The carbon footprint of general anaesthesia in adult patients: a multicentre observational comparison of intravenous and inhalation anaesthetic strategies in 35,242 procedures

Abstract

Background: General anaesthesia is a significant contributor to healthcare-related greenhouse gas (GHG) emissions. Previous studies have compared non-optimised anaesthesia strategies (desflurane, nitrous oxide, or both) to evaluate the impact of green initiatives on reducing the carbon footprint of anaesthesia. However, modern halogenated anaesthesia techniques, including low fresh gas flow and target-controlled inhalation anaesthesia (TCIA), offer potentially more environmentally friendly alternatives. Thus, we aimed to compare the GHG emissions of total intravenous anaesthesia (TIVA) with these newer techniques.

Methods: This multicentre study compared GHG emissions per hour of general anaesthesia in adult surgical patients between three anaesthetic strategies: TIVA with propofol, sevoflurane in TCIA mode, and manually optimised sevoflurane. The study was conducted in three French university hospitals, each using one anaesthesia strategy. The quantity of anaesthetic drugs used was obtained from pharmacy procurement records and converted to carbon dioxide equivalents (CO₂e). The primary outcome was the total GHG emissions per hour of anaesthesia for each strategy, including sevoflurane, propofol, and syringe consumption.

Results: TCIA, manually optimised sevoflurane, and TIVA strategies were used in 7873, 15 461, and 10 717 anaesthetics, respectively. The carbon footprint of the principal anaesthetic drugs per hour of anaesthesia was significantly lower in the TIVA strategy, at 0.4 kg CO₂e per hour, compared with 3.1 kg CO₂e per hour in the TCIA strategy and 3.8 kg CO₂e per hour in the manually optimised sevoflurane strategy.

Conclusions: TIVA with propofol was the most effective approach for minimising greenhouse gas emissions in anaesthesia practices. However, if TIVA were used exclusively globally, it could lead to issues such as stock depletion, plastic pollution, and water contamination.

Keywords: anaesthesia; carbon footprint; climate change; global warming potential; greenhouse gas emissions; sustainability; target-controlled inhalation anaesthesia; total intravenous anaesthesia.