Environmental sustainability: Overview

The excessive growth of the health sector has created an industry that, while promoting health, is now itself responsible for a significant part of global environmental pollution. The health crisis caused by climatechange urges us to transform healthcare into a sustainable industry. This review aims to raise awareness about this issue and to provide practical and evidence-based recommendations for anaesthesiologists

Background: Inhaled halogenated anesthetics are responsible for half of operating room total greenhouse gas emissions. Sustainable anesthesia groups were set up in 4 Lyon, France, university hospitals (Hospices Civils de Lyon) in January 2018 and have supported a specific information campaign about the carbon footprint related to the use of inhaled halogenated anesthetics in June 2019. We aimed to assess whether implementing such information campaigns was associated with a decrease in the carbon footprint related to inhaled halogenated anesthetics.

Methods: This retrospective cohort study was conducted from January 1, 2015, to February 29, 2020, in 4 hospitals of the Hospices Civils de Lyon in France. Information meetings on sustainable anesthesia practices were organized by sustainable anesthesia groups that were set up in January 2018. In addition, a specific information campaign about the carbon footprint related to inhaled halogenated anesthetics was conducted in June 2019; it was followed by a questionnaire to be completed online. The monthly purchase of sevoflurane, desflurane, and propofol was recorded, and the estimated monthly carbon footprint from desflurane- and sevoflurane-related perioperative emissions was calculated. The interrupted time-series data from January 2015 to February 2020 were analyzed by segmented regression, considering both interventions (setting up of the sustainable anesthesia groups and specific information campaign) in the analysis and adjusting for 2 confounding factors (seasonality of the data and number of general anesthesia uses).

Results: Among the 641 anesthesia providers from the study hospitals, 121 (19%) attended the information meetings about the carbon footprint of inhaled halogenated anesthetics, and 180 (28%) completed the questionnaire. The anesthetic activity from all 641 providers was considered in the analysis. After the sustainable anesthesia groups were set up, the carbon footprint of sevoflurane and desflurane started decreasing: the slope significantly changed (P < .01) and became significantly negative, from -0.27 (95% confidence interval [CI], -1.08 to 0.54) tons.month-1 to -14.16 (95% CI, -16.67 to -11.65) tons.month-1. After the specific information campaign, the carbon footprint kept decreasing, with a slope of -7.58 (95% CI, -13.74 to -1.41) tons.month-1 (P = .02), which was not significantly different from the previous period (P = .07).

Conclusions: The setup of the sustainable anesthesia groups was associated with a dramatic reduction in the carbon footprint related to halogenated anesthetics. These results should encourage health care institutions to undertake information campaigns toward anesthesia providers so that they also take into account the environmental impact in the choice of anesthetic drugs, in addition to the benefits for the patient and economic concerns.

Abstract
Background: Tackling the climate emergency is now a key target for the healthcare sector. Avoiding inhalational anaesthesia is often cited as an important element of reducing anaesthesia-related emissions. However, evidence supporting this is based on adult practice. The aim of this study was to identify the difference in carbon footprint of inhalational and i.v. anaesthesia when used in children.

Methods: We used mathematical simulation models to compare general anaesthetic techniques in children weighing 5-50 kg for TIVA, i.v. induction then inhalational maintenance, inhalational induction then i.v. maintenance, and inhalational induction and maintenance. We simulated inhalational induction with sevoflurane alone, and co-induction with sevoflurane and nitrous oxide, and both remifentanil-propofol and propofol-only i.v. anaesthesia. For each technique, we drew on previously published life-cycle data to calculate carbon dioxide equivalents for anaesthetic durations up to 480 min.

Results: TIVA with propofol and remifentanil had a smaller carbon footprint over a typical anaesthetic duration of 60 min (1.26 kg carbon dioxide equivalents [CO2e] for a 20 kg child) than i.v. induction followed by inhalational maintenance (2.58 kg CO2e) or inhalational induction and maintenance (2.98 kg CO2e). Inhalational induction followed by i.v. maintenance only had a lower carbon footprint than inhalational induction and maintenance when used in longer procedures (>77 min for children 5-20 kg; >105 min for children 30-50 kg).

Conclusions: In a simulation study, i.v. anaesthesia had climate benefits in paediatric anaesthesia. However, when used after inhalational induction, benefits were only achieved in longer procedures. These findings provide evidence-based guidance for reducing the environmental impact of paediatric anaesthesia, but these will require confirmation using real-world data.