Study: Bacterial transmission in anesthesia work area increases SSI risk

Editor's Note

Recent research delved into the connection between the transmission of antibiotic-resistant bacteria in the anesthesia work area and the occurrence of surgical site infections (SSIs), Anesthesiology News July 19 reports. While it was previously recognized that reducing microbial transmission through the anesthesia work area is crucial for preventing SSIs, this study aimed to unravel the mechanics of how bacterial transmission translates into infections.

Led by Randy Loftus, MD, associate professor of anesthesia at the University of Iowa, the study retrospectively analyzed Staphylococcus aureus (S. aureus) isolates from prior samples and focused on factors such as the administered prophylactic antibiotic, transmission occurrences, and subsequent infection development. Titled “Transmission of Staphylococcus aureus in the anesthesia work area has greater risk of association with development of surgical site infection when resistant to the prophylactic antibiotic administered for surgery,” it was first published in the Journal of Hospital Infection in April 2023.

Key findings include:

• S. aureus transmission happened in 20% of cases, with 20% of those being resistant to the administered prophylactic antibiotic.
• Patients faced an 11% risk of SSI with transmission of antibiotic-susceptible S. aureus and an 18% risk with transmission of resistant S. aureus.
• Patients without S. aureus transmission had a 2% lower risk of SSI.
• The odds of an SSI increased by 3.59 with each unit increase in transmission events.
• Researchers identified 14 "transmission stories" linked to intraoperative reservoirs, predominantly the anesthesia machine, anesthesia personnel, or the patient.

The study highlights the critical importance of preventing bacterial transmission to curb SSIs and recommends adherence to infection control practices, including thorough decontamination procedures, hand antisepsis, and environmental cleaning. Preventing the transmission of isolates, whether sensitive or resistant to prophylactic antibiotics, should be the overarching goal to reduce SSI risks effectively.