DOS 2018

262 · DOS Abstracts Incidence of early periprosthetic joint infection and influence of air quality following commissioning of a new operating room. Kappel Andreas, Nielsen Jeanette Gade, Stengaard-Pedersen Henrik, Valsted Inge-Merethe, Christensen Poul Hedevang, Simonsen Ole Højgaard Orthopedics Aalborg/Farsø, Aalborg University Hospital; , Aalborg University Hospital; Orthopedics Farsø, Aalborg University Hospital Background: Air quality in operating rooms (OR) used for joint replacement surgery should be “ultra-clean” and a maximum of 10 colony forming units/m3 (CFU) is guided. Purpose / Aim of Study: To draw attention to the accumulation of early peri- prosthetic joint infection (PJI) and the coincidence of elevated CFU count in a newly commissioned OR. Materials and Methods: Primary knee replacement at Farsø Hospital in the period from 2013 to 2017 were reviewed, re-operation within 8 weeks, were identified. Details regarding the commissioning and monitoring of the OR were collected. Findings / Results: 19 re-operations within 8 weeks and 1982 primary knee arthroplasties were identified. 14 cases were early PJI (within 4 weeks) and 5 cases were other causes (2 “late” infections, 1 fracture, 1 patella dislocation, 1 patella ligament avulsion). Mean rate of early PJI was 0.2 cases per month cor- responding to an incidence of 0.7%. In 2017 4 cases presented with early PJI within 4 weeks. Auditing revealed the only common characteristic to be surgery in the newly commissioned operating room. The OR had been used 2 weeks before the first early PJI case was operated, another technical identical room with had been used for 30 months without PJI being observed, both new rooms have turbulent air flow (TAF). OR air quality was monitored and CFU of 36 was measured in the new OR, in the identical room the CFU was 2.5. Following both cleaning and adjustments acceptable CFU counts were obtained, however CFU count are monitored monthly and remain to fluctuate between 0.8 and 8.3. No further PJI cases have been identified. Conversion of the TAF rooms to laminar flow is planned. Conclusions: OR’s with identical technical specifications can have different air quality. Especially when commissioning OR’s surgeons must advocate and insist that air quality is monitored continuously. 203.