Comparison between mixed and laminar airflow systems in operating rooms and the influence of human factors: experiences from a Swedish orthopedic center.
BACKGROUND
The importance of laminar airflow systems in operating rooms as protection from surgical site infections has been questioned. The aim of our study was to explore the differences in air contamination rates between displacement ventilation and laminar airflow systems during planned and acute orthopedic implant surgery. A second aim was to compare the influence of the number of people present, the reasons for traffic flow, and the door-opening rates between the 2 systems.


METHODS
Active air sampling and observations were made during 63 orthopedic implant operations.


RESULTS
The laminar airflow system resulted in a reduction of 89% in colony forming units in comparison with the displacement system (P < .001). The air samples taken in the preparation rooms showed high levels of bacterial growth (≈ 40 CFU/m(3)).


CONCLUSIONS
Our study shows that laminar airflow-ventilated operating rooms offer high-quality air during surgery, with very low levels of colony forming units close to the surgical wound. The continuous maintenance of laminar air flow and other technical systems are crucial, because minor failures in complex systems like those in operating rooms can result in a detrimental effect on air quality and jeopardize the safety of patients. The technical ventilation solutions are important, but they do not guarantee clean air, because many other factors, such as the organization of the work and staff behavior, influence air cleanliness.
The Sahlgrenska Academy, Institute of Health and Care Sciences, University of Gothenburg, Gothenburg, Sweden; Department of Anesthesia, Surgery, and Intensive Care, Sahlgrenska University Hospital/Östra, Gothenburg, Sweden. Electronic address: annette.erichsen@vgregion.se.
Annette
A
Erichsen Andersson
Akademistatistik - Centre for Applied Biostatistics, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Max
M
Petzold
School of Life Sciences, University of Skövde, Skövde, Sweden.
Ingrid
I
Bergh
Department of Orthopedics, Sahlgrenska University Hospital, Gothenburg, Sweden; The Sahlgrenska Academy, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden.
Jón
J
Karlsson
Department of Orthopedics, Sahlgrenska University Hospital, Gothenburg, Sweden; The Sahlgrenska Academy, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden.
Bengt I
BI
Eriksson
The Sahlgrenska Academy, Institute of Health and Care Sciences, University of Gothenburg, Gothenburg, Sweden.
Kerstin
K
Nilsson
D000391:Air Microbiology; D000392:Air Movements; D016902:Air Pollution, Indoor / Q000517:prevention & control; D001178:Arthroplasty; D015169:Colony Count, Microbial; D004784:Environmental Monitoring; D006784:Hospitals, Teaching; D006801:Humans; D009873:Operating Rooms; D009985:Orthopedics; D013530:Surgical Wound Infection / Q000517:prevention & control*; D013548:Sweden; D014691:Ventilation / Q000379:methods*
Air sampling; Door openings; Infection control