Contributions of Medical Greenhouse Gases to Climate Change and Their Possible Alternatives.

Considerable attention has recently been given to the contribution of the greenhouse gas (GHG) emissions of the healthcare sector to climate change. GHGs used in medical practice are regularly released into the atmosphere and contribute to elevations in global temperatures that produce detrimental effects on the environment and human health. Consequently, a comprehensive assessment of their global warming potential over 100 years (GWP) characteristics, and clinical uses, many of which have evaded scrutiny from policy makers due to their medical necessity, is needed. Of major interest are volatile anesthetics, analgesics, and inhalers, as well as fluorinated gases used as tamponades in retinal detachment surgery. In this review, we conducted a literature search from July to September 2024 on medical greenhouse gases and calculated estimates of these gases' GHG emissions in metric tons CO equivalent (MTCOe) and their relative GWP. Notably, the anesthetics desflurane and nitrous oxide contribute the most emissions out of the major medical GHGs, equivalent to driving 12 million gasoline-powered cars annually in the US. Retinal tamponade gases have markedly high GWP up to 23,500 times compared to CO and long atmospheric lifetimes up to 10,000 years, thus bearing the potential to contribute to climate change in the long term. This review provides the basis for discussions on examining the environmental impacts of medical gases with high GWP, determining whether alternatives may be available, and reducing emissions while maintaining or even improving patient care.