may benefit more from focusing on other possible sources, including bacteria from a patient’s own skin, bacteria from the intestines, or infection prevention after surgery.”
Dr. Sessler added that the greatest opportunity to reduce SSIs may come from “limiting direct wound contamination and improving surgical practices rather than adding additional air-cleaning technology.”
