Day 2 – How do anesthetics contribute to global warming? Learning the physics and chemistry of anesthetics in clinical settings

Green Anesthesia – Stanford Day 2 – How do anesthetics contribute to global warming? Learning the physics and chemistry of anesthetics in clinical settings

Key Takeaways

‘Atmospheric Layers and Energy Balance: Earth’s atmosphere is composed of several layers, notably the troposphere and stratosphere. Understanding these layers is crucial because they play a significant role in the climate system, particularly in how Earth absorbs solar radiation and re-emits it as infrared radiation.
Impact of Anesthetic Gases: Specific anesthetic gases, including chlorofluorocarbons and other gases used internationally, absorb outgoing infrared radiation. This absorption disrupts Earth’s ability to cool itself, directly contributing to global warming.
Rise in Greenhouse Gas Concentrations: Since the Industrial Revolution, there has been a significant increase in the concentrations of greenhouse gases such as CO2 and nitrous oxide. Anesthetic gases, though present in smaller amounts, are potent greenhouse gases and their concentrations have also been rising.
Global Warming Potential (GWP): Anesthetic gases have varying GWPs, which measure their ability to trap heat in the atmosphere compared to CO2. These GWPs provide a standardized way to assess and compare the impact of different gases on global warming.
Urgent Need for Sustainable Practices: The increasing use of anesthetic gases poses a significant risk of enhancing the greenhouse effect. It is imperative for the healthcare sector to adopt more sustainable practices, including using anesthetics with lower GWPs, improving the efficiency of anesthetic delivery systems, and implementing gas capture technologies to reduce emissions.

How Anesthetic Gases Contribute to Global Warming

Introduction to Earth’s Atmosphere

The Earth is surrounded by layers of atmosphere, with the troposphere extending up to 10 kilometers and the stratosphere up to 50 kilometers. The stratosphere contains the ozone layer, critical for protecting life from the sun’s harmful ultraviolet radiation. The troposphere contains most of the water vapor. These layers play essential roles in our climate and environmental systems.

Energy Balance and Radiation

Earth aims to maintain an energy-neutral state, receiving about 342 watts per meter squared of solar radiation. About one-third of this radiation is reflected back into space, while two-thirds are absorbed and re-emitted as infrared radiation. This radiation spreads across wavelengths from 3 to 70 micrometers, peaking around 10 micrometers.

The Role of Anesthetic Gases in Global Warming

Anesthetic gases like chlorofluorocarbons and other internationally used gases absorb outgoing infrared radiation. By doing so, they prevent Earth from cooling effectively, contributing to global warming. This section of the video highlights how specific anesthetic gases trap heat in the atmosphere, enhancing the greenhouse effect.

Increasing Levels of Greenhouse Gases

Since the Industrial Revolution, the concentration of CO2 has increased from 280 to 400 parts per million, and nitrous oxide from 270 to 320 parts per billion. Fluorocarbons, undetectable before 1953, are now measured in significant quantities. These gases significantly contribute to the global greenhouse effect, necessitating a measure known as carbon dioxide equivalence to compare their impacts based on their global warming potential.

Global Impact and Research

Studies have shown that even remote parts of the planet contain detectable levels of inhalational anesthetic gases, indicating their widespread environmental penetration. The video discusses research findings that measure the global warming potential of these gases, their atmospheric lifetimes, and their overall impact on climate change.

Future Projections and Models

Projections based on different consumption scenarios show significant potential increases in radiative forcing, a measure of how much these gases could further warm the Earth. The video explains different modeling scenarios that predict how continued or increased use of anesthetic gases could exacerbate global warming.

Conclusion: An Urgent Call for Change

The video concludes with a strong message on the need for the medical community to consider the environmental impact of anesthetic gases. It calls for reducing the use of high global warming potential anesthetics and adopting sustainable practices to mitigate their adverse effects on climate.

Quizzes

Quiz: Day 2 – How Do Anesthetics Contribute to Global Warming?

Previous Lesson

Back to Course

Next Lesson

Green Anesthesia – Stanford