title: [State of the art and scientific evidence on the role of unidirectional airflow ventilation systems in reducing surgical site infections].
abstract: The use of unidirectional airflow ventilation systems in operating rooms is frequently recommended for the prevention of Surgical Site Infections (SSI). However, scientific evidence is lacking to clearly support this technology which entails high investment costs and operating expenses, as compared with traditional ventilation systems. This sparse evidence is mainly related to the small number of interventions analyzed in each study and the difficulty to distinguish the effects of ventilation and other important confounding factors, such as antibiotic prophylaxis, special operating staff clothing and adoption of educational and training programs against SSI for the surgical personnel. The different behavior of the industrialized countries towards this issue, as it comes out analyzing the existing Rules and Guidelines concerning operating rooms ventilation, reflects a precautionary approach towards a technology which, until recently, has clearly demonstrated neither benefits nor limitations. In 2008, a relevant scientific study was published, reporting results from 63 departments of 55 German hospitals for a total of 99.230 surgical interventions, in which a standardized SSI surveillance was performed. Unexpectedly, the study concluded that unidirectional airflow ventilation showed no benefit and was even associated with a significantly higher risk for severe SSI, as compared with turbulent clean air. The present review collects updates from the scientific literature and national and international Rules and Guidelines concerning the use of unidirectional airflow ventilation systems in operating rooms, analyzing all aspects involved in this issue, from the debated efficacy of these systems in reducing the incidence of SSI to the "side effects" associated to their use, as the relevant costs and the reduction of the environmental comfort for the operators.
authors.affiliation: Dipartimento Clinico di Scienze Radiologiche e Istocitopatologiche, Sezione Tecnologie Biomediche, Università degli Studi di Bologna.
authors.forename: E
authors.initials: E
authors.lastname: Marcelli
authors.forename: P
authors.initials: P
authors.lastname: Cacciari
authors.forename: D
authors.initials: D
authors.lastname: Pedrini
authors.forename: L
authors.initials: L
authors.lastname: Cercenelli
authors.forename: R
authors.initials: R
authors.lastname: Giannoni
authors.forename: M
authors.initials: M
authors.lastname: Musaico
authors.forename: G
authors.initials: G
authors.lastname: Plicchi
mesh_terms: D000389:Air Conditioning / Q000379:methods* / Q000592:standards; D004780:Environment, Controlled; D019317:Evidence-Based Medicine; D006801:Humans; D017053:Infection Control / Q000379:methods / Q000592:standards*; D007558:Italy; D015337:Multicenter Studies as Topic; D009873:Operating Rooms / Q000592:standards*; D013530:Surgical Wound Infection / Q000209:etiology / Q000517:prevention & control*; D014691:Ventilation / Q000379:methods* / Q000592:standards