“The earth is in the midst of an environmental crisis, driven largely by human activity. In our work and personal lives, we all bear responsibility for this, and for the harm it causes to others.”1
Sustainable work practices can be maintained well into the future by conserving an ecological balance that avoids depleting natural resources or irreversibly disrupting ecosystems. The importance of health care practices for improving environmental sustainability has been illustrated by audits finding that over 8% of the United States' total CO2 emissions2 originates from the health care system and that the English National Health Service (NHS) is responsible for over 3% of England's total CO2 emissions (Table 1, ref. 1). The transition to sustainability can be guided by life cycle assessment (LCA), a scientific method increasingly used to determine the entire “cradle to grave” environmental and financial effects of processes and products.3,4
While some hospital sectors and organizations have made great efforts to improve hospital sustainability practices (Table 1, refs. 2–6), anesthesiologists appear to have had only a limited role in these endeavors to date. The practice of anesthesia, however, has far reaching environmental effects:
- during one average working day an individual anesthesiologist, administrating N2O or desflurane can contribute the CO2 equivalent of more than 1,000 km (620 miles) of car driving5–8;
- annually worldwide, anesthetic gases are estimated to have the same global warming potential as one million American passenger cars9;
- every day of the year United States operating room staff will deposit into landfill more than 1,000 tons of rubbish (Table 1, ref. 7), of which anesthetic practice is likely to contribute 1/4 of the total.10
In this commentary we explore: (1) the role of life cycle assessments (LCAs) for anesthetic agents and medical devices, (2) the “reduce, reuse and recycle” waste hierarchy in the operating room and (3) advocating for environmentally sustainable practices. We refer readers to recent articles by Sherman and Ryan,11 the American Society of Anesthesiologists (Table 1, ref. 8), and our own group (Table 1, ref. 9) for a broader examination of sustainability within anesthesia.
Life Cycle Assessments typically incorporate the entire “footprint” (financial and environmental costs) of an item or process. This footprint includes: 1) raw material acquisition, 2) processing and manufacturing, 3) distribution and transportation, 4) use, reuse and maintenance, 5) recycling and 6) waste management.3 As anesthesiologists, everything we use and do has a footprint, whether this be for an item, such as a single use or reusable laryngeal mask, or a procedure (e.g. a regional anesthetic). LCA allows us to achieve rational product and practice choices that reflect true environmental and financial costs beyond short-term effects. Further, LCA provides structure and method for a nascent field of medical research, i.e. how sustainable are our practices?
Importantly, environmental factors beyond CO2 emissions, including water consumption and release of toxic byproducts can be calculated in an LCA. Comparisons between items may indicate relative advantages for one outcome (e.g. CO2 emissions), which may be contrary to other outcomes (e.g. water use/contamination). Environmental databases such as Gabi and EcoInvent (Table 1, refs. 10 and 11) incorporate geographically specific average industry data (e.g. the estimated CO2 emissions from burning coal from a defined region) and are often used in LCA modelling because directly collecting all data would make most LCAs unviable. It is acknowledged that average industry data have greater associated uncertainty than directly measured data.12,13 In the late 1990s, standardization of how LCAs should be conducted was achieved when the International Organization for Standardization (ISO) released the ISO 14000 series (Table 1, ref. 12). Starting with Coca-Cola bottles in 1969 (Table 1, ref. 13), a multitude of LCAs from a diverse range of industries have been undertaken. However comparatively few LCAs have involved medical items and practices (Table 1, ref. 14).14–20
LCAs could improve our understanding of the comparative environmental costs of inhaled anesthetics. Whilst the potent, direct, global warming potential of inhalational agents have been described,5–9 there is no publically available information about their total environmental effects (including manufacturing and distribution)21 which could be considerably greater than their known direct global warming effects. Without knowledge of the full life cycle of an inhalational agent it could be inaccurate to state that desflurane has a much higher greenhouse enhancing effect than other inhalational agents. Similarly, despite the promising technology allowing the reuse of volatile gases9,23 (Table 1, refs. 15 and 16), LCAs that compare the total environmental effects of such reuse to the current practice of using fresh volatile anesthetic agents are warranted.
To assess some of the environmental uncertainties of general anesthetic agents our research group proposed an LCA of three generic agents: N2O, sevoflurane, and propofol. This study was planned to include the potential environmental toxicities of the agents on fresh water (propofol is a hindered phenol) and other ecosystems (Table 1, ref. 17).22 Although the general processes required to manufacture N2O are well known (fertilizer production), details of the manufacture of sevoflurane and propofol are not in the public domain, thus industry co-operation is integral. Despite repeated written requests for information regarding the manufacturing of sevoflurane and propofol our planned research could not proceed due to manufacturers' concerns that included commercial confidentiality and perceptions of methodological difficulty. Our experience with previous LCAs however, is that commercially sensitive details are often not required, or appropriate commercial-in-confidence agreements can be made without undermining the scientific integrity of the reported LCA.
There are no legal obligations requiring medical companies to analyze and provide the environmental effects of their products, although some supermarkets do. The fundamental barriers to performing LCAs appear to be primarily industry resistance, (i.e., the commercial implications of comparing processes or items, suggesting “winners and losers”) and the costs of performing the study rather than research or professional concerns. LCAs are expensive to perform (usually >$10,000 U.S.) primarily because of the labor costs (commonly 100 hours at a minimum) of data gathering and validation, examination of inventories and statistical interpretation. If anesthesiologists as a profession decide that the total environmental effects of what we do are important how do we gain industry co-operation for LCAs? Sustained professional pressure from medical colleges and societies upon companies would be useful, in addition to government reporting requirements (expanding from CO2 emissions reporting) and hospital procurement contractual arrangements that consider environmental footprints, such as Practice Greenhealth's recent initiative (Table 1, ref. 18). Anesthesiologists may at some stage be expected to justify the “ecotoxicity”7 of their anesthetic agents.
It is often easier to perform LCAs of medical equipment rather than medications because there is usually open access to the manufacturing methods for the former (e.g.s plastic and steel production). An LCA of anesthetic drug trays, comparing reusable (washable) to single use versions has been completed by our group, despite some industry resistance.17 Our results showed that using reusable trays was associated with similar CO2 emissions (in a city with >85% of its electricity for sterilizing and processing derived from greenhouse gas intensive brown coal), but less water consumption and lower financial costs than using single use trays. The routine packaging of cotton gauze with single use trays was associated with dramatically increased CO2 emissions, water consumption, and financial costs.
The findings of our LCA allowed for a rational choice of products based on environmental and financial data, and with this evidence, the Western Hospital (Melbourne, Australia) with six operating rooms, changed from single use trays with cotton gauze to reusable trays, with cotton used as required. This change is predicted to generate savings of US$6,500, 600kg of CO2 emissions, and 170,000 liters of water each year.17 Future life cycle assessments in anesthesia could examine reusable versus single-use laryngeal masks, laryngoscopes, surgical metal instruments, and anesthetic circuits.
The “reduce, reuse (reprocess), recycle (and segregate)” waste hierarchy, in addition to LCAs, provides a useful framework to consider the environmental effects of anesthetic practice. Methods for reducing resource consumption, CO2 emissions and waste amounts (including toxic byproducts) range from minimizing hospital admissions (improvements in primary health care and increasing out-patient procedures) to reducing the use of drugs and equipment in our daily practices. Further examples for improving both individual and organizational environmental sustainable work practices are listed in Table 2 and include: using low flow anesthesia,24 opening equipment only when needed, wearing individual, washable (reusable) operating theatre attire, removing cotton gauze from pre-packed anesthetic trays,17 turning off monitors between cases,25 and less frequent washing of reusable anesthetic circuits.26
Medical devices can be divided into three groups according to their usage: 1. single use = one use only (disposable), 2. Reusable = able to be washed and sterilized for patient reuse generally within the hospital and 3. reprocessed devices = undergo assessment, repair, sharpening, smoothing, cleaning and sterilizing before being reused. Typically reprocessing is performed external to a hospital by a third party (Table 1, ref. 19). Currently, manufacturers determine whether their product is single use (Table 1, refs. 20 and 21). There are legitimate reasons for labeling medical devices as single use including: device design precludes decontamination or likely malfunction or degradation with reuse. The widespread move however, to single use medical devices may be influenced more by perceived cost benefits and creative marketing than good evidence as potentially many single use devices can be reused or reprocessed. Further research on the validity of labeling devices as single use may have significant environmental and financial advantages and is long overdue.27
It is unclear if reprocessing is more environmentally sustainable than purchasing new items, although it is less expensive and appears to decrease landfill waste.28 Comparing reusable versus single use medical devices, the limited literature suggests that it is both an environmental and financial advantage to consider reusable devices where these exist (metal instruments, plastic trays and surgical scrub gowns) (Table 1, ref. 14).14–17 LCAs of reusable, single use and reprocessed single use devices would provide greater clarity about the entire financial and environmental costs of these three approaches.
Manufacturing products from recycled rather than raw materials is often environmentally attractive when the entire life cycle is considered (Table 1, ref. 22). Operating suite waste has been shown to form about 20% of all hospital waste.29 An important first step in recycling operating room waste is to separate infectious from non-infectious waste as infectious waste is costly in both financial and environmental terms.30 Recyclable, non-infectious waste should then be further separated (at least one-third of all operating room waste).10,30 There are still many operating suites where separating infectious and general waste occurs to a limited degree and there are inadequate recycling arrangements.10,30 Practice Greenhealth's initiative, “Greening the Operating Room” may assist with the commencement of recycling programs (Table 1, ref. 6).
Plastics form approximately 30% of operating room waste.29,30 There are multiple varieties of medical plastics which may be inadequately labeled, though guidelines exist to aid recycling.31 It can be important to separate some plastic types, such as polyvinylchloride (PVC), that are processed differently.31 PVC is used for items including intravenous fluid bags and oxygen tubing and can comprise approximately 30% of a hospitals' plastic waste.29 To our knowledge medical PVC is not routinely recycled elsewhere, although, as our pilot trial is showing (at Western Health, Melbourne, Australia) it is safe, feasible and cost-competitive to recycle PVC into agricultural pipe that would otherwise be general, non-infectious landfill.
Further examination of the scientific, social and environmental risks (resource consumption, waste management and global warming effects) of many health care practices is required. In supporting appropriate sustainable health care practice decisions we should be mindful however, that there may be potential conflicts between protecting the patient and improving environmental stewardship.32 The natural tension that exists between protecting the patient and the environment32 and concern regarding infection control risks should be managable by appropriate research and ongoing quality assurance standards.33
The World Health Organization (WHO) together with Health Care Without Harm have called on the medical profession to lead in advocating for a healthy and sustainable future (Table 1, ref. 23). In 2009 a Lancet series stated that “Climate change is the biggest global health threat of the 21st Century” and called on medical professionals to use their expertise to synthesize the emerging evidence evaluating the health effects of climate change and to be advocates for public health.34 Yet every day in the operating room we, as anesthesiologists, use greenhouse gases and together with our surgical colleagues rapidly consume resources and create large amounts of rubbish. Wider workplace and community engagement, through volunteering time and skills is not only associated with important personal benefits,35,36 but as researchers and advocates we can also broaden the evidence base surrounding workplace environmental sustainability practices, including encouraging life cycle assessments. Useful Web sites are listed in Table 1 (refs. 2–6 and 8), and actions to create environmentally sustainable work practices are found in Table 2. We recognize that there are no easy solutions to improving environmental sustainability and that time, effort and persistence are all required.
Name: Forbes McGain, MBBS, FANZCA, FCICM.
Contribution: This author helped design the study, conduct the study, analyze the data, and write the manuscript.
Attestation: Forbes McGain approved the final manuscript.
Conflicts of Interest: Forbes McGain reported no conflict of interest.
Name: David Story, MBBS, FANZCA, MD.
Contribution: This author helped design the study, conduct the study, and write the manuscript.
Attestation: David Story approved the final manuscript.
Conflicts of Interest: David Story reported no conflict of interest.
Name: Eugenie Kayak, BSc, MSc, MBBS, FANZCA.
Contribution: This author helped write the manuscript.
Attestation: Eugenie Kayak approved the final manuscript.
Conflicts of Interest: Eugenie Kayak reported no conflict of interest.
Name: Yoshihisa Kashima, BA, LLB, PhD.
Contribution: This author helped write the manuscript.
Attestation: Yoshihisa Kashima approved the final manuscript.
Conflicts of Interest: Yoshihisa Kashima reported no conflict of interest.
Name: Scott McAlister, BSc, PGradDipSci, MWaterRM.
Contribution: This author helped write the manuscript.
Attestation: Scott McAlister approved the final manuscript.
Conflicts of Interest: Scott McAlister works as a lifecycle assessment expert, and as such gains remuneration for performing lifecycle assessments. Neither Scott McAlister nor any of his family members, however, has any vested interest in any medical products.
This manuscript was handled by: Steven L. Shafer, MD.
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