Environmental sustainability in the operating room

BACKGROUND The healthcare industry carbon footprint is 5.2% of total CO2 equivalent emissions worldwide. The operating rooms are the most resource demanding areas in hospital care and the higher energy demands, lack of effective waste management, and inhaled anaesthetic use, lead to a high carbon footprint. There is wide variation in the carbon footprint of inhaled gases, with desflurane ranking 40 times higher than sevoflurane. Other inhaled agents, including N2O and isoflurane, have additional ozone-depleting properties. OBJECTIVE To describe what factors influence the implementation of sustainable anaesthetic strategies. DESIGN An international survey. SETTING Anaesthesia clinicians worldwide between April 2021 and April 2022. PARTICIPANTS One thousand two hundred and thirty-seven anaesthesia clinicians from 75 countries. MAIN OUTCOME MEASURES The primary outcome was a determination of the most used anaesthetic plans among anaesthesia practitioners. Secondary outcomes included an assessment of the influence of various socioeconomic variables on anaesthetic decision-making, and on the level of the practitioners’ awareness of peri-operative environmental sustainability. RESULTS Sixty-four percent of respondents use inhaled anaesthetics on a daily basis, with 83% preferring sevoflurane, and only 5% using N2O regularly. Forty-five percent do not know which halogen gas has the highest carbon footprint. Fifty-one percent do not use low flow anaesthesia regimes (<1.0 l min-1) due to concerns about CO2 rebreathing (30%), hypoxia (25%), compound A related renal failure (12%) or CO generation (10%). Only 15% use minimal flow anaesthesia (<0.5 l min-1). There is a correlation between higher income countries and implementation of more sustainable strategies, probably due to better access to updated technology and sustainability education programmes. Desflurane is used in 6 to 12% of the cases regardless of the GDP index. CONCLUSIONS Halogen gases are the most frequently used anaesthetic drugs worldwide. The majority of respondents are unaware of their global warming impact, or are not influenced in their anaesthetic choices by environmental concerns. More sustainable alternatives of anaesthesia are under-implemented, and vary significantly among countries depending on their GDP index. Further education and training in sustainability is needed.