Pure Oxygen May Be Harmful In Emergency
A small study found that a stream of oxygen with some carbon dioxide included may be a better emergency therapy than pure oxygen alone.
SUBSCRIBE TO Science Quickly
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
An ambulance is rushing you to the emergency room, and you’re losing consciousness. The medics grab a facemask and start feeding you a stream of pure oxygen... to cause damage to your brain? A new UCLA brain-imaging study is part of a growing body of research that suggests inhaling pure oxygen is bad for you. The researchers did MRI brain scans of 14 kids, age 8 to 15. In one test they were fed pure oxygen; in the second 95 percent oxygen and 5 percent carbon dioxide.
With pure oxygen the kids’ breathing quickened and blood vessels constricted, preventing oxygen from reaching the brain and heart. Then things got worse. The hypothalamus responded to the emergency signals the body was sending by dumping a massive flood of hormones and neurotransmitters into the bloodstream. Which interfered with the heart’s ability to pump blood and deliver oxygen - the worst thing in a crisis situation. But adding the little shot of carbon dioxide calmed the hypothalamus, the blood vessels relaxed and the surge of dangerous chemicals stopped. Because when it comes to oxygen, you can have too much of a good thing.
It’s Time to Stand Up for Science
If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.
I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.
If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.
In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.
There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.
