gonna do a lil thread about how to use one of these properly since it's not necessarily the most intuitive thing. i'm an EMT who's treated lots of COVID patients in NYC since mid march.

(nothing i say should be treated as a substitute for legit research or a doctor's opinion) https://twitter.com/KarenAttiah/status/1328705567746109441

firstly you need to know the baseline oxygen level for whoever you're checking. figure out what's normal for you and your loved ones when in a comfortable, resting state. take into account any history of breathing conditions like asthma, COPD, etc.

healthy people should usually be "satting" at or above 97%. people with resp issues may be a little lower. when someone is consistently below 93% or so, I start to be concerned. if someone is satting that low with high fever, that's serious and you should go to the ER. THAT SAID-

-- Pulse oximeters can be janky, especially for elderly people with very cold, bony fingers, or conditions like diabetes! you may have trouble getting a reading at all on some people. and don't freak out if you get a very low reading at first --

-- if you have the oximeter mispositioned, or the patient just has really "bad" fingers, you can get an initial reading that's like crazy low. don't panic if this happens, just try again! oximeters can be inaccurately low, but it's pretty tough for them to be inaccurately high.

use common sense -- in my working experience, people who have oxygen saturations below 85% or so are usually quite obviously in serious trouble. if your loved one is sitting there, talking to you clear as day and feeling fine, but the oximeter is reading 50%, that's not accurate.

also common sense: do not delay seeking medical attention just because the oximeter is reading high. if you or someone else experiences serious difficulty breathing, get help ASAP. you know what's up with you and yours better than a $15 piece of plastic or some dork from twitter.

addendum: upon thinking about it harder, 93% is probably a little too low to start showing alarm. 95% would probably be a better "oh no" number for laypeople -- i tend to see patients who already have a lot of chronic health problems so lower saturations are more common for me.

my thinking here is that, people in the medical field have a better ability to correctly look at a low reading and say "that's not so bad given the circumstances". you, sitting at home, should be a little more cautious if that makes sense.

WOW i got a big freaking huge quote tweet off of this!! Didn't expect this to be seen by more than my friends! I stand by everything i said here, but i encourage you to read more from actual medical sources if you plan to use a pulse oximeter on yourself and others!