Bioparticle concentration in operating room air: a comparison between two clothing systems of different source strengths

Background The permeability of surgical scrubs affects the bacterial load in the operating room (OR) air. Bacterial load can be measured by counting fluorescent bioparticles per unit of air. This study aimed to compare FBP≥3μm/50dm 3 (FBP) in air during primary arthroplasty surgeries using two different staff clothing systems. Methods The average FBP for 37 consecutive arthroplasty surgeries using reusable scrubs was compared to 37 surgery type-matched arthroplasties using single-use scrubs. An analysis of covariance (ANCOVA) was conducted to analyse the effects of surgery duration on log10 FBP while controlling for the number of staff present and surgery duration. Findings Mean FBP levels were 103 (95% CI [92,1 13] for the reusable scrubs and 18 (95% CI [16-21]) for the single-use scrubs. In the ANCOVA clothing type was strongly associated with log10-transformed FBP, accounting for 86% of the partial variance (η 2 = 0.86). In contrast, neither the number of staff nor surgery duration had a significant effect on FBP. Conclusion Clothing system permeability to bioparticles is one key factor in achieving air with low levels of bioparticles in OR air. Measuring FBP in real-time during arthroplasty surgery is a new possibility for studying the effect of distinct OR-related factors on air bacterial load.