The Effect of Laminar Air Flow and Door Openings on Operating Room Contamination

We evaluate the association of laminar airflow (LAF) and OR traffic with intraoperative contamination rates. Two sterile basins were placed in each room during 81 cases, one inside and one outside the LAF. One Replicate Organism Detection and Counting (RODAC) plate from each basin was sent for culture at successive 30-minute intervals from incision time until wound closure. At successive 30-minute intervals more plates were contaminated outside than inside the LAF. A negative binomial model showed that the bacteria colony forming units (CFU) depended on whether there were any door openings (P = 0.02) and the presence of LAF (P = 0.003). LAP decreases CPU by 36.6%. LAP independently reduces the risk of contamination and microbial counts for surgeries lasting 90 minutes or less. (C) 2013 Elsevier Inc. All rights reserved.