title: Transmission of Mycobacterium chimaera from Heater-Cooler Units during Cardiac Surgery despite an Ultraclean Air Ventilation System.
abstract: Heater-cooler units (HCUs) were recently identified as a source of Mycobacterium chimaera causing surgical site infections. We investigated transmission of this bacterium from HCUs to the surgical field by using a thermic anemometer and particle counter, videotape of an operating room equipped with an ultraclean laminar airflow ventilation system, and bacterial culture sedimentation plates in a nonventilated room. Smoke from the HCU reached the surgical field in 23 s by merging with ultraclean air. The HCU produced on average 5.2, 139, and 14.8 particles/min in the surgical field at positions Off, On/oriented toward, and On/oriented away, respectively. Culture plates were positive for M. chimaera <5 m from the HCU in the test room. These experiments confirm airborne transmission of M. chimaera aerosols from a contaminated HCU to an open surgical field despite ultraclean air ventilation. Efforts to mitigate infectious risks during surgery should consider contamination from water sources and airflow-generating devices.
authors.forename: Rami
authors.initials: R
authors.lastname: Sommerstein
authors.forename: Christian
authors.initials: C
authors.lastname: Rüegg
authors.forename: Philipp
authors.initials: P
authors.lastname: Kohler
authors.forename: Guido
authors.initials: G
authors.lastname: Bloemberg
authors.forename: Stefan P
authors.initials: SP
authors.lastname: Kuster
authors.forename: Hugo
authors.initials: H
authors.lastname: Sax
mesh_terms: D058491:Bacterial Load; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D003428:Cross Infection / Q000175:diagnosis / Q000382:microbiology / Q000635:transmission; D004866:Equipment Contamination; D006801:Humans; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis / Q000382:microbiology* / Q000635:transmission*; D015269:Mycobacterium avium Complex; D011183:Postoperative Complications
keywords: Mycobacterium chimaera; aerosols; airborne transmission pathway; bacteria; cardiac surgical procedures; cross infection; disease outbreaks; heater–cooler units; nontuberculous mycobacteria; surgical wound infection; tuberculosis and other mycobacteria