• What contribution does anesthesia make to climate change?

     
       

    Daniel Jolley.

    10 articles.

    Created July 17, 2019, last updated 3 months ago.


    Collection: 100, Score: 1394, Trend score: 0, Read count: 1995, Articles count: 10, Created: 2019-07-17 23:56:56 UTC. Updated: 2024-09-14 22:33:52 UTC.

    Notes

    comment
    1

    Also see Carbon Footprint from Anaesthetic gas use [pdf] from the UK’s Sustainable Development Unit.

    Daniel Jolley  Daniel Jolley
     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    Collected Articles

    • Br J Anaesth · Dec 2010

      Inhalation anaesthetics and climate change.

      Although the increasing abundance of CO(2) in our atmosphere is the main driver of the observed climate change, it is the cumulative effect of all forcing agents that dictate the direction and magnitude of the change, and many smaller contributors are also at play. Isoflurane, desflurane, and sevoflurane are widely used inhalation anaesthetics. Emissions of these compounds contribute to radiative forcing of climate change. To quantitatively assess the impact of the anaesthetics on the forcing of climate, detailed information on their properties of heat (infrared, IR) absorption and atmospheric lifetimes are required. ⋯ On the basis of the derived 100 yr GWPs, the average climate impact per anaesthetic procedure at the University of Michigan is the same as the emission of ∼22 kg CO(2). We estimate that the global emissions of inhalation anaesthetics have a climate impact which is comparable with that from the CO(2) emissions from one coal-fired power plant or 1 million passenger cars.

      keep reading… or just mark as read…

    • Br J Anaesth · Dec 2010

      Editorial Comment

      Climate effect of inhaled anaesthetics.

      no abstract available

      read more… mark as read…

    • Anesthesia and analgesia · Jul 2010

      Global warming potential of inhaled anesthetics: application to clinical use.

      Inhaled anesthetics are recognized greenhouse gases. Calculating their relative impact during common clinical usage will allow comparison to each other and to carbon dioxide emissions in general. ⋯ Under comparable and common clinical conditions, desflurane has a greater potential impact on global warming than either isoflurane or sevoflurane. N2O alone produces a sizable greenhouse gas contribution relative to sevoflurane or isoflurane. Additionally, 60% N2O combined with potent inhaled anesthetics to deliver 1 MAC of anesthetic substantially increases the environmental impact of sevoflurane and isoflurane, and decreases that of desflurane. N2O is destructive to the ozone layer as well as possessing GWP; it continues to have impact over a longer timeframe, and may not be an environmentally sound tradeoff for desflurane. From our calculations, avoiding N2O and unnecessarily high fresh gas flow rates can reduce the environmental impact of inhaled anesthetics.

      keep going… or not…

    • Lancet Planet Health · Sep 2017

      Anaesthetic gases, climate change, and sustainable practice.

      no abstract available

      read on… or just mark as read…

    • Anesthesia and analgesia · May 2012

      Editorial Historical Article

      Sustainable anesthesia.

      no abstract available

      read on… mark as read…

    • Anesthesia and analgesia · May 2012

      Managing fresh gas flow to reduce environmental contamination.

      Anesthetic drugs have the potential to contribute to global warming. There is some debate about the overall impact of anesthetic drugs relative to carbon dioxide, but there is no question that practice patterns can limit the degree of environmental contamination. In particular, careful attention to managing fresh gas flow can use anesthetic drugs more efficiently--reducing waste while achieving the same effect on the patient. ⋯ This article provides background information and discusses strategies for managing fresh gas flow during each phase of anesthesia with the goal of reducing waste when using a circle anesthesia system. Monitoring oxygen and anesthetic gas concentrations is essential to implementing these strategies safely and effectively. Future technological advances in anesthetic delivery systems are needed to make it less challenging to manage fresh gas flow.

      expand abstract… mark as read…

    • Anaesthesia · Jul 2019

      Comment Letter

      Desflurane - balancing the environmental costs and cognitive benefits. A reply.

      “Inhalational anaesthetic agents are chlorofluorocarbons, ‘greenhouse gases’ that have between 349 (sevoflurane) and 3714 (desflurane) times the global warming potential over a 20 year time horizon of carbon dioxide (isoflurane 1401), equivalent to driving a car 18 (sevoflurane) to ~350 miles (desflurane) per hour of anaesthetic use (isoflurane 30 miles); these figures do not account for the additional carbon cost of heating desflurane vaporisers. Together with nitrous oxide, inhalational anaesthetic agents contribute ~2.5% of the 22.8 million tonnes of carbon dioxide equivalents the NHS produces annually.” - White

      summary

      explore further… or not…

    • Nature · Oct 2020

      A comprehensive quantification of global nitrous oxide sources and sinks.

      Nitrous oxide (N2O), like carbon dioxide, is a long-lived greenhouse gas that accumulates in the atmosphere. Over the past 150 years, increasing atmospheric N2O concentrations have contributed to stratospheric ozone depletion1 and climate change2, with the current rate of increase estimated at 2 per cent per decade. Existing national inventories do not provide a full picture of N2O emissions, owing to their omission of natural sources and limitations in methodology for attributing anthropogenic sources. ⋯ Our findings point to growing N2O emissions in emerging economies-particularly Brazil, China and India. Analysis of process-based model estimates reveals an emerging N2O-climate feedback resulting from interactions between nitrogen additions and climate change. The recent growth in N2O emissions exceeds some of the highest projected emission scenarios3,4, underscoring the urgency to mitigate N2O emissions.

      read on… mark as read…

    • Health trends · Jan 1991

      The contribution of medical nitrous oxide to the greenhouse effect.

      Nitrous oxide is now recognised as an important contributor to the 'greenhouse' effect. Each year the medical profession unwittingly adds a very small burden of this gas to the atmosphere. Unfortunately, the long lifetime of nitrous oxide means that all emissions into the atmosphere are significant. By making small changes in their practices, anaesthetists are well-placed to help reduce the potential environmental damage.

      read more… or just mark as read…

    • Anaesthesia · Mar 2024

      Review

      The science of climate change and the effect of anaesthetic gas emissions.

      Global Warming Potential vs Radiative Forcing

      Global warming potential is "...the ratio of the cumulative radiative forcing (the energy being added to the planet, based on radiative efficiency and lifetime) over a time horizon from the instantaneous release of 1 kg of a given gas, such as desflurane, relative to that of 1 kg of carbon dioxide." A 100 year time horizon is commonly used as GWP100, reflecting the long lifetime of CO2, representing the warming potential of a single emission of a gas compared to the same mass of CO2. GWP is then used to derive CO2-equivalents.

      Although GWP allows a simplistic comparison of greenhouse gases (eg. desflurane GWP 2530), it is misleading to use it to assess the climate impact of volatile anaesthetic agents primarily because of their short lifetimes, but also because "GWP does not consider the actual atmospheric abundance of a greenhouse gas, nor does it represent any of the physical complexity of the overall climate system..."

      "Based on climate science, we assert that this is a physically unsound approach for determining the potential climate impact of volatile anaesthetic gases, and that it is the atmospheric concentration and radiative forcing of individual greenhouse gases that matter..." – Slingo & Slingo.

      Instead climate scientists today prefer to use radiative forcing, "... the difference between the energy entering the planet and the energy leaving it..."

      The percentage contribution of all volatile anaesthetic gases to radiative forcing is <0.01% compared to that from carbon dioxide. In comparison, the global emission reductions due to the COVID-19 lockdown were almost 1000x greater than the cumulative impact from anaesthetic volatile gases, and yet this reduction was undetectable above normal climate variability.

      Atmospheric concentration (ppt) Atmospheric lifetime (y) (Effective) radiative forcing (Wm-2)
      Carbon dioxide 420,000,000 100+ 2.16
      Methane 1,920,000 12.4 0.54
      Nitrous oxide 336,000 123 0.21
      Desflurane 0.37 14.1 0.00017
      Sevoflurane 0.16 1.4 0.00003
      Isoflurane 0.11 3.5 0.00006

      "On the basis of GWP, anaesthetic gases appear to be very 'damaging'. However, this conclusion is scientifically unsound: their lifetimes are short; their emissions, accumulation and resulting atmospheric concentrations are minute; and their actual radiative forcing is vanishingly small."

      More complexity...

      Beyond the over-simplification of GWP and CO2e, Slingo & Slingo also explore the challenge in linking the minute radiative forcing of volatile anaesthetic gases to actual climate change and impact.

      "...future warming will be determined by how successful we are in controlling our direct carbon dioxide emissions. ... While changing a vaporiser feels achievable and tangible, the scientific reality is inconsequential when we consider all the steps from GWP to climate impact. ... It is carbon dioxide emissions that will define our future, not the use of volatile anaesthetic agents."

      summary

      read more… mark as read…

    collapse collection…


What will the 'Medical Journal of You' look like?

Start your free 21 day trial now.

We guarantee your privacy. Your email address will not be shared.