Comparison of Microbial Count on Various Surfaces in Operating Rooms at Different Times of the Day

The purpose of this study was to determine the degree of microbial contamination of surfaces in the operating room (OR) and to understand the relationship between time and location of contamination. Five OR surfaces were sampled at two time points on three consecutive Mondays and Thursdays. Each sample was cultured on a blood agar plate and introduced to a liquid nutrient broth. The most sterile surface was the OR lights with only one positive growth sample at each time. At both times, the most commonly contaminated surface was the staff keyboard. Coagulase-negative staphylococcus was the most common isolated species. Contamination rate of OR surfaces was not affected by time of day or day of the week. Simple cleaning and daily decontamination of staff keyboards can significantly reduce bacterial burdens and should be of primary importance to optimize OR sterility. (Journal of Surgical Orthopaedic Advances 27(4):281–285, 2018)
Key words: bacteria, contamination, operating room, time of day