Recommended
Recommended
More Related Content
Similar to Implementing a greener recovery with spinal anaesthesia
Similar to Implementing a greener recovery with spinal anaesthesia (20)
Recently uploaded
Recently uploaded (20)
Implementing a greener recovery with spinal anaesthesia
- 1. Implementing a greener recovery with spinal anaesthesia Will Rattenberry BM BCh BA (Hons) FRCA EDRA Nottingham University Hospitals @effectsite Supported by an unrestricted educational grant from
- 2. Declarations • Elected member of Association of Anaesthetists Trainee Committee • Imperfect environmentalist • No conflicts of interest @effectsite
- 3. Overview • The climate and environmental emergency • Environmental impact of anaesthesia • Environmental benefits of spinal anaesthesia and ambulatory surgery @effectsite
- 8. Aditya Irawan/NurPhoto BAY ISMOYO/AFP/Getty Images SHUTTERSTOCK Getty Images
- 9. What are we doing about it? @effectsite
- 10. COVID-19 & CO2 emissions @effectsite
- 11. Health & Social Care (England) CO2e 2017 Sustainable Development Unit. Reducing the use of natural resources in health and social care. 2018. @effectsite
- 12. NHS Long Term Plan 2019 • 2% reduction by ‘transforming anaesthetic practices’ • Reduction in single-use plastics @effectsite
- 13. Health Care Without Harm. Fostering Low-Carbon Healthcare in Europe. A Carbon Footprinting Pilot Project. https://noharm- europe.org/sites/default/files/documents-files/5341/EUKI%20overview.pdf Inhalational Anaesthetic Agents @effectsite
- 14. Vollmer, M. K et al. Modern inhalation anesthetics: Potent greenhouse gases in the global atmosphere. Geophys. Res. 2015 doi: 10.1002/2014GL062785. Atmospheric concentrations @effectsite
- 15. O2/N2O/Inhalational Tom Pierce. Anaesthetic gases calculator. Available at: https://anaesthetists.org/Home/Resources- publications/Environment/Guide-to-green-anaesthesia/Anaesthetic-gases-calculator @effectsite
- 16. Low flow O2/Air/Inhalational Tom Pierce. Anaesthetic gases calculator. Available at: https://anaesthetists.org/Home/Resources- publications/Environment/Guide-to-green-anaesthesia/Anaesthetic-gases-calculator @effectsite
- 17. Ultra low flow Tom Pierce. Anaesthetic gases calculator. Available at: https://anaesthetists.org/Home/Resources- publications/Environment/Guide-to-green-anaesthesia/Anaesthetic-gases-calculator @effectsite
- 18. TIVA Sherman J et al. Life cycle greenhouse gas emissions of anesthetic drugs. Anesth Analg. 2012. doi:10.1213/ANE.0b013e31824f6940@effectsite
- 19. Spinal anaesthesia • Lidocaine 20mg • Bupivacaine 10mg • Oxygen 6 l/min • 0.000805 kg CO2e • Does not include disposables, other drugs etc Jodi Sherman. Gassing Greener. @effectsite
- 20. Cradle-to-gate greenhouse gas emissions Parvatker, A et al. ACS Sustainable Chemistry & Engineering 2019 doi:10.1021/acssuschemeng.8b05473@effectsite
- 21. Prilocaine and 2-chloroprocaine • Environmental risk assessment • Prilocaine 2% hyperbaric • not predicted to bioaccumulate • aquatic toxicity at higher dose • ‘insignificant risk to the environment’ • 2-chloroprocaine 1% • very low predicted environmental concentration and low risk of bioaccumulation • aquatic toxicology data not required @effectsite
- 22. Other benefits • Less resource • Less waste • Less PPE • Lower risk of aquatic toxicity than propofol James French@effectsite
- 23. ‘Transforming anaesthetic practices’ • RA: wherever possible • GA: • avoid desflurane and N2O • low-flow, closed circuit • TIVA preferable Health Care Without Harm 2018@effectsite
- 24. Spinal anaesthesia for ambulatory surgery • Can improve access to day surgery • Can improve theatre efficiency and patient flow • Can allow patients to engage with therapy & reduce need for outpatient follow-up • Can reduce cost @effectsite
- 25. Environmental benefits of ambulatory surgery • Fewer on the day cancellations • Reduced complications (VTE and HAI) • Less visitor travel • Evidence of improved efficiency and reduced cost @effectsite
- 26. COVID-19 & the climate emergency • Spinal anaesthesia has major benefits for both • Golden opportunity to re-design pathways & re-consider our local status quo iberdrola @effectsite
- 27. The scale of the environmental benefits • Hospital for Special Surgery, NYC, USA • 10,485 total hip and knee arthroplasties • Only 4% GA (US average 75%) • Calculated saved 750 kg desflurane and 60 kg N2O over 1 year Kuvadia M, Cummis CE, Liguori G, et al. 'Green-gional' anesthesia: the non-polluting benefits of regional anesthesia to decrease greenhouse gases and attenuate climate change. RAPM 2020. doi:10.1136/rapm-2020-101452@effectsite
- 28. Conclusions • Spinal anaesthesia is green • Ambulatory surgery is desirable • COVID-19 provides an opportunity to change established practice and improve sustainability @effectsite
Editor's Notes
- We live on a vulnerable planet of finite resource. Earth rise picture from Apollo mission. Our atmosphere is just a slither. Around 100km above the earth’s surface it ends. This distance is only 1.57% of the earth’s radius! 80% of atmosphere is in the troposphere that ends at 10km.
- In 1896, a seminal paper by Swedish scientist Svante Arrhenius first predicted that changes in the levels of carbon dioxide in the atmosphere could substantially alter the surface temperature through the greenhouse effect. In May 2020 we are now at 414ppm, far exceeding levels over the previous 800,000 years
- The world has observed a 1°C temperature rise above pre-industrial levels, with feedback cycles and polar amplification resulting in a rise as high as 3°C in north western Canada. (In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world under the auspices of the United Nations, concluded there's a more than 95 percent probability that human activities over the past 50 years have warmed our planet.)
- Eight of the ten hottest years on record have occurred in the past decade. It is estimated that each year over 100 billion potential work hours were lost globally to excessive heat. Wildfires are on the rise, as shown in this image from Australia. Extremes of weather are increasingly common, including Tropical storms such as Typhoon Haiyan, driven in part by warming oceans. The ice is melting. This is Greenland where, according to NASA, the ice is melting at a rate of 286 billion tonnes each year.
- The climate emergency may be better described as an environmental emergency. Air pollution is a major problem with the World Health Organisation estimates that 7 million death a year as a consequence. Water pollution of chemicals and plastic waste is increasingly troubling and habitat loss and its inevitable affect on the planets biodiversity is ever increasing.
- In 2008 the UK government, with cross-party consensus, signed the climate change act committing the UK to cut greenhouse gas emissions 80% below 1990 levels by 2050. It has since become apparent that this is not enough and in 2016 the Paris Agreement set a target of “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1·5°C.” The Lancet Countdown is an international collaboration, that monitors climate change, and provides an independent assessment of the delivery of commitments made by governments worldwide under the Paris Agreement. Their latest publication includes: The life of every child born today will be profoundly affected by climate change, with populations around the world increasingly facing extremes of weather, food and water insecurity, changing patterns of infectious disease, and a less certain future. Without accelerated intervention, this new era will come to define the health of people at every stage of their lives. A second path – which limits the global average temperature rise to “well below 2ºC” – is possible, and would transform the health of a child born today. Bold new approaches to policy making, research, and business are needed in order to change course. An unprecedented challenge demands an unprecedented response. In May 2019, the UK government declared an environment and climate emergency and committed to reducing net greenhouse gas emissions to zero by 2050.
- The COVID-19 pandemic has had a significant impact on greenhouse gas emissions. This graph shows the progressive increase in global CO2 emissions with the significant fall in 2020 as a result of COVID-19 and lockdowns. The Global Carbon Project in May estimated a global emissions drop of 3 and 13 % if restrictions continued beyond mid June. It is clear we have our work cut out to achieve net zero.
- So how big a contributor is healthcare? In their 2018 report, the Sustainable Development Unit provided a breakdown of carbon emissions in health and social care in England which contributes approximately 6.3% of the total carbon footprint of England. Here we can see that anaesthetic gases contribute 1.7% of total emissions which is almost the same as staff commuting of the entire 1.3 million workforce. We can also see that patient and visitor travel in yellow are huge contributors. Equipment and pharmaceuticals are the lead contributors.
- The environmental commitments in the NHS Long Term Plan published in January last year include reductions in greenhouse gas emissions through inhalers, transforming anaesthetic practices and improvements to the supply chain. Are you witnessing a ‘transformation in anaesthetic practices’ where you work? If not, why not?
- Desflurane is by far the worst. Work by Sulbaek-Anderson and colleagues found that the 100 year global warming potential of desflurane is 2540 x that of CO2. It is long lived at 14 years
- This graph from Vollmer shows the increasing concentration of these agents in our atmosphere in parts per trillion. The most rapid rate of rise is desflurane, the most persistent of the three.
- I have performed some simple calculations using Tom Pierce’s anaesthetic gases calculator found on the association of anaesthetists website and also the app stores. This is a fairly standard oxygen, nitrous, volatile anaesthetic. With desflurane it produces a whopping 117 kg CO2/hr.
- By reducing fresh gas flow to 1l/min and replacing nitrous with air, significant improvements are made. However desflurane still produces 63 kg CO2e/hr.
- This ultra low flow steady state has some further benefits and sees sevoflurane below 1 kg/hr. Roughly the same as 3 in a car. Of course this does not include priming the circuit or the initial wash-in of anaesthetic agent.
- Jodi Sherman and colleagues performed a life cycle analysis of propofol fixed rate TIVA vs oxygen, nitrous, inhalational anaesthetic in 2012. The top graph shows the total greenhouse gas emissions. The nitrous oxide contribution is double with sevoflurane due to minimum fresh gas flows of 2 litres per minute with sevoflurane in the USA. The below panel considers the life cycle factors excluding atmospheric release of anaesthetic gases. The authors report that propofol is at least 4 orders of magnitude better.
- So what about spinal anaesthesia? Utilising The Gassing Greener App produced by Jodi Sherman and Yale University, I have calculated the CO2e of a very basic spinal. Unfirtunately the calculator has no data on short-acting agents. This gives a flavour of the difference in greenhouse effect which is 4-5 orders of magnitude less than inhalational anaesthesia.
- Predicted environmental concentration PEC Octanol water coefficient Aqautic toxicity studies and fate
- Of course it’s not all about CO2 calculations and global warming. Manufacturing of medical equipment and drug synthesis is resource intensive. Spinal anaesthesia uses less stuff. Fewer syringes, fewer drugs, no pumps or airway equipment. Requirement for medical gases is minimized. It follows that waste is reduced. Here is the waste from a case done by James French under spinal anaesthesia last week. Compare that to your typical GA. Not just the drugs tray but all the airway equipment the anaesthetic assistant usually disposes of. Not all waste is incinerated, around 15% goes to landfill. Furthermore CO2 isn’t the only problem with incineration, air pollution is inevitable. A reduced requirement for PPE has environmental implications Whilst local anaesthetics may be toxic at high concentrations, they do not bioaccumulate in the way that propofol does. Whilst the Environmental Risk Assessments for propofol suggests a low risk, whereas for lidocaine it is insignificant. It is reasonable to expect other LAs to be the same. Spinal anaesthesia may increase the efficiency of lists. If you are able to complete an additional case due to improved speed of turnover there are likely to be significant environmental benefits. Heating or cooling of theatres, lighting, and air flow are all fixed environmental costs. Spinal anaesthesia can facilitate ambulatory surgery in patients who would not be fit for an ambulatory procedure under GA for example those with significant respiratory disease. This almost certainly has environmental benefits including reducing travel of friends and family.
- So what should transforming anaesthetic practices mean. The evidence suggests RA where possible, GA… We must also remember that our chosen technique must facilitate ambulatory surgery and enhanced recovery wherever possible. Prolonged inpatient stays and complications are bad for patients and the environment.
- Spinal anaesthesia may increase the efficiency of lists. If you are able to complete an additional case due to improved speed of turnover there are likely to be significant environmental benefits. Heating or cooling of theatres, lighting, and air flow are all fixed environmental costs. Spinal anaesthesia can facilitate ambulatory surgery in patients who would not be fit for an ambulatory procedure under GA for example those with significant respiratory disease. This almost certainly has environmental benefits including reducing travel of friends and family.
- Maximise ambulatory care Avoid unnecessary airway manipulation & AGPs Preserve critical care medications
- So how big an impact can spinal anaesthesia have? Last month, Kuvadia and colleagues published an article entitled greengional. They explain how at the Hospital for special surgery in new York, where 96% of hips and knees are performed under spinal they have saved 750kg of desflurane and 60 kg of nitrous. This is equated to 26,900 pounds of coal. That’s almost 2million kg of CO2 or 2000 metric tonnes for desflurane alone. We do not know the number of cases that could be safely and effectively done under ambulatory spinal anaesthesia but it’s a lot.