text: Anaesthetic gases used to send patients to sleep during surgery are accumulating in the Earth's atmosphere where they are contributing to climate change. Scientists say they have detected the gases used in anaesthetic as far a field as Antarctica and concentrations have been rising globally in the past decade. The gases - desflurane, isoflurane and sevoflurane - are potent greenhouse gases that have 2,500 times the impact on global warming compared to carbon dioxide. Anaesthetic is used to send patients to sleep during surgery (above) but it may also be warming the planet . Atmospheric scientists who have been monitoring the gases say that while the concentrations in the atmosphere are low, they are having an increasing effect on the climate. Dr Martin Vollmer, who led the study at the Swiss Federal Laboratories for Material Science and Technology in Dubendorf, Switzerland, said the anaesthetic gases were capable of storing far more energy from the sun than carbon dioxide. The world needs to prepare itself for a rapid increase in the speed of climate change, scientists have warned. Researchers have found evidence that suggests the rate at which temperatures are rising in the northern hemisphere could be 0.25°C per decade by 2020 - a level not seen for at least 1,000 years. The analysis, based on a combination of data from more than two dozen climate simulation models from around the world, looked at the rate of change in 40-year long time spans. Over the 900 years preceding the 20th century, 40-year warming trends rarely showed an average rate much higher than 0.1°C per decade, the study found. But by 2020 the rate was expected to have risen to an average of 0.25°C per decade, give or take 0.05°C. Different scenarios of future emissions showed that even at the lower end of greenhouse gas generation climate change picked up speed in the next 40 years. He said: 'On a kilogram-per-kilogram basis, it's so much more poten . 'Modern halogenated inhalation anesthetics undergo little metabolisation during clinical application and evaporate almost completely to the atmosphere.' The researchers, whose work is published in the journal Geophysical Research Letters, found that concentrations of desflurane reached 0.30 parts per trillion in 2014. Isoflurane, sevoflurane and halothane have reached 0.097, 0.13 and 0.0092 parts per trillion in the atmosphere respectively. By comparison, carbon dioxide gas currently makes up 400 parts per million in the atmosphere. However, one kilogram (2.2lbs) of desflurane produces the same greenhouse effect as 2,500 kg (5,512lbs) of carbon dioxide. The researchers estimate that anaesthetic gas emissions currently combine to produce the equivalent effect in the atmosphere of 3.1 million tonnes of carbon dioxide. The research team did not examine the impact of nitrous oxide, another major component of anaesthetic, as it is released by many other sources. The researchers have been taking air samples from remote sites around the Northern Hemisphere since 2000 while they have also obtained air samples in the North Pacific and the South Shetland Islands in Antarctic. The gases escape through vents in operating rooms (pictured) when breathed out by patients and from masks . The team also used two hourly measurements at a high altitude observatory at Jungfraujoch, Switzerland since 2013 to track anaesthetic gases. They then used computer modelling to produce global estimates for the concentrations of these gases. The gases escape from hospital operating rooms via air vents during surgery. An estimated 280 tonnes of anaesthetic gases are used every year. Jodi Sherman, an anaesthesiologist at Yale University who reviewed the paper, said hospitals should consider using other chemicals in anaesthetic. She said: 'There's nothing unique about desflurane that we can't do with other drugs. 'Desflurane we could live without, and every little bit makes a difference. 'Health care in and of itself in the US is one of the worst polluting industries. Scientists say that hospitals should consider alternative anaesthetics when performing operations like above . 'It generates eight percent of US greenhouse gases according to one study. 'Add to this the fact that climate change has been recognized by the World Health Organization as the number one health issue of the 21st century, and it behooves us to do a better job with emissions.' However, Edmond Eger, an anaethesiologist at the University of California San Francisco, said: 'What the report fails to note is that a major factor determining the environmental effect is the manner in which the anesthetics are used. 'Many anesthetists deliver sevoflurane or isoflurane in a two - three liters per minute flow but deliver desflurane in a lower flow - 0.5 to one liter per minute. 'Some believe that desflurane has clinical advantages that argue for its continued use.'
target: Gases used in anaesthetic in are accumulating in the Earth's atmopshere .
  The gases - desflurane, isoflurane and sevoflurane - have a greenhouse effect that is 2,500 times more potent than carbon dioxide, say scientists .
  New study finds their concentrations are relatively low but are increasing .
  Scientists urge hospitals to find more environmentally friendly alternatives .