Strategies to prevent bacterial fallout and reduce particle count in the operating room (OR) are key components of preventing periprosthetic joint infection. Although OR traffic control is an important factor, a quantitative study has not been performed to investigate the influence of personnel and door opening on OR air quality. This simulated study aimed to examine the influence of these 2 factors on particle density in OR with and without the laminar air flow (LAF).
Both experiments took place within an empty OR of an arthroplasty unit equipped with an LAF system. First, the number of particles in the air was counted using a particle counting apparatus while 9 persons entered the room, one every 15 minutes. Second, the door was opened and closed starting with zero door openings per minute and increasing to 4 in 15-minute increments. Both experiments were performed once with the LAF turned on and once without.
The number of personnel in the OR and the number of door openings per minute correlate with the density of particles. Both relationships were significantly reduced by turning the LAF on (correlation coefficients <0.4). With the LAF being turned on, the particle density per person decreased from 211.19 to 18.19 particles/ft3 (P < .001) and the particle density per rate of door openings declined from 117.80 to 1.90 particles/ft3 (P = .017).
This study confirms that personnel and door opening are a major source of particles in the OR air. Controlling traffic is critical for reduction of particles and is likely to be a key preventative strategy in reducing periprosthetic joint infection. LAF is protective against the negative influence of number of people and door openings.