First Aid for Oxygen Deprivation

Here’s a fun new word to impress your friends at parties: hypoxia. Medical professionals and other Latin speakers will recognize it as a fancy way to describe oxygen deprivation, which is a pretty broad class of conditions. Hypoxia can be general or localized (i.e., affecting just a hand), can result from anything from asthma to cancer, and favors no particular demographic. What are the symptoms of hypoxia?

• headache
• nausea
• feeling of euphoria
• fatigue
• shortness of breath

So, when might the average, mostly-healthy person experience oxygen deprivation? Here are a few instances: 1. Choking. Pretty straightforward: a blockage in the windpipe prevents the intake of oxygen, cutting off the supply to the lungs. Under-oxygenated blood appears blue under the skin (called cyanosis, in case you need another big word), but the more pressing danger is the oxygen-deprived brain, which is susceptible to long-term damage. The only safe way out of that situation is to take care of the object that’s preventing you from breathing. Sarah’s post on choking tells you how to rescue someone else, or how to perform the Heimlich on yourself if rescuers are scarce. 2. Altitude. Well do I remember my years of travel between my Pacific Northwest home base and my university in the Rocky Mountains. Every time I left sea level, I could expect a day of headaches and catching my breath. (Oh, how I hated those hills leading up to campus!) In its more acute form, hikers refer to this kind of hypoxia as altitude sickness, or mountain sickness. The less oxygen-dense air at higher altitudes deprives lungs—and, consequently, brain, blood, muscles, etc.—of critical oxygen, causing everything from nausea, lightheadedness, and nosebleeds to swollen hands and feet, drowsiness, or an accelerated pulse. Just as dangerous as either of the previous instances, altitude-related hypoxia can only be reversed by increasing oxygen intake. In most cases, that means you’ll need to head down the mountain. You can lower your risk in the first place by ascending slowly, exerting yourself less at higher altitudes, or—assuming you’re braver than I am and are hiking something really, really high—carrying supplemental oxygen with you.

Another situation where the altitude and air pressure could lead to oxygen deprivation is on an airplane. If the cabin suddenly loses air pressure, masks will fall and will provide you with the necessary oxygen. However, the cabin could also lose air pressure over time because of a leak, in which case the symptoms will build up slowly and you may not notice them. 3. Smoke inhalation. While you may go through the motions of breathing, inhaling something other than oxygen—like fumes from a house or forest fire—decreases your O₂ levels and puts you at risk of hypoxia. And in a situation where environmental oxygen is scarce, your body’s response can put you in even greater danger: the lethargy and disorientation that results from withholding oxygen from the brain can make it difficult to get yourself quickly out of danger; and hyperventilation, meant to increase oxygen intake, only speeds up the intake of noxious fumes. Here, as with most emergency issues, your best bet is prevention, and common sense is a close second. Smoke alarms and fire extinguishers are your friends. Keep an eye on city’s posted fire danger levels. Asthmatics especially should keep medicines and inhalers current and should be careful of outdoor activity during wildfire season. Now, if you want to sound really erudite at this party, you could differentiate between hypoxemic hypoxia and cerebral hypoxia…or maybe just stick to that cool story of how you almost summited Annapurna.