RESUMEN
AIM: The necessity for routine disinfection of floors between two surgical procedures or disinfection only after visible contamination was assessed in two identical ophthalmological operating theatres equipped with laminar air flow ventilation. METHOD: Over a period of four weeks, one of the two tested operating rooms was disinfected after every surgical procedure, and the other only in the case of visible contamination. This regimen was inverted every week. To compare the air quality, particle count and total bacteria count were measured inside and outside the laminar air flow. Additionally, bacteria count was measured in the operating field, consisting of the operating table and the instrument tray. Patients were monitored for surgical site infection over a period of one year after operation. RESULTS: No difference in particle count or number of viable bacteria was found between the two investigated procedures. Also, no wound infections were observed after one year of surveillance for surgical site infection. CONCLUSION: It appears that frequent cleaning disinfection of floors is not necessary if a laminar air flow ventilation system is installed. Under these conditions, targeted disinfection of visibly soiled surfaces appears to be sufficient. Generally, the duration of surgical procedures should be kept as short as possible.