How I Do It: Edmonton Perspectives in Providing Sustainable Anesthesia
Nov 5, 2018
Major industries around the world have been moving toward a more environmental and sustainable system with target environmental goals to reduce waste and greenhouse gas emissions. The industries have saved billions of dollars in such initiatives, but determining the specific profits a sustainable practice can achieve is difficult because the initiatives are reflected in cost savings rather than direct monetary profits.1 However, environmental and economic goals are most often aligned, and the mentality of “lean and green costs more” is an inaccurate and short-sighted approach.
Plastic waste represents the cost of the convenience world, and the tiny choices we make between reusable and disposable equipment determine whether we contribute to the heavy environmental burden of microplastics.
Interestingly, no guidelines or recommendations discuss the carbon footprint in the healthcare system, yet healthcare is one of the major contributors to greenhouse gas emissions and hence indirectly contributes to the healthcare burden.2 However, many health workers are unaware of it.
Anesthesia is a specialty that uses greenhouse and ozone-depleting gases. Because sterile instruments and syringes are required, we use plastic products with multiple plastic packaging. Most sustainability initiatives involve a 3R approach: reduce, reuse, and recycle. Our anesthesia practice’s equipment and quality assurance committee has adapted the same approach, which is summarized in this article. We also delineate future ideas to minimize our carbon footprint.
Sources of Waste Generation
To implement changes, we must have a basic understanding of our specialty’s contribution to the environmental burden. The main sources of pollutants from our practice stem from equipment, intravenous (IV) pharmaceuticals, and inhalational agents. Although energy use in operating rooms and the way that energy is generated are major determinants of greenhouse impact from operating rooms, such consumption is not entirely within our control and is many times determined by building codes and facilities management. Hence, the article will not cover those aspects.
Inhalational agents: Inhaled anesthetics are well-known, potent greenhouse gases.3–6 Global warming potential (GWP) is a commonly used metric to compare the potency of greenhouse gas in absorbing infrared radiation. Inhaled anesthetics such as halothane, isoflurane, and nitrous oxide (NO2) have additional ozone depleting potential (ODP). Inhaled anesthetics have vastly different environmental impacts, so we ought to choose the inhaled anesthetic with the least GWP and ODP. Desflurane by far has the highest GWP, and isoflurane and NO2 have ODP. NO2 use has been declining in practice in the Edmonton zone and, except for pediatric and obstetrics anesthesia, has become almost nonexistent. A second reason for not using NO2 is its long atmospheric lifetime.
Figure 1. Inhalation Agents on the Machine With the removal of desflurane, anesthesiologists may be more inclined to use sevoflurane.
We have reduced use of agents with high GWP (eg, desflurane) and high ODP eg, (isoflurane, NO2). One strategy to encourage reflection before use is to remove the desflurane vaporizer from the anesthesia gas machine (AGM) and store it in an accessible but separate location. (See Figure 1.)
- Through staff education, we reduced fresh gas flow during anesthetic administration. Current AGM can deliver minimal and even metabolic fresh gas flows and, in conjunction with modern carbon dioxide absorbents, circumvent the problem with carbon monoxide or compound A generation. This not only reduces the carbon footprint but also makes substantial economic sense.
- Regional anesthesia has been one of the key components in reducing the use of inhaled or IV anesthetics. We have used regional anesthesia as the sole anesthetic for most upper- and lower-limb procedures with no or minimal sedation. This omits not only the use of anesthetic agents but also other medications and equipment needed for general anesthesia.
Reuse and recycling of inhaled anesthetics is not currently possible, but technologies are in development that may enable those strategies in the future.
Solid waste: Healthcare waste is growing rapidly as predicted by the expansion in medical waste management market.7 True biomedical waste represents only about 10% of all waste, and the rest is non-risk and potentially recyclable.8 In 2018, Earth Day Network pledged to end plastic pollution. Unfortunately, plastics are commonly used in the manufacture and packaging of anesthesia equipment; hence, minimizing their use and what happens to them after use is essential. Plastic waste represents the cost of the convenience world, and the tiny choices we make between reusable and disposable equipment determine whether we contribute to the heavy environmental burden of microplastics.
Figure 2. Types of Reusable Supraglottic Airways
One of the changes we made is using reusable supraglottic airway devices (SGA) as a standard of care instead of single-use SGA. (See Figure 2.) Reusable SGA are made of recyclable silicone, whereas single-use SGA are often made from plastics, many of which are not recyclable. In rare circumstances, such as patients needing isolation precautions, disposable SGA still need to be used.9
- The drapes and covers commonly used when performing invasive procedures such as arterial cannulation and peripheral nerve block catheters are another source of solid waste. Except for central venous catheters and neuraxial procedures, all other procedures use a customized, reusable tray with reusable drapes. (See Figure 3.) This was initiated with the evidence that reusable drapes and gowns are more environmentally sustainable in terms of usage of energy, water, carbon footprint, solid waste and volatile organic generation, and material recovery.10
Figure 3. Sterile, Customized Reusable Tray for Invasive Procedures Our institution’s customized reusable tray contains reusable sterile drapes, sterile stainless steel containers for local anesthetics or other fluids used for the procedures, and scissors, needle drivers, and Kelly scissors.
Segregation of solid waste is another project long envisioned at our hospital. The anesthesiologist sorts solid waste directly in the operating room into color coded bags. Recyclable materials, such as paper, packaging materials, IV tubing, IV bags, glove covers, volatile anesthetic refill bottles, breathing circuits, warming blankets, and used syringes, are collected in a recycling bin. Any material with obvious contamination, such as blood bags, soiled syringes, endotracheal tubes, and single-use SGA, is disposed into a black garbage bag marked for landfill. All glass material is segregated into a separate bin, not the sharps bin. (See Figure 4.) Sharps bins are autoclaved, shredded, and disposed marked for landfill. Just by implementing a recycling program, we have decreased solid waste generation from our operating rooms by around 40%.
- Using the sharps bins for sharps only (See Figure 5.) will reduce filling with waste that can be recycled or otherwise disposed of. Also, it is cost effective. Going forward, we intend to use reusable sharps bins that have been shown to decrease the carbon footprint by 84% in a recent non-peer reviewed study.11
Figure 4. Recycle Bins and Anesthetic Cart in the Operating Room Having the recycle bins (plastic on the left, glass on the right) near the anesthetic cart encourages anesthesiologists to use them before putting anything in the black garbage bin which goes to the landfill.
Each recycling facility will evaluate the waste using criteria and a threshold of acceptable quantity of contaminants before rejecting the recycled plastics in the composition.
- Ask your hospitals to be a part of organizations such as Health Care Without Harm, Practice Greenhealth, or Canadian Coalition for Green Health Care, and urge them to procure products from manufacturers who are ISO/TS 14067:2013 certified, which provides the carbon footprint of their products. Further resources on sustainable practice can be obtained online.12–14
Unless we unite our efforts and put pressure on manufacturers to produce environmentally conserving products and packaging or offer packaging take-back programs, they will not be forthcoming in sustainability advancements.
Figure 5. Self-Locking and Sealable Sharps Container Our current sharps container has a needle adaptor to safely remove the needle from a syringe, allowing disposal of only the needle rather than the whole unit of needle and syringe.
Oral and IV pharmaceuticals have the potential for persistence, bioaccumulation, and toxicity in ground water and the food chain. Many of the drugs used in anesthesia, in particular propofol, have been shown to accumulate in the water cycle and life cycle of aquatic organisms.15 The long-term impact of exposure to those pharmaceuticals in the environment is currently unknown.
The fact that concentrations of prescription pharmaceuticals are rising in the environment necessitates that we pay attention to how economically we use drugs during anesthesia and where we discard unused medications. Because current water treatment facilities are not 100% effective in removing pharmaceuticals, the World Health Organization recommended that source control is the best way to reduce pharmaceutical presence in the environment.16
Prefilled syringes are an ideal way to decrease drug wastage. Although some resuscitation medications, such as atropine and epinephrine, are typically available only prefilled, others such as ephedrine, phenylephrine, or local anesthetics used for regional anesthesia are often overdrawn and underused.
We are working with our inpatient pharmacy to obtain a dedicated drug refrigerator for prefilled syringes with most of the vasoactive agents, local anesthetic solutions, heparin, and succinylcholine. We are also in the process of installing low-volume drug collection bins in each operating room that will be marked for incineration at high temperatures.
Anesthesiologists and other healthcare professionals must understand our impact on the environment. Many other industries have implemented environmental conservation strategies. We strive to improve clinical outcomes for our patients; yet, the fundamental well-being of humanity is a healthy planet Earth. The transformation process is more streamlined if it is led by a sustainability champion in the department or hospital. As anesthesiologists, our role in the perioperative setting makes us an ideal specialty to be engaged and play an active part in sustainability.
- Zokaei, K. Environmentally-friendly business is profitable business. The Guardian. https://www.theguardian.com/sustainable-business/environmentally-friendly-sustainable-business-profitable. Accessed September 7, 2018.
- Eckelman MJ, Sherman J, Davies M, Adair H, Armstrong B, Barrett M. Environmental impacts of the U.S. health care system and effects on public health. PLoS One. 2016;11:e0157014. https://doi.org/10.1371/journal.pone.0157014
- Sulbaek Andersen MP, Nielsen OJ, Karpichev B, Wallington TJ, Sander SP. Atmospheric chemistry of isoflurane, desflurane, and sevoflurane: kinetics and mechanisms of reactions with chlorine atoms and OH radicals and global warming potentials. J Phys Chem A. 2012;116:5806–5820. https://doi.org/10.1021/jp2077598
- Meyer L, Brinkman S, van Kesteren L, Leprince-Ringuet N, van Boxmeer F. Climate hange 2014: synthesis report. Geneva, Switzerland: Intergovernmental Panel on Climate Change; 2014. http://www.ipcc.ch/report/ar5/syr/
- Sherman J, Le C, Lamers V, Eckelman M. Life cycle greenhouse gas emissions of anesthetic drugs. Anesth Analg. 2012;114:1086–1090. https://doi.org/10.1213/ANE.0b013e31824f6940
- Ryan SM, Nielsen CJ. Global warming potential of inhaled anesthetics: application to clinical use. Anesth Analg. 2010;111:92–98. https://doi.org/10.1213/ANE.0b013e3181e058d7
- Medical waste management market estimated to exhibit 5% CGR through 2025. Digital Journal. http://www.digitaljournal.com/pr/3791499. Accessed September 20, 2018.
- Chartier Y, Emmanuel J, Pieper et al. Safe management of wastes from health-care activities. Second edition. World Health Organization. Available at: http://apps.who.int/iris/bitstream/handle/10665/85349/9789241548564_eng.pdf;jsessionid=4E5203FEC2DA0AE165DACBE93081CAF3?sequence=1 Accessed 20 Sept 2018.
- Blunt M, Burchett KR. Variant Creutzfeld-Jakob disease and disposable anesthetic equipment—balancing the risk. 2003;90(1):1–3.
- Overcash M. A comparison of reusable and disposable perioperative textiles: sustainability state-of-the-art 2012. Anesth Analg. 2012;114(5):1055–1066. https://doi.org/10.1213/ANE.0b013e31824d9cc3
- McPherson B, Sharip M, Grimmond T. The impact on global warming potential of converting from disposable to reusable sharps containers in a large US hospital Geogrphically distant from polumer and container manufacturer. Peer J Preprint. https://doi.org/10.7287/peerj.preprints.26517v2
- Canadian Coalition for Green Health Care. http://greenhealthcare.ca. Accessed September 7, 2018.
- Global Green and Healthy Hospitals. About. https://noharm-global.org/issues/global/global-green-and-healthy-hospitals. Accessed September 7, 2018.
- Practice Greenhealth. https://practicegreenhealth.org. Accessed on September 7, 2018.
- Russell F.Mankes. Propofol Wastage in Anaesthesia. Anesth Analg. 2012 May;114 (5):1091-2.