Air sampling methods to evaluate microbial contamination in operating theatres: results of a comparative study in an orthopaedics department

• Published in: The Journal of hospital infection Vol. 80; no. 2; pp. 128 - 132
• Main Authors: Napoli, C., Tafuri, S., Montenegro, L., Cassano, M., Notarnicola, A., Lattarulo, S., Montagna, M.T., Moretti, B.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2012; Elsevier
• Subjects: Air Microbiology; Air pollution; Air quality; Air sampling; Bacteria - classification; Bacteria - isolation & purification; Bacterial Load; Biological and medical sciences; comparative studies; Environmental microbial monitoring; General aspects; Hospitals; Hospitals, University; Human infectious diseases. Experimental studies and models; Humans; Infectious Disease; Infectious diseases; Italy; Medical sciences; Membranes; Microbial contamination; Operating Rooms; Operating theatre; Orthopaedics; Pollution monitoring; Staphylococcus aureus; surgery; Surgical site infection; Italy; Surgical site infection; Air quality; Environmental microbial monitoring; Operating theatre; Orthopaedics; Surgical wound; Nosocomial infection; Samplings; Air; Method; monitoring; Contamination; Surveillance; Environmental microbial; Operating room; Sampling; Comparative study; Public health
• ISSN: 0195-6701; 1532-2939; 1532-2939
• DOI: 10.1016/j.jhin.2011.10.011

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. Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy. 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. 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.