The use of fluorinated gases and quantification of carbon emission for common vitreoretinal procedures.

Abstract

Purpose: To report the contribution to carbon dioxide equivalent mass [CO2EM] of various types of VR surgery performed across three tertiary referral centres, according to their indication and fluorinated gas used. We secondarily reported on the difference in tamponade choice, and CO2EM between the different centres.

Materials: Retrospective, continuous, comparative multicentre study of all procedures using fluorinated gases between 01/01/17-31/12/20 at the Manchester Royal Eye Hospital and Birmingham and Midland Eye Centre, and between 01/01/19-31/12/2020 at the University Hospitals Coventry and Warwickshire.

Results: Across 4877 procedures, the use of fluorinated gases produced 284.2 tonnes (71.2 tonnes annually) CO2EM; an annual consumption of 30,330 l of gasoline. Rhegmatogenous-retinal-detachment (RRD) and macular hole repair had the highest CO2EM by indication, accounting for 191.4 tonnes CO2EM (67.3%) and 28.6 tonnes CO2EM (10.1%); a mean 60.0 kg and 32.0 kg of CO2EM produced per surgery respectively. The use of fluorinated gases and their respective CO2EM contributions were significantly different across all three centres (p < 0.001) for all indications. SF6, despite being used in 1883 procedures (38.6%), contributed to 195.5 tonnes CO2EM (68.8%). Relative to C2F6, procedures using C3F8 and SF6 produced 1.9 and 4.4 times more CO2EM.

Conclusion: We demonstrated that SF6 causes significantly higher carbon emissions relative to C2F6 and C3F8 with RRD and macular hole repair having the greatest environmental impact. We also reported large variations between different large VR centres in fluorinated gas use, and therefore in carbon emission contributions depending on indications for surgery. Evidence-based protocols might help in making VR surgery "greener".