Trends in greenhouse gas emissions from volatile anaesthetics in 41 countries: 2013-2023.

INTRODUCTION Inhalational anaesthetics contribute to greenhouse gas emissions, leading to regulatory restrictions in some countries. This study analysed time trends of greenhouse gas emissions directly attributable to the use of volatile anaesthetic agents in 41 countries. METHODS Sales data were obtained using data from IQVIA MIDAS® and national medicines agencies. We calculated the kilograms of carbon dioxide equivalents (based on global warming potential) per capita and percentage change in greenhouse gas emissions, from the emission of volatile anaesthetics from 2018 to 2023. RESULTS Data were obtained for 41 countries, representing approximately 35% of the global population. Greenhouse gas emissions associated with volatile anaesthetic agents decreased in the 27 European Union nations and other 'western' countries included in the study (Australia, Canada, New Zealand, UK and USA), achieving in some cases below 0.5 kg of carbon dioxide equivalents per inhabitant. In contrast, several Asian countries showed a substantial increase in emissions, with South Korea and Japan reporting the highest values globally (approximately 2.5 kg of carbon dioxide equivalents per inhabitant). A secondary analysis restricted to European countries showed a 17-fold difference in per-capita carbon-equivalent emissions between the highest and lowest emitters, suggesting that recommendations on the use of volatile anaesthetic agents are implemented inconsistently. DISCUSSION Our study highlighted large differences in the management of greenhouse gas emissions attributable to volatile anaesthetic use. While results show a decreasing trend in western countries, albeit with substantial variation, rising trends observed in many Asian countries may constitute a source of concern. The experience of nations that have phased out the highest impacting volatile anaesthetic agents show that reducing emissions below 0.5 kg of carbon dioxide equivalents per inhabitant is attainable. This should serve as a model for other systems, prompting implementation of educational initiatives and specific policies.