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Background and Aims Total intravenous anaesthesia (TIVA) and regional anaesthesia (RA) have been touted as environmentally preferable alternatives to volatile anaesthesia, however few studies have investigated the relative environmental impact of these anaesthetic techniques.

Methods A retrospective observational database study was conducted, in which theatre billing records were obtained. For each pharmaceutical, single-use disposable and their primary packaging, carbon equivalent emissions (CO2e) were calculated using a bottom-up cradle-to-grave life cycle methodology. These values were summated for each case and compared between patients receiving desflurane (DES), sevoflurane (SEVO), RA or TIVA. Theatre time for each case was used to model CO2e contributions from medical gas, carbon dioxide absorber and theatre energy consumption. Total solid waste was also compared.

Results A total of 2 061 cases were studied. Mean CO2e for DES was 147.02 (95%CI 137.98 – 156.06)kgCO2e, SEVO 13.87 (95% CI 13.58 – 14.18)kgCO2e, RA 8.05 (95% CI 7.27 – 8.83)kgCO2e and TIVA 8.97 (95% CI 8.50 – 9.44)kgCO2e. When including the contributions modelled from theatre time, mean CO2 for DES was 147 (95% CI 138.41 – 156.51) kgCO2e, SEVO 14.29 (95%CI 13.98 – 14.60)kgCO2e, RA 9.204 (95% CI 8.358 – 10.051) kgCO2e and TIVA 9.86 (95% CI 9.37 – 10.34)kgCO2e. Mean solid waste contribution for DES was 0.84 (95% CI 0.81 – 0.87) kg, SEVO 0.82 (95% CI 0.81 – 0.84)kg, RA 0.74 (95% CI 0.68 – 0.80)kg; and TIVA 0.95 (95% CI 0.91 – 0.99)kg.

Conclusions The current study suggests that regional anaesthesia is preferable to alternatives when considering carbon emissions and solid waste production.