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

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.

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.

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. SF_6, 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.

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".