Can particulate air sampling predict microbial load in operating theatres for arthroplasty?

Area of Science:

• Healthcare-associated infections
• Environmental monitoring
• Surgical site infection prevention

Background:

• Particle counting, adapted from cleanroom technology, is proposed for indirect evaluation of operating theatre air quality.
• A significant gap exists in demonstrating the correlation between particle counts and microbial sampling in surgical environments.

Purpose of the Study:

• To investigate the predictive value of particle counting for microbiological air contamination in an orthopedic operating theatre.
• To assess the relationship between particle counts (≥0.5 µm and ≥5 µm) and bacterial load during arthroplasty procedures.

Main Methods:

• Simultaneous active air sampling for bacterial contamination and particle counting (≥0.5 µm and ≥5 µm) during 95 arthroplasty surgeries.
• Data analysis comparing microbial loads and particle concentrations across different surgical procedures.

Main Results:

• No statistically significant correlation was found between particle counts and airborne microbial loads.
• Particulate concentrations (≥0.5 µm) were higher during knee replacements, while larger particles (≥5 µm) were higher during hip replacements.
• Mean bacterial load was 35 CFU/m³, mean particle count (≥0.5 µm) was 4,194,569/m³, and mean particle count (≥5 µm) was 13,519/m³.

Conclusions:

• Particle counting is not a reliable surrogate for microbiological air quality assessment in operating theatres.
• Microbiological monitoring remains the essential method for evaluating air quality in surgical settings to prevent infections.