Jul 30, 2018, 09:36 AM by Rakesh Sondekoppam Vijayashankar, MBBS, MD; Timur J.P. Ozelsel, MD; Vivian H.Y. Ip, MBChB, MRCP, FRCA; Ban Tsui, MD, MSc, FRCPC

“One touch of nature makes the whole world kin.” Ulysses expresses this in Shakespeare’s Troilus and Cressida to indicate that through a shared feeling or goal, we all become siblings (in a sense of belonging). In contemporary medical practice, our consideration for nature and the environment is similarly necessary to make us feel like we belong to society.

The practice of medicine was borne out of compassion toward those who are suffering and the constant desire to explore, explain, and address various maladies. Pain and suffering had been a part of humanity's story until the discovery of analgesic and anesthetic agents. The development of the specialty of regional anesthesia and acute pain medicine is a true testament to the human effort to address the pain and suffering of humanity, leading to unprecedented improvements in medical and surgical care. For the first time, previously lethal maladies or afflictions could be easily cured. Although advancements in medicine have basic tenets in extending compassion to those in need, sadly, the greater good to the society and the social responsibility of health care in terms of environmental impact have been underrecognized.

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“The provision of health care is one of the biggest contributors to global climate change. Regional anesthesia can play a leading role in the provision of ‘Green Anesthesia.’”

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The World Health Organization (WHO) constitution identifies the enjoyment of the highest attainable standard of health as one of the “fundamental rights of every human being without distinction,”^[1] and our role as physicians is to provide access to health-enabling conditions. Unfortunately, the uphill task for us in the health care field, as WHO duly acknowledged, is that climate change is the greatest threat to global health in the 21st century^[2] and that the provision of health care is one of the biggest contributors to the problem. Recent studies have estimated that health care is responsible for approximately 4–10% of the total United States greenhouse gas (GHG) emissions and has increased 30% during the past decade.^[3]

It is the opinion of this special interest group (SIG) that anesthesiologists should be on the correct side of this debate and take measures to decrease the environmental impact of our practice, hence reducing our indirect burden on health care. The SIG plans to lead by example and to promote environmentally friendly practices in anesthesia through education and generation of evidence. The SIG's focus will be sufficiently broad so as to encompass the full spectrum of “green anesthesia” and will not be limited only to the environmental impact of regional anesthesia. Through the creation of this SIG, we intend to encourage research, publication, and education across the following fields.

General Anesthesia and The Environment

A recent study of operating room (OR) practices in three health systems by MacNeill et al^[4] demonstrated how we can minimize our GHG impact by simply changing to a volatile anesthetic with a lesser carbon footprint. All inhaled anesthetics are potent GHGs of varying degrees, and some, like nitrous oxide and isoflurane, also destroy the ozone layer. Fortunately, the greenhouse impact of volatile anesthetics varies greatly, with the least GHG effect coming from sevoflurane and isoflurane and the maximal effect from desflurane and nitrous oxide. Hence the adage “short-term gain for long-term pain” aptly fits when one chooses to use desflurane or nitrous oxide because they have higher carbon dioxide (CO2 ) burdens and longer half-lives (Figure 1).

Because inhalational anesthetics do not fall under mandatory lists of agents reported by the pollution-monitoring agencies and are also the only agents left out of the Montreal Protocols list of halogenated fluorocarbons to be phased out by 2030, market research expects an increase in the consumption of inhalational anesthetics in the range of 10–15% per year. Our own practice habits, including the choice of inhalational anesthetic and the fresh gas flows we run, largely determine what impact our anesthetics make on the environment.

General anesthesia via intravenous agents is undoubtedly far better for the atmosphere, but it comes with its own set of problems. Our pharmaceuticals will reach soil and water either through excretion of the unchanged product or its metabolites or as waste occurring in the OR. We need to further our understanding of the life cycle of our medications and how they impact our ecology and population health. With all this in mind, one of the SIG's goals is to bring components of environmental sustainability into the practice of all anesthesiologists through educational initiatives. Some of the SIG's educational objectives are to advocate for improved and financially beneficial technology. Xenon, for example, has no known environmental impact and should likely receive additional attention and research.

Various metrics exist or are being developed to assist in our understanding of GHGs' impact on the atmosphere and their role in climate change. However, our understanding remains far from complete. Global warming potential—or the more appropriately termed relative cumulative forcing index—is an index of the total energy added to the climate system by our inhalation anesthetics relative to that added by CO2 , which was most recently updated in the fifth Assessment Report by the Intergovernmental Panel on Climate Change. Furthering all our understanding of the metrics, as well as their values and shortcomings, is an important SIG goal to advance research and communication in this area.

Regional Anesthesia and the Environment

Regional anesthesia is an elegant modality to reduce or to avoid general anesthesia and can potentially play a leading role in green anesthesia. It has repeatedly proven benefits, including improved pain control and functional outcomes. Potential reductions in cancer recurrence or chronic pain require more compelling evidence (Figure 2) before they can be widely accepted as fact. Logic suggests that regional anesthesia is currently the anesthetic with the lowest environmental burden. Hence this presents us with a great opportunity to generate evidence and determine the favorable environmental impact of regional anesthesia either as a sole anesthetic or in combination with general anesthesia. One of the SIG's main goals is to launch projects exploring the environmental impact of various anesthetic techniques including regional anesthesia.

Waste in the OR

Planetary resources are finite, and it is important to be responsible in their use. Media marketing increasingly promotes disposable OR equipment. However, the environmental impact of such an approach is not entirely clear. It will be important to generate independent life-cycle analyses for various equipment and to determine where reusable options might be more environmentally responsible.

Medication waste is another major issue that causes not only the aforementioned problems with soil and groundwater pollution, but also financial losses in the range of hundreds of millions of dollars per year. The downstream effects of such waste require significant research, which is in its infancy.

These examples are mere starting points for the field of green anesthesia. Progress will likely include rethinking tendencies and practices that have become prevalent in anesthesia in particular and medicine in general. Yet it is up to us to generate interest and help address the problems of climate change and environmental destruction.

History and Structure of the SIG

The Green Anesthesia SIG was approved at the ASRA board meeting in September 2017. We have 13 founding ASRA members and have appointed the following positions at inception:

Chair	Timur Özelsel
Co-chair	Ban Tsui
CME liaison	Edward Mariano
Newsletter liaison	Vivian Ip
Webcast liaison	Jean-Louis Horn
Website liaison	Rakesh Sondekoppam

The SIG's goals are as follows:

• To promote international collaboration for the development and advancement of environmentally sustainable practices in anesthesia
• To encourage research projects exploring the environmental benefits of regional anesthesia
• To promote implementation of regional anesthesia techniques by anesthesiologists with the goal of minimizing environmental burden from our practice
• To promote education in environmental sustainability in anesthetic practice.

The field of green anesthesia offers ample opportunities for research and education, and we look forward to welcoming more members to our SIG. Membership is free for all ASRA members; join by registering on the ASRA website or by contacting membership services. We urge as many members as possible to get involved in the SIG. We look forward to welcoming you to our SIG and working toward changing practices that will enable a sustainable and bright future for all life. Anesthesiologists and physicians in general should consider making the Hippocratic injunction of “first do no harm” applicable not just to their patients but to all society. Establishing this SIG is a vital step in that direction.

References

1. World Health Organization. Constitution of the World Health Organization. 1946. Available at: http://apps.who.int/gb/bd/PDF/bd47/EN/constitution-en.pdf?ua=1. Accessed March 6, 2018.
2. World Health Organization. WHO calls for urgent action to protect health from climate change – sign the call. Available at: http://www.who.int/globalchange/ global-campaign/cop21/en/. Accessed March 6, 2018.
3. Chung JW, Meltzer DO. Estimate of the carbon footprint of the US health care sector. JAMA. 2009;302:1970–1972.
4. MacNeill AJ, Lillywhite R, Brown CJ. The impact of surgery on global climate: a carbon footprinting study of operating theatres in three health systems. Lancet Planet Health. 2017;1(9):e381–e388.