Does the extended use of anaesthetic breathing circuits increase microbial contamination? A systematic review and...

Hospitals, and in particular operating theatres, contribute significantly to the carbon footprint of modern healthcare. Operating theatres account for a large part of hospital waste, which can be offset by using more reusable or recyclable equipment. However, environmentally sustainable decisions within healthcare need to be evaluated to ensure they can be introduced without a negative impact on patient safety or outcomes. We performed a systematic review and meta-analysis to evaluate the difference in the rates of microbiological contamination of anaesthetic breathing circuits between single day or extended (more than one day) use in the provision of general anaesthesia in adult patients, where a microbial filter was used and changed for each patient regardless of the duration of breathing circuit usage. The results demonstrate no significant increase in the rate of contamination between single day and extended use breathing circuits (odds ratio (OR): 0.84; 95% confidence interval (CI): 0.44 to 1.60) or single day and seven-day breathing circuits (OR: 1.30, 95% CI: 0.34 to 4.97). This supports the use of extended use breathing circuits for up to seven days for both the demonstrated environmental and financial benefits, with no evidence of compromise to patient safety.