Heat Exhaustion and Heat Stroke
It's a hot weekend here in the Pacific Northwest. Well, hot for us. With summer approaching in the northern hemisphere, it will likely get even warmer in the coming weeks. So it seems like a good time to discuss a very important subject.
First off, the topic this week isn't germane to photography per se, but it is one that that photographers are susceptible to, or at least those of us that predominantly practice our craft in the great outdoors. And it's one that can be especially important if you tend to head out on your own on occasion, relying on your own experience and ability to keep yourself safe. Getting in touch with nature can be enjoyable, but nature can also be harsh at times — even dangerous. Only daredevil photographers would go out chasing tornados or other extreme weather events, but few would think twice about heading out on a warm summer day.
And yet we all know that heat can be dangerous. One of the early lessons every child learns is that the kitchen stove can be hot, and it can burn you. You don't have to be in the kitchen to get burned of course. The hot sun can cause sunburn, and often you won't be aware of it until it's too late. Over the years, I've had to learn that I sunburn easily, and so I take precautions. As a kid, I used to get sunburned badly at least once most every summer. Painful, blistering skin has a way of teaching a lesson. The sun is hot, and it can burn you. These days, I make darned sure that I have good sunscreen with me, and that I use it. I know that when covered in a good SPF 40 or better sunblock I'm fine. If I get too wrapped up in photographing the sunrise and forget to apply sunscreen though, I'll regret it. Being prepared keeps me safe. It's part of what I need to do to be safe in the outdoors. Those of you who are prone to sunburn know what I'm talking about.
But as the earth slowly tilts on its axis so that the hemisphere where you live faces increasingly towards that sun — the season we call summer — there are health risks that sunscreen can't protect you from. The risk isn't just from getting burned. It's also simply from getting too hot, and for too long. Heat-related illnesses aren't something to be taken lightly.
Internal body temperature for us humans is around 98.6 degrees Fahrenheit. Our bodies are built with strategies to maintain that temperature. That is to say, we are warm blooded animals. When it gets too cold, we shiver to help burn calories and warm up. In extreme cold, the blood vessels in our extremities will constrict so that core body temperature can be better maintained. When it gets too warm, we sweat to provide for evaporative cooling. We wear t-shirts and shorts to avoid blocking that process. We move a little more slowly and take it easy. We drink cold liquids to help cool off from the inside.
But there are limits. And if we don't pay sufficient attention to the problem and take steps to mitigate the effects, we can reach those limits more quickly.
Heat exhaustion happens when your body gets too hot for your warm blooded coping mechanisms to handle. It can result from hot weather, from physical exertion, or from a combination of factors. Regardless, the net effect is the same. You will find yourself sweating more and more. Even when drenched in sweat, your skin will feel cool to the touch. You may develop a nasty headache or feel nauseous. You will almost certainly feel tired and in need of rest. You will become progressively dehydrated and thirsty if you don't take in enough fluids. All that sweat has to come from somewhere. High humidity can exacerbate the problem as it makes it difficult for sweating to effectively cool the body.
If you find yourself in this predicament, it's important to get out of the heat or to cool off in some way. Unfortunately, heat exhaustion can also impair your ability to think clearly, so you may not realize what's happening, at least at first. Just like with my sunburn problem as a kid, the effects of heat exhaustion can sneak up on you. Even if you do feel as if something is wrong, it may not be clear to you exactly what is going on. Knowing about the dangers and symptoms ahead of time will hopefully help you recognize them should they occur.
Even once you do get out of the heat, it can take some time for the body to cool off. But if you're not starting to feel better within a half hour or so, seek medical help.
Our warm blooded temperature regulating mechanisms begin to shut down and fail if the body gets even hotter. Once body temperature reaches around 104 degrees, heat stroke sets in. And heat stroke can be very serious indeed. Rather than sweating profusely, the body will actually stop sweating. Rather than the skin feeling clammy and cool from sweating, it will become red, hot, and dry to the touch. Your faint headache will become quite pronounced and throbbing. Your nausea will get worse, and vomiting may result. Your heart rate will be noticeably fast, even when you're no longer exerting yourself. Eventually, you may lose consciousness. As I say, very serious indeed. I doubt any of us carry a rectal thermometer to check if our core temperature gets up to 104, so you may not realize just how hot you are. And few of us want to admit they need help, even under the best of situations, especially when they are preoccupied with a pursuit they enjoy such as photography.
If you do suspect that you or someone you are with is suffering from heat stroke, urgent medical help is needed. Call 9-1-1. Take immediate steps to cool them off. Keep in mind that one of the symptoms of heat-related illness is confusion, so self-diagnoses may difficult. Also, heat stroke can actually occur without preceding heat exhaustion. Or at least not recognized heat exhaustion. Your best course of action is to prevent heat stroke, not to have to treat for it.
The temperature here in the Pacific Northwest doesn't often get above 100, but it can happen. Today's high is predicted to be in the mid-90's. But keep in mind that carrying around a pack loaded with camera gear, or even hiking down a trail with a lighter pack can contribute to the problem. Any activity that burns a significant amount of calories can. So don't discount the need to be aware of the dangers just because you may not live in the desert southwest.