Is More Oxygen Better?

If the p o two is ow, dispite an adequate saturation reading, seeing the pulse oximeter is not accurate, you can turn up the f i o two. Anden conversely, if the po two is high, more than about a hundred or so,you can turn down the f i O Two. So why would you ever turn down thef i 2? Some people outher might be thinking, isn't more oxygen better? We've known for a long time actually, that oxygen can be injurious to the lungs,. You get hyper oxic lung injury. In fact, if you put a mouse in a hundred % oxygen tey'll live for about three to five