By: Alia Hoyt  |  Sep 29, 2020

Fans of television medical dramas usually know what common terms like "code" or "BP" mean. But cyanotic? That one's a little too clinical for laypeople. Once you know the meaning of the word, however, it's easy enough to remember. You see, "cyan" is a specific shade of blue (check the old Crayola box if you want a refresher). "Osis" is the medical term for a specific state or diseased condition. So, cyanosis literally translates to "state of being blue."

While that's fine for a Smurf and all, the rest of us don't want to become cyanotic anytime soon. That's because cyanosis usually is a sign of a serious underlying condition.

"The cause of cyanosis is always a decrease in the amount of oxygen-rich blood," explains Dr. Lisa Moreno-Walton, president of the American Academy of Emergency Medicine in an email. However, lots of issues can cause this decrease, none of them good.

There are two types of cyanosis, Moreno-Walton says. Peripheral cyanosis causes a blue tinge in the fingers, nail beds or even the limbs. Central cyanosis affects the tongue and mucous membranes. "All the things that cause central cyanosis will result in peripheral cyanosis, but all peripheral cyanosis is not the result of central cyanosis," she notes. (If you have darker skin you may notice cyanosis on your lips or nails rather than on your skin.)

There are a lot of things that can affect a person's blood oxygen levels. In order to squash cyanosis, oxygen must first be given to the patient, and then the underlying cause has to be treated. Causes of cyanosis can include:

Cyanosis runs the gamut of being no big deal as long as it's handled, to a sign that something is very, very wrong. But while there are a lot of cyanosis-related variables, one thing is for sure: "All cyanosis should be evaluated by a physician to determine whether or not it is life- or limb-threatening and a course of treatment recommended," says Moreno-Walton.

You can actually tell if blood is fully oxygenated just by looking at it. When everything's normal, blood is bright red. When oxygen levels are low, the blood turns dark purple, or even blue-red in color.

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