Why it matters (facts & figures) | Association of Anaesthetists
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Why it matters (facts & figures)

Why it matters (facts & figures)

  • The NHS produces 3% of all UK carbon dioxide emissions. 2015 data showed that the NHS carbon footprint in England is  22.8 million tonnes of CO2 equivalents and has seen a reduction of 11% between 2007-2015
  • Inhalation anaesthetics, such as nitrous oxide, isoflurane, desflurane, and sevoflurane are greenhouse gases and contribute to climate change. These medical gases account for 5% of the carbon dioxide equivalence emissions of acute NHS hospitals
  • The relative contribution of a greenhouse gas towards global warming may be described by a number of methods. The most frequently reported relating to anaesthesia is the Global Warming Potential, or GWP, which is a measure of the relative contribution of mass of inhalational anaesthetic agents (IAA) to an equivalent mass of CO2
  • As the global warming effect of IAAs decreases over time due to atmospheric/UV degradation, GWPs are usually appended by a number indicating the GWP over a time period in years
  • The GWPs of the inhalational agents can be seen in the table below:
  Atmospheric lifetime (years)  GWP100
Sevoflurane  1.1 130 
Isoflurane 3.2 510
Desflurane 14 2540
Nitrous Oxide 110  298
  • The global warming effects of IAAs may be ameliorated through use of low-flow anaesthesia, , choice of volatile agents with lower GWPs and minimising the use of nitrous oxide.  Technologies for capture of scavenged gases are also currently in evolution 
  • You can download an anaesthetic gases calculator here
  • The NHS produced just less than 590,000 tonnes of waste in 2016/17 representing around 2% of all industrial and commercial waste in England
  • Each operating theatre produces around 2300Kg anaesthetics waste and 230Kg sharps waste per annum, approximately 40% of which could be reclassified as domestic waste or recycling with significant environmental and financial benefits.