title: Air sampling methods to evaluate microbial contamination in operating theatres: results of a comparative study in an orthopaedics department.
abstract: OBJECTIVE
  To evaluate the level of microbial contamination of air in operating theatres using active [i.e. surface air system (SAS)] and passive [i.e. index of microbial air contamination (IMA) and nitrocellulose membranes positioned near the wound] sampling systems.
  
  
  METHODS
  Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy.
  
  
  RESULTS
  During surgery, the mean bacterial loads recorded were 2232.9 colony-forming units (cfu)/m(2)/h with the IMA method, 123.2 cfu/m(3) with the SAS method and 2768.2 cfu/m(2)/h with the nitrocellulose membranes. Correlation was found between the results of the three methods. Staphylococcus aureus was detected in 12 of 60 operations (20%) with the membranes, five (8.3%) operations with the SAS method, and three operations (5%) with the IMA method.
  
  
  CONCLUSIONS
  Use of nitrocellulose membranes placed near a wound is a valid method for measuring the microbial contamination of air. This method was more sensitive than the IMA method and was not subject to any calibration bias, unlike active air monitoring systems.
authors.affiliation: Department of Biomedical Sciences and Human Oncology, Section of Hygiene, University of Bari Aldo Moro, Bari, Italy. c.napoli@igiene.uniba.it
authors.forename: C
authors.initials: C
authors.lastname: Napoli
authors.forename: S
authors.initials: S
authors.lastname: Tafuri
authors.forename: L
authors.initials: L
authors.lastname: Montenegro
authors.forename: M
authors.initials: M
authors.lastname: Cassano
authors.forename: A
authors.initials: A
authors.lastname: Notarnicola
authors.forename: S
authors.initials: S
authors.lastname: Lattarulo
authors.forename: M T
authors.initials: MT
authors.lastname: Montagna
authors.forename: B
authors.initials: B
authors.lastname: Moretti
mesh_terms: D000391:Air Microbiology; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D058491:Bacterial Load; D006785:Hospitals, University; D006801:Humans; D007558:Italy; D009873:Operating Rooms