July 27, 2006
Posted by Jim Macdonald at 03:33 PM * 200 comments
Welcome back to Environmental Emergencies Theatre. In our last thrilling episode we saw Hypothermia.
It’s summertime now, so it’s time to talk about Heat Stress, aka Hyperthermia. Hyperthermia, like her twin sister Hypo, can kill you deader’n dirt by this time tomorrow.
We do best when our core temperature is within one degree either way of 98.6 degrees Fahrenheit (37 degrees Celsius). Below that, you’re into hypothermia. Above it, you have hyperthermia.
We generate heat all the time (the fancy name for this is “thermogenesis”) via three basic means. One is thermoregulatory thermogenesis, which is the endocrine system and the central nervous system working together to control the rate of cellular metabolism. The second kind is work-related thermogenesis: when the skeletal muscles contract, they throw off heat as a byproduct. The third kind is diet-related thermogenesis: heat generated by chemical bonds being broken, and complex sugars and proteins being reduced to simpler molecules, as we digest our food.
The name for keeping the interior environment of our body within certain narrow limits (pH, salinity, and so on) is homeostasis. The human body has several systems that are tasked with maintaining our internal temperature. It’s a mammal thing. We regulate our internal temperature by internal means so we don’t have to crawl into cracks or sun ourselves on rocks.
Regardless of the exact origin of the heat in the body, it has to go somewhere, because the body is very heat-sensitive. Even when it’s forty below and we’re wearing our parkas, we still need to bleed off excess heat. All we’re doing is controlling the rate. If the core body temperature hits around 105 degrees Fahrenheit, the proteins in the brain start to denature, and within ten to fifteen minutes … you’re in deep, deep trouble.
Convection is carrying away heat through the motion of a fluid over a surface (the fluid is warmed, expands, rises, and is replaced with cooler fluid). Conduction is carrying away heat through direct contact with a cooler object. Radiation is the direct loss of heat as infrared radiation. And evaporative cooling is using the latent heat of evaporation to cool things — it takes energy to move water from its liquid form to its vapor form at the same temperature.
As the core temperature of the body rises, the hypothalamus (it’s under the thalamus at the base of the brain) senses the rise both directly from the blood that’s moving by it, and remotely from temperatures sensors in the extremities and in the great vessels in the chest. The hypothalamus stops producing the hormones that stimulate cellular metabolism, and instead starts dilating the blood vessels (vasodilation) near the surface of the skin and stimulating perspiration.
The skin grows flushed, and wet. With the vasodilation in the skin and subcutaneous tissues, the skin gets hotter, which leads to more convective cooling and radiant cooling. The sweat evaporates, carrying away heat as liquid turns to vapor. The newly-cooled blood goes back into the core. All’s well.
That’s if things are working right.
The very young and the very old have a harder time dealing with heat stress. They have less-responsive thermoregulating systems, and have a lower tolerance to variations in core temperature. Folks with diabetes may have suffered damage to the parts of the autonomic nervous system that provide feedback to the hypothalamus, and may have nervous system damage that interfers with vasodilation and sweating. Some drugs, notably diuretics, beta blockers, and vasopressors, interfere with vasodilation and sweating. Antihistamines, and some psychotropics, can interfere with the central nervous system’s thermoregulation.
High humidity can interfere with evaporative cooling. High environmental temperatures and lack of ventilation can interfere with convective and radiant cooling. High heat, high humidity, and poor ventilation is the trifecta. Make it an elderly diabetic in a non-air-conditioned apartment where the windows don’t open, and it’s 9-1-1 time.
So, we’re now in the Land of When Things Go Wrong.
First up is heat cramps. The main causes of heat cramps are dehydration and loss of electrolytes (especially sodium). Sweat not only takes water out of the body, it takes out salt. You usually see heat cramps in folks who are working in a hot environment: work-related thermogenesis leading to vasodilation and sweating, leading to dehydration and hyponatremia. Heat cramps usually show up in the extremities (especially legs) and abdomen. This is nature’s way of telling you to stop exercising when it’s that hot out.
What to do about it: get out of the hot environment, stop using your large muscles, drink water, replace electrolytes.
Next up: Heat exhaustion (AKA heat prostration and heat collapse). This is the most common heat-related injury, and its basic mechanism is the same as heat cramps. The basic causes are heat exposure, stress, and fatigue. (It doesn’t have to be particularly hot before heat exhaustion is a possibility — wearing multiple layers of clothing that limit the effectiveness of sweating will do the job just fine. So, if you’re out hiking, take off layers; when you stop to rest, put on layers.)
The signs and symptoms of heat exhaustion are:
- Dizziness, weakness, fainting, nausea, and headache.
- Onset while working in a high heat/high humidity/poor ventilation environment and sweating heavily. Infants, the elderly, and the unacclimatized may experience onset at rest.
- Cold, clammy, skin; ashen pallor.
- Dry tongue; thirst.
- Vital signs within normal limits, although the pulse may be rapid and the diastolic blood pressure (that’s the bottom number; the pressure when the heart isn’t contracting) may be low.
- Normal or slightly elevated body temperature.
What to do about all this: Take off any excessive layers of clothing, particularly around the head and neck. Get out of the hot environment (say, into the back of a nice air-conditioned ambulance). Drink a liter or so of water (slowly, so nausea doesn’t develop). Loosen restrictive clothing, lie down with your feet up, and use a fan for cooling.
Usually the symptoms resolve within a half hour. You should get worried if the symptoms don’t start to resolve, if the core temperature stays elevated or increases, or if the patient starts to lose consciousness. Be very cautious with the very young, the very old, and folks with underlying medical conditions (e.g. diabetes, heart disease).
Heat exhaustion, like heat cramps, is caused by dehydration and loss of electrolytes.
Like heat cramps, heat exhaustion is nature’s way of telling you to slow down.
Now comes the biggie: Heat stroke. This one will kill you, and kill you fast. When your brain is gone it’s game over, and that can take as little as ten to fifteen minutes from onset of symptoms.
In heat stroke your body has essentially given up on cooling. The hypothalamus is saying “See ya later.”
This is the one that kills kids who are locked in cars on sunny days. It kills old folks in poorly ventilated apartments during heat waves. It kills healthy thirty-year-old guys who are working in humid warehouses. It kills.
Most of your heatstroke patients aren’t sweating — the sweating mechanism has been overwhelmed. You may find ‘em with wet skins, though — because the sweat that was there before hasn’t dried off. Wipe ‘em down with a towel — if no new sweat forms, be very suspicious. The patient can be going into heat stroke even if the sweat is still pouring off him. The main thing is the core temperature: 105, 106, higher.
Signs and symptoms:
- High body temperature.
- Decreased level of consciousness.
- Change in behavior.
- Not sweating in a hot environment.
- Skin may be red or pale, depending on whether vasodilation has shut down yet.
- Signs of shock: elevated heart rate and breathing; decreased blood pressure.
Not all of these signs and symptoms will be present in every case.
This one is a medical emergency. You have to act, right now. Your first and biggest objective is to lower the core temperature, and do it by any means available.
- Move the person out of the hot environment.
- Set air conditioning to maximum.
- Remove the patient’s clothing.
- Put cold packs on neck, armpits, groin.
- Cover the patient with wet sheets or towels, or spray a mist of water on him.
- Aggressively fan the patient, even if you can’t dampen the skin.
- While all this is going on, be on the phone to 9-1-1. Even if you save the brain you may not have saved the kidneys. This person needs to be in a hospital.
One minor caveat: Try not to put the patient into hypothermia. If he starts shivering he’s just going to build body temperature back up.
Death is nature’s way of telling you to slow down.
Prevention, Ounce of
Stay out of high heat/high humidity environments, particularly if you aren’t acclimated to them. Shopping malls, office buildings, movie theaters, are all air conditioned. Try to be in one of them during the heat of the day. Crank your home air conditioning to 70 or lower. If you must be in a high heat/high humidity environment, try to limit your exposure to three hours or less.
But the worst o’ your foes is the sun over’ead:
You must wear your ‘elmet for all that is said:
If ‘e finds you uncovered ‘e’ll knock you down dead,
An’ you’ll die like a fool of a soldier.
—Rudyard Kipling
Wearing a hat is the simplest thing you can do if you must be out-of-doors in a heat-stress environment. Without a hat the only things between your brain and a 10,000 degree thermonuclear furnace are a layer of thin bone, a layer of thin scalp, and a (perhaps thinning) layer of hair. Carrying an umbrella or parasol isn’t a bad idea. Wear light-colored, loose-fitting, cotton clothing. Remove layers as necessary to allow sweat to dry on your skin.
A cool neck wrap, to keep the brain cool, can sometimes help (if the humidity is low enough to allow evaporation.
Try to avoid heavy meals (diet-related thermogenesis) and heavy physical labor (work-related thermogenesis) when it’s hot and humid. The siesta is a wonderful idea. So’s having the major meal of the day well after sundown.
Hydration. Water is your friend. How much water? Just like with hypothermia, drink water until your urine is frequent, copious, and clear. Drink water even if you aren’t thirsty. Line up eight to twelve half-liter bottles of water on your desk and drink one of them at the top of every hour.
This brings us to the subject of Water Intoxication. Every year you lose a frat pledge or two from this — being forced to drink large amounts of water over short periods. What happens is the electrolytes get washed out of the body, and Bad Stuff (like cardiac arrythmias) follow. So, drink your water over long periods of time, and keep up your salt intake. Pretzels, potato chips, lemonade, watermelon, bananas … but not salt pills. (Salt pills can rip your stomach and can send you into hypernatremia, which has its own constellation of not-fun signs and symptoms.)
As always, I am not a doctor and can neither diagnose nor prescribe. Nothing here is advice for your particular condition; it is presented for amusement only.
Please stay safe.
Copyright © 2006 by James D. Macdonald.
I am not a physician. I can neither diagnose nor prescribe. This post is presented for entertainment purposes only. Nothing here is meant to be advice for your particular condition or situation.
Heat Stress by
James D. Macdonald is licensed under a
Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.
(Attribution URL: http://nielsenhayden.com/makinglight/archives/007766.html)
Index to Medical Posts
Jim, I teach classes in heat stress and heat related illnesses for the American Red Cross. Your article is SPOT ON... Everyone needs this info. Print it. Copy it. Distribute it. We all remember the Chicago heat wave a few years back... Thanks for posting this!!!
If you have a hot water bottle - they can be filled with cold water as well as hot. Or crushed ice with water, which is what I had in the one that was keeping my neck cool on Saturday night, when it was still in the high 30s Celcius in the house in the middle of the night.
Jim --
Good post, thanks. I did want to operationalize a definition, though: broadly speaking, what is the bell curve of 'very young'? 'Very old', I think I've got a handle on; as a parent it's the other end of the spectrum that concerns me now ;-)
Thanks Jim. I had a nasty run-in with heat exhaustion a couple of years ago at a baseball game. Luckily we were at a modern stadium with a/c in the concourses and I have a husband who knows that ashen and disoriented is a very worrying way for his normally ruddy-cheeked, sharply opinionated wife to be.
I was an Army medic in the California ARNG and my main job was preventing heat casualties. More tips:
1. If you are working in hot conditions and you feel thirsty, it is almost too late. You need to stop working and drink two quarts of water. When it's really hot, your body can't tell you quickly enough that you need water. I've seen guys collapse from heat exhaustion who never felt the least bit thirsty. You need to drink a minimum of 1 quart an hour. A great way to know if you are drinking enough water is that your pee should be clear. If your pee is yellow, drink more water, even if you're not thirsty.
2. Alcohol and sugar are very bad in hot weather. Resist the urge for a cool beer or a soda. Drink water. Alcohol especially speeds dehydration.
3. Sunscreen. Use it, lots of it.
4. History of heat injury. If you've ever suffered from heat exhaustion, you become much more likely to suffer from it again. We never knew why, but once a guy fell out from heat exhaustion, it usually happened again under even less sever circumstances. You become more vulnerable to heat injury after you have suffered heat exhaustion.
5. Salt tablets. They don't work. As Jim said, get your salt by putting it on your food.
This, like the hypothermia one, is great. There are a couple of typos in it: 'several sytems', 'dryed', 'suspiscious', 'the only things between your brain and a 10,000 degree thermonuclear furnace is' (should be 'are').
Ordinarily I wouldn't inspect something so closely. But when something's this good I just naturally want it to be perfect.
Re: the hot water bottle with ice in it--
anything chilled applied to parts of the body where there are a lot of blood vessels and not a lot of insulating tissues can help--the best areas are the neck, hands & wrists, and feet & ankles. It doesn't have to be ice--I've used a jar of pickles from the refrigerator in a pinch.
I'd be interested in trained opinions on the tepid (but not frigid) bath as a tool--is the water effectively pulling heat away from the body core as a heat sink, or does it actually promote hypothermia in the long term, with bad effects? (Yes, I know there are a lot of people out there who Aren't Into Baths, or who find the idea of sitting in the tub for long periods a sinful waste of time. This isn't about cleanliness, or about time management--it's about body temperature management.)
I'm working this week with East St. Tammany Parish Habitat for Humanity. Yesterday, which was particularly hot and sunny, one of our number appears to have suffered heat exhaustion after a long day manually grading a couple lots in Slidell: big pile of sand, shovels, wheelbarrow, and rakes (construction vehicles were unavailable). She spent last night in the hospital and her health is reported to be much improved.
Construction supervisors have been Very Very Good about nagging us about water and rest and sunscreen and shade, but nagging can only remind, not force; and the lady in question decided to go back to work on another site after we were done early with the grading. The supervisors had advised that we knock off early, given the level of sustained physical labor and the extra hot weather. She was the only one who didn't take their advice.
(The rest of us on that crew were OK, so far as I know. I saw most of them at this morning's roundup.)
I'm going to send the link to this article to the volunteer coordinators for future distribution. People need to be reminded that "drink water! pace yourself!" isn't just a nag to be ignored by the macho and willing; it's life-saving advice.
CBC story about hyponatremia (AKA over-hydration)
In it they mention that its what killed the woman who collapsed in the Boston Marathon in 2002.
They also mention that it's *much* less common than dehydration.
When I used to volunteer at Burning Man, one of the indicators of dehydration that we found very useful was irritability. If somebody's getting cranky, have them drink water.
My personal rule was that if the other people I was camping with were all ticking me off, I should go sit down for 10 minutes and drink a pint of water (or an Emergen-C, which has electrolites and puts one at less risk of water intoxication).
Nicole, in situations like yours, one thing I have found that helps get the hard-headed to take sensible precautions is the statement: "If you make yourself sick because you refused to use good sense, people will lose time taking care of you and less work will get done."
Volunteers are often less prudent about these things than people being paid for their work; in some cases, they have less experience with the bad results of overdoing*, and in others, they feel they have a mssion, and mustn't slack.
*Not just the personal results, but the effects of lost time on a project, accidents with severe injuries, and so on.
Very Young, I think of as toddler and below. Infants more so than toddlers.
The rehydration formulas we've talked about before are good: 40 cc of sugar, 5 cc of salt, in one liter of water.
Keep Gatoraide on hand. If it tastes good, you're dehydrated.
More on rehydration formulas here: http://www.rehydrate.org/solutions/homemade.htm
And keep your eye on your buddy. When he's showing signs of heat stress -- you're stressed too.
James, this is wonderful. I'm very tempted to print off a copy and have it on hand at Mythcon next weekend, where we'll have people coming in to oklahoma who don't normally see 100+ degree weather. Do you mind?
Fidelio, "having a mission" is the very thing that most endangers the volunteers here: the sense that you'd be shirking a needed duty if you slacked off. We all felt guilty about taking off early yesterday and kept explaining ourselves to each other. My guilty recitation was, "The next job they'd put me on is roofing, and we don't need me up on a roof all uncoordinated from being tired!"
I don't feel guilty about it anymore.
My fellow crew member seemed to be feeling fine when she headed off to the second work site. We all told her "take care of you," but that's really all the situation seemed to warrant at the time (yes, I know you're not telling me off for not having done more, no worries!). Her husband said that symptoms manifested over dinner. That rather indicates that it was already too late before symptoms began to show, and that's scary.
"Alcohol and sugar are very bad in hot weather"
The root beer float I had when it was 95 and humid here last week agrees with you. Fortunately there was a well-cooled public space with lots of drinking water nearby, because I could tell I was one step from official Disorientation, which for me is the feeling that I'm observing myself doing whatever I'm doing.
Be careful, all.
Tepid baths and showers are Good Things. Clearing out the pores to allow more effective sweating, warming and stimulating the skin a bit to promote vasodilation ... what's not to like?
Cold showers that shut down peripherial vasodilation ... not a good idea.
If you find you can't sleep due to the heat, might as well get up and take a tepid shower. You're not sleeping anyway, right? And you'll feel better afterward. Promise.
(Caffeine is another diuretic to avoid during very hot weather. But iced tea is ... well, it's swell. Iced green tea. Yumm! I could use some right now....)
Nicole, I've seen that a lot--and it's scary how fast we can go from "I feel fine" to "Um, not so much..."; individual tolerances vary so much, and so do individual reactions, which is why self-monitoring is key. Of course, if you haven't had much exposure to opportunities to overheat, it's really easy to miss the signs, or to think you've taken enough precautions, when you haven't. I've learned the hard way with heat exhaustion myself--and have had to snatch myself up by the scruff, figuratively speaking, a time or two.
Good on you for skipping the roof--it's a dangerous place to be when you're already hot. Here in Nashville, roofers in the summer prefer to be at work by 6AM, and to knock off in the early afternoon, for that very reason.
Good luck with the rest of the work!
As a (not so old) diabetic, I drank in every word. Believe me, a hypoglycaemic incident brought on by excessive heat (I've only had 4, and that is 4 too many) is not an experience I'd wish on anyone. Drink. Fans. Listening to what your body is telling you and not being afraid to say 'enough'.
We'd better learn to live with the heat, because it doesn't seem to be going away.
As always, Mr. Macdonald, thanks.
Many years ago I engaged in heavy-duty physical exercise in high temperatures for some hours and did not adequately hydrate myself. I ended up at the upper border of heat exhaustion. One thing that I found mighty confusing was that I felt cold, not hot. Nor did I feel at all thirsty, though other signs and symptoms of heat exhaustion were clearly present, i.e. nausea, weakness, headache, mild disorientation, cold clammy skin, and elevated body temp. As Jim and Sean said above: it doesn't matter if you feel thirsty or not, you must drink if you want to stay safe. Oh, and this can all happen indoors as well as outdoors. Large numbers of people exercising in an enclosed space when it's hot outside can overwhelm even a good air conditioning system.
Definitely avoid sodas. As a not-so-bright teen, I was in Japan on a high school band trip, during a major heat wave. Brightly, I drank only Coke for 3 days straight. No surprise I collapsed and had to be hauled off the hospital for some IV fluids and a stern lecture. In Japanese.
D
Heat cramps, heat exhaustion, heat stroke, aren't a progression. You can go directly from Feeling Fine to Heat Stroke without getting cramps or feeling thirsty enroute.
It’s a mammal thing. We regulate our internal temperature by internal means so we don’t have to crawl into cracks or sun ourselves on rocks.
Wait... nobody sent me that memo.
Can I crawl out of this crack now?
I was beset by heat stress while walking around Mt. Auburn Cemetery two weeks ago. I wasn't dressed ideally for the weather -- jeans, black T-shirt, and my hat was a dark blue Red Sox cap, not something sensible and wide-brimmed and light-colored like a Tilley hat. I started to notice tired, aching legs, at which point I told my companion it was time to get out and find some water; we were pretty far in, though, so I'd progressed to dizziness by the time we made it through the gates. I was strongly considering ignoring the rules and turning on one of the gardening taps just to splash my face (which my companion tells me was quite red).
Fortunately there was a supermarket very close by, and they not only had bottled water in the cold case, they had liters of Glaceau Smartwater with electrolytes. I was fairly sure that plain water would make me feel queasy, and so would sugary Gatorade, but Smartwater's not sweetened.
At Pennsic, when I used to go, we used to mix the Gatorade at half strength, on the principle of getting more water into people. The half-Gatorade-half-powdered-iced-tea blend my encampment liked was probably not an ideal hydration fluid, but it made it a lot easier to drink plain cold water after!
Where do red faces fall along the heat stress spectrum?
I've managed to teach a few of my friends here (Indiana, having a revoltingly humid summer) that continually wiping the sweat off your body is a Bad Idea -- it puts a temporary halt to evaporative cooling *and* dehydrates you faster. Learning that myself made a big difference in my ability to cope with the heat.
I find myself missing Texas summers. I grew up in Dallas, which on average is *far* less humid than Indiana, even when it's ten or twenty degrees hotter. Give me a hundred plus with low humidity over this eighty-three-and-hundred-percent crap we've been getting.
I'd be interested in trained opinions on the tepid (but not frigid) bath as a tool--is the water effectively pulling heat away from the body core as a heat sink, or does it actually promote hypothermia in the long term, with bad effects? (Yes, I know there are a lot of people out there who Aren't Into Baths, or who find the idea of sitting in the tub for long periods a sinful waste of time. This isn't about cleanliness, or about time management--it's about body temperature management.)
In general water draws heat away from the body 25 times faster than air. This can cause problems if water that is too cold is applied in high quantity. A shower is preferrable to a bath, because the temperature can be regulated faster. If you are feeling the heat, a shower that starts off tepid and v*e*r*y*s*l*o*w*l*y (like over a 15-30 minute period) moves to cold can be very refreshing, and can safely lower core temp. A mist defuser on a garden hose is usually safe to use at whatever temp your outdoor spigot water comes out at. As Jim noted, too much cold water can cause vasoconstriction, but mist (or standing in sprinkler) is generally ok.
Medics in the field would much rather use cold packs at neck, armpit and groin. Only occasionally do we resorted to extreme measures such as a cold water baths or packing in ice. Those are ALWAYS last resorts and should never be tried by anyone without extensive heat training, and specialized monitoring equipment.
Whoever was wondering about what very young might be: At my service we use 24 months as a guideline, but the treatments are still variations on the cold pack. We also include complete body wiping with damp cool washcloths for the wee ones.
And another thing -- animals get heat exhaustion, too. Dogs, especially, because they have very few built in ways to get rid of body heat, tend to overheat. Very playful, young dogs with clueless owners have been known to chase a ball in the heat until they (the dogs) collapse. I won't talk about other stuff stupid pet-owners do in hot weather, because it pisses me off too much.
Into which category does "feeling fine except maybe a little tired until I walked into an air-conditioned store at which point I really tried to faint" fall? This happened to me many years ago in a Dallas August, and I've always wondered just exactly what was going on. (I'd just walked about a mile and a half, which was not an unusual distance for me, even at those temperatures.)
Any skin color other than Normal is a not-good thing. As to whether red is better or worse than pale -- depends. Hot, dry, and red is worse than cold, clammy, and pale. Hot, dry, and pale is worse than cold, clammy, and red.
Red tends to go with vasodilation. Pale tends to go with vasoconstriction. The overall lesson, though, when it comes to body temperature, is that variations are bad. Get out of the stressful environment and see to your hydration.
From personal experience, you don't have to be doing anything physical to suffer heat exhaustion. I was in sixth grade in a Catholic school in LA, and we were attending services in the church on the last day of school. I started feeling woozy and was told by one of the nuns to go outside. I got as far as the sanctuary rail and passed out, bumping my head on the railing. I woke up in the nurse's office about five minutes later.
Don't forget pets. Friends of the family lost their dog to the recent heatwave in California.
The dog wasn't doing anything unusual that day, but the 110's instead of 80's-90's was too much.
It went from seeming normal to acting lethargic to starting to bleed- a sign of coagulation failure- in just 2 hours or so.
Into which category does "feeling fine except maybe a little tired until I walked into an air-conditioned store at which point I really tried to faint" fall?
I'm just guessing here, but -- I'd guess that the large vessels in your legs were pretty well dialated, you were getting a tad dehydrated, and when you stopped moving the blood pooled in the veins in your lower extremities, your blood pressure bottomed out, and until you started vasoconstricting again your body didn't have enough blood to keep your brain fully perfused.
Changing temperatures (from outdoors and exercising to indoors/air-conditioned) may have contributed to environmental stress.
If that ever happens again, lie down and put up your feet.
Oooooh, pets-in-the*-heat question:
Would having my shaggy dog's pelt shaved off help her cope with what may be a long hot summer?
I've heard two sides to this issue. One is that losing all that insulation helps them cool off. The other is that dog's don't radiate much heat through their skin anyway, and their pelts help insulate them from the heat.
Also: Does washing a dog's feet help them cool off? I know that their pads are one of their radiator spots. Just not sure if washing and wetting would help.
* "the" included so you wouldn't think I was talking about estrous.
one thing I've learned from camping at Burning Man is that good hydration is a habit, not a feeling. Hydration requires calculation, not thirst.
Because when it's pleasantly warm, but with bone-dry humidity, it doesn't feel like you're sweating.
One alternative-press newspaper there is 'Piss Clear,' named after the common advice in the desert survival guide. If one isn't drinking enough, there are signs. Yet even with the guide and the signs I've seen people have to go in for IV fluids because they didn't *feel* thirsty.
Red, hot, and filmed with sticky sweat, IIRC. In any case, the liter of Smartwater followed by a nice cool ice cream break at Herrell's and an hour's browse in Newbury Comics' air conditioning did the trick. I didn't pass out, and my legs stopped hurting.
I'm a baker. Fortunately, my current work space is in a nicely air-conditioned basement; I'd be willing to temper chocolate in my workspace, which I wouldn't dare try under less friendly conditions. Two summers ago, I was working in an un-air-conditioned kitchen, within arm's reach of two deck ovens which ran pretty constantly at 375 F, and I went through pitchers and pitchers of iced tea, over enough ice to dilute it further, very lightly sweetened from my stash of lemon sugar -- what I do with lemons that I'm juicing and don't immediately need the zest; a few minutes with the Microplane into a bucket of white sugar makes something that's very useful to have around.
The diuretic properties of the iced tea were probably not the best for me, but it went down SO much easier than plain water.
Into which category does "feeling fine except maybe a little tired until I walked into an air-conditioned store at which point I really tried to faint" fall?
If cooling off makes you feel sick, it means you were starting into the heat stress (exhaustion) zone. It happened to me, despite a gallon of water and Gatorade a couple weekends ago after 10 hours at an outdoor event. I felt no symptoms until getting into my air conditioned car, and then the nausea hit... The immediate treatment is to cool down more slowly... turning down the a/c to a low level brought immediate relief from the nausea.
One note to all: Once you have gone into any heat stressed state, you are MUCH more vulnerable to a repeat episode for the rest of that, and even the next, day... If it hits you and you rehydrate, DON'T go back out into the same activities again that day. Go home, stay cool, drink water/gatorade, get a good nights sleep...
It's also quite important for people who're taking medications to realize that they are at a much higher risk, in or above the category of young children and eldery adults. This is especially true for people taking anything that already dehydrates you or gives you a cotton mouth - since you're accustomed to feeling that dry mouth, you are at much greater risk to wave off the signs of heat stress.
"Oh, my medications always make me dizzy..."
"I always have a dry mouth/funny taste, it's no big deal..."
Many medications also thin the skin, making you much more susceptible to sun burn and the effects of the heat. Folks taking chronic medications should be especially vigilant in consuming enough water, and staying in shaded, cool places until the temperature returns to something closer to normal. They should also take it easy with the heavy labour, as again, their body ability to regulate itself is off kilter due to the medicine.
Take it from the girl who's been trying to pack, and spent all of yesterday on the couch remarking on how dumb she can be...
"Shopping malls, office buildings, movie theaters, are all air conditioned. "
Oh, I wish. However, I live in the UK, where it's not always the case for the above places. By the way, I'm a teacher, and I'm on my first week of the summer holidays. (We ended the term on 21 July; we return on 4 September.) I really did think that my school was somewhere in one of Dante's circles of Hell this month (we're in a heat wave over here also!); I just couldn't decide which one!
That said, I appreciate this article! :)
Almost 20 years ago, when I was in the Air Force, working on the flight line, I came down with a bit of a stomach flu. One day of hell on earth (why is my body trying to turn it self inside out, from both ends?), another day of rest and then I went back to work. Being sick was over the weekend so no one at work knew anything about it and I was out on a hot flight line in July, wearing dark green long sleeve shirt and pants. I don't remember feeling any warning signs; just that I woke up in the hospital with an IV in each arm and shivering uncontrollably.
If you've been recently ill, you have a greater chance of having a heat/temperature related incident.
Thanks for mentioning that it's not necessarily a progression. I had been working outside this week trying to remove a tree trunk and managed to give myself a pretty bad case of heat exhaustion. But I didn't remember feeling any cramps, just getting to a point where my heart was racing and my stomach felt upset.
Keep Gatoraide [sic] on hand. If it tastes good, you're dehydrated.
This is the single best rubric for dehydration I have yet found. Even better, if someone takes a sip of one of the Truly Vile flavors, makes a face, and then chugs the vessel to empty, they were really VERY dehydrated.
Your body knows what it wants. Giving it what it wants is a good way to keep healthy in the short-term.
Read, absorbed, drank a glass of water, took one to my husband, came back and linked this. Thank you.
Keep Gatorade on hand. If it tastes good, you're dehydrated.
Watch out for the Fun! New! Flavours! You know, the ones that are designed to ALWAYS taste good.
It's not easy to drink enough Gatorade, but it is certainly POSSIBLE.
There's a stereotype about Californians with bottled water, that it's because tap water isn't good enough (or something dimilar). Most of those bottles are probably filled with tap water. If you have to travel for any distance in hot weather, that bottle comes in handy. If you start feeling warm suddenly, even in an air-conditioned environment, the water bottle is your friend. Drink some; you'll feel better after.
That said, after being out and about for a couple of hours this morning - it's not that hot, only about 90F, but humid! - I had lemonade with lunch. Electrolytes, of a sort. I've also bought mineral water, and had it help. (Like Gatorade, if it tastes good, you needed it.)
Some tap water in California isn't good enough. I don't have much problem with San Francisco, but San Jose is mildly icky.
Whatever's coming out of the tap in Anaheim isn't water. On our list of things to do upon arrival at Worldcon is buy a case of bottled water.
Just one word about bottled water: refill 'em bottles. The tap water in many, many places (like London) is quite good, is quite pure, and drinking it doesn't involve producing a plastic bottle, powering a bottling plant, moving the wee little plastic things across continents, selling them vastly overpriced, and then producing millions of non-degradable, difficult to dispose of plastic empties.
I buy the odd bottled water now and then, because I need it, but I always resent it a lot.
Kelly has a good point about some medications making people more vulnerable to heat stress. A person can start taking the medication in winter and think he or she knows the relevent side effects, not even reading the pharmacy warnings when refilling the prescription, but it really is different in summer.
If anyone is using transdermal patches for continuous release of medication, remember that some of them are sensitive to temperature. When skin temperature increases, the active ingredient diffuses out of the patch faster. (A person could overdose that way. In theory, at least.) Some kinds of patch also have problems with adhesive not working after it is exposed to temperature extremes. You have to store the patch at 55-75 degrees F before use...which means a person without access to continuous air conditioning cannot use the medication. Bandage tape is great for helping the patch adhesive stick better, but if the patch can't stick at all by itself, the active ingredient won't transfer and you're wasting your time and tape.
I've had heat exhaustion twice this month because I've had to be out in the heat for tests prior to the PET scan (which I had yesterday and came home with something very close to more heat exhaustion). Usually I stay home when it's this hot. I've been in today, and only have to go out briefly tomorrow.
And here I thought the "if Gatorade tastes good, you actually need it" was my own private thing. At the Boston Marathon, course First Aid stations stock quarter strength Gatorade -- full strength is way too strong if you're dehydrated.
ISTR that you can sweat out fluids faster than you can effectively rehydrate orally, so if you get behind in hydration you can be in big trouble.
Hyponatremia is rare, but has been a continuing topic of the Marathon First Aid briefings for the years that I've been volunteering. And I think that I actually saw a case once - she had been running at mile 14, and was on the ground seizing a few hundred feet farther on. She was still seizing when the ambulance finally got to her several minutes later.
Consumer Reports has compared bottled water with tap water, and frequently big-city tap water comes out on top -- I think that New York, Boston, and LA have all been near the top (with a caveat about "last mile" infrastructure making all the difference). The worst water I ever tasted was in a small town in Wyoming. There are some good tasting mineral-waters, but sulfer-water isn't on the list.
Oh, joy. I read this right after taking my evening dose of a beta blocker. Well, hypertension's not good for you either, even if it's slower than hyperthermia.
My a/c also gave up the ghost last summer. Fortunately I can open up windows on three sides of the house, and the big box fan gets moved around to where it gets me the most effective ventilation. My house also sits into the side of a hill; downstairs is street level at the front and effectively a basement at the rear. It's not useful living space, but I can hang the box fan in the top of the stairwell and pull up somewhat cooler air.
Until a couple of days ago, I was working a temp job collecting petition signatures. Tuesday I was out on a shopping center parking lot, trying to stay in a little patch of shade when not actually talking to people. When the first leg cramp hit I didn't think much of it. When the other leg started cramping too, I realized what was up. Off to a close-by fast food joint for a small order of fries, well salted, a bottle of water, and some sit-down time in air conditioning. Went back to work after about 15 minutes, but was ready to break for the closest cool spot if any further trouble ensued.
Once again, Mr. Jim, you da man.
On top of all the wonderful advice I would add one more technological wonder that has saved me.
A couple of years back I was complaining bitterly about the New York summer and the hell that is the New York city subway system to my fella.
Two days later a package arrived in my office, containing a Sharper Image cooling unit.
At least for me, this bloody thing works. It is essentially a mini AC unit. You fill the side chambers with water, put it around your neck, and turn on the fan unit. It sends cool air to your jugular...and your body temperature goes down, cooling your blood. I actually feel cooler than the air around me.
The thing originally sold for $100. The latest Sharper Image catalog has it down to $29.
Nope, no global warming. Nothing to see here...and no corporations understanding that they have a product that they can sell to the masses because there is No Global Warming...
--claire
Great post. Thank you.
I'll second the comments about paying attention if you're on medications and particularly mention antibiotics, many of which already come with a warning to avoid too much sun.
Also, thank you for the mention of Water Intoxication. A good friend of mine died of hyponatremia last summer while training to be a DC bike cop. He was so concerned about keeping hydrated and not getting heat exhaustion that he went too far in the other direction.
Claire's comment reminded me of the useful cooling neck wrap / bandana. The bandana is filled with a polymer which, once soaked, keeps your neck cooled by evaporation. Works well in the desert.
The one I have was handmade- here's instructions on how to make them [2 lbs of polymer for $18 including shipping, makes 100 bandanas at 2 tsp per. Note, this is merely the first search hit and not an endorsement]:
http://www.watersorb.com/polymer_cool_neck_bands.htm
and I'm seeing them for sale as the 'Cobber neck wrap,' or the 'Thermo-cool,' etc. I'll assume many sporting goods stores carry them.
'nother suggestion to keep one hydrated - vary the flavors of the water.
I find that if I have bottles of _just_plain_water in front of me, I'm likely to shirk them. But if I doctor said bottles (mostly Nalgenes of varios eras) with _something_ to make it taste less, well, watery, I'm more likely to keep hydrated. A blump of lemon-juice concentrate, a blob of cranberry-juice concentrate per liter of water will make the water easier to drink. There are also some Mexican/Central American concentrates (tamarindo?) that perform the same function.
I've also been taught to dilute Gatorade (tm) half and half with water for better electrolyte balance.
pr
OTOH, talk about switchel? proto-gatorade, I tell you...
Another home-made drink, probably similar to switchel, is the middle-eastern sekanjabin:
2 cups water
6 cups sugar
1 1/4 cups vinegar
a couple of stalks of mint
Boil the sugar and water together until the sugar has dissolved. Add the vinegar and simmer 15 to 20 minutes more. Remove from heat, add mint, and let cool.
Use 3 or 4 tablespoons in a glass with ice and water. (Also this syrup can be used on romaine for a snack or salad.)
(Recipe from Maideh Mazda, In a Persian Kitchen)
If you lived, as I did, in California's Contra Costa County where the tap water was essentially drawn from the Sacramento River Delta, bottled drinking water was essential. In summer, reduced river flow meant saltwater intrusion from San Francisco Bay, giving the water an awful taste. In fact, the local paper used to publish the daily sodium level along with the usual weather statistics.
LA's tap water doesn't necessarily taste bad - it depends to some extent on where you are, because the sources vary from area to area - but like most of the water in the western US, it's hard. (I've heard water described as so hard you need a cold chisel to get it out of the faucet. This isn't quite that bad, but I won't put it in my electric tea kettle without running it through a filter.)
I do, however, refill my bottled-water bottles from the tap. I suspect a lot of the bottles out there are refilled the same way. Why waste a perfectly good bottle?
With regard to washing a dog's feet to cool the dog off -- I don't know. Ask a vet. A dog of mine got hyperthermia once: I carried him inside, dumped him into the bathtub, and ran cool -- not cold -- water over him, making sure his head was out of it. He revived completely and was fine. He was a young, strong dog. This weekend my three year old dog (a different dog) was clearly in some distress (lots of panting) from the heat. I did the same thing, essentially -- got him wet with cool water from a hose -- and then took him into the shadiest spot in the back yard to rest. It seemed to work; he was fine in a little while. Both dogs had thick coats, which probably exacerbated their condition; I would think that a thin-coated dog would be less susceptible to heat, though more susceptible to say, sunburn. (Yes, dogs can get sunburned.) But again, I'm not a vet.
I will here put in a plug for the geothermal heat pump, a slightly higher-tech version of the cool basement and one of the most energy-efficient cooling and dehumidification technologies. I think we're going to be hearing a lot more of it in the future, in places with hot humid summers.
I wish I had seen this a few days ago, when we were in the god-awful heat wave. And air conditioning would be nice...in the absence of such, using cold clothes draped in front of the fans helps slightly. Here in Northern California, we're not supposed to *need* air conditioning, heh.
I ended up with heat exhaustion on Election Day in 2004. I was working as a election monitor in Tampa, Florida, and was wearing a black dress (the organizers said "business casual," that was the only thing I had with me that worked), driving around in my mom's unairconditioned car. It was 90 degrees, with close to 90 per cent humidity, and I was spending most of my time outside. I was fine for a while, and then I realized I was getting weak and disoriented. I ended up having to sit in the Mexican restaurant that was the staging area for the monitors for a couple of hours and drink large amounts of lemonade.
I wish that that were the worst thing that had happened on Election Day.
Great article. Couple of points: as far as I remember, the pulse is another way to distinguish heat exhaustion from heat stroke. Heat exhaustion produces a weak, rapid pulse, as in shock; heat stroke produces what our instructors call "a fast, bounding pulse", ie rapid and vigorous.
And "change in behaviour" can be very dramatic. Aggression is common. The example given is:
"Are you OK?"
"I'm £$%!ing fine. £$%!ing leave me alone." (punches enquirer)
"Right, you have a heat injury. You two, grab him."
One effective and low-tech trick for room cooling - especially in the absence of air conditioning, which we hardly ever get at home here in London - is to put a large bowl of cold water in front of your fan. It's not big enough for a proper lake effect, but the difference in the specific heat capacities of water and air means that the water can be sitting there for a day or so (I change it after that, due to dust rather than temperature issues) and still absorb heat from the fan blast going over it. I notice a big difference doing that rather than just sitting under the fan.
People have mentioned "pee clear", but what nobody has mentioned is that you do need to be peeing. If you aren't having to go to the bathroom at all over say a 4-6 hour period, you aren't hydrated enough for the hot weather.
I've learned over the years that even under normal circumstances I have to be sensitive to my hydration state. Fortunately, my early-warning signal is a headache. If I get one, even a slight one, I go get water immediately.
Ah, something I can comment about (having lived in Australia all my life). First thing to note is that if you're in a humid climate, sweating isn't going to help you cool down, as the moisture on your skin isn't going to evaporate. However, if you live in a hot, dry climate, air conditioning may not be necessary (and may actually dry you out further). Instead, get yourself a standard fan, a plant mister, and an open window. Switch on the fan, mist yourself with the mister, and sit in front of the window.
Oh, and my personal warning sign for when I'm drying out: my eyes start to get dry. This tends to happen to me if I've spent far too long in air conditioning which isn't sufficiently humid without keeping the water levels up. I've had this happen more often to me in the middle of a cold, dry winter, because I don't tend to drink enough water under such circumstances, especially when I'm working in a nice warm airconditioned office.
On the subject of pets, when the mercury starts rising, I put a few ice cubes in the kitties' water dishes. We used to do this for our dogs when I was a kid, especially if they had to be outdoors in a Louisiana summer.
I'm not sure how the cats heat-regulate. It seems to involve a lot of lounging around on the basement floor and nagging me for ice cubes.
I stay away from Gatorade and other vile-tasting good-for-you drinks -- my subconsciousness is quite effective in making me forget that I need to drink if the only thing available tastes bad, even if I'm already cross-eyed from a dehydration headache. 1/5 fruit juice and 4/5 mineral water usually works fine for me. (But then, I'm a wuss about heat, I shut down when everyone else is still enjoying a "nice warm day".)
When I think of the old wives' tales about drinking in hot weather (or at all) I wonder how many people they got killed. Things like, "Do not drink when it's hot, you'll sweat", or "do not drink before going into town, you'll need to use a public bathroom and they're icky", "do not drink with lunch, it's low class", "do not drink on an upset stomach"...
The Cool Ties look great. I've always used the old trick of soaking a bandana in water (dripping, not damp) and tying it on my head. Everyone thought I was mad until they tried it.
inge,
"do not drink with lunch, it's low class",
???
What could the reasoning possibly be here? Could you tell me more about your cultural context where you learned this?
Re: electrolytes
I have it on good authority that most people* tend to do okay with having enough sodium on hand (we like our salt in North America), running out of potassium is also a huge problem in the heat. The symptoms are more noticeable, however - you pass out and fall down instead of getting cramps, etc. This is handy, since the symptom is:
a. hard to miss
b. likely to lead to medical intervention
The technical explanation is that elecrolytes (dissolved sodium, potassium, calcium, chloride, magnesium, etc) are to your nervous system what electrons are to a computer. And that running your brain without the equivalent of electrons = teh reboot.
I am also informed that a single banana has more than the RDA of potassium, and unless you are a heavy exerciser (= bicycling enthusiast) one in the morning will do you just fine.
Disclaimer: I am not a doctor, this is not medical advice.
-r.
*in the United States, for some values of most people
Excellent article, and very good points.
I work in an aluminium smelter where the air temperature can get well above 60 deg C on a hot summer's day. The rule there is that you and nobody else knows how much heat you can take. Keep hydrated.
One sign of heat exhaustion I've experienced myself is that you may feel you're freezing and actually start to shiver. This is a pretty obvious sign that your body has had enough and the thermostat isn't working anymore. Walk away to somewhere cooler, because nobody wants to have to carry you.
With practise, you know how much you can take, and how much you should take.
Go to within 90% of your limit, and you need a half-hour break to be back to full capacity again.
Go to within 95% of your limit, and you need an hour, maybe two, to be back to full capacity.
Go to a 100%, and you'll just drag yourself out and feel useless the rest of the day.
As someone who's going to Pennsic in a western PA summer in about a week, let me thank you for this advice. The parts about what to look for I knew, having had heat exhaustion once...and once was enough; now I know what it feels like.
I have this urge to print it out and give copies (properly attributed) to everyone I see at War. :)
Low electrolytes is also a good excuse for eating fries. (Potatoes have potassium.)
One of the more noticeable signs of low potassium levels is muscle cramps. (Been there, done that, eat lots of bananas as a result.)
Oh yeah, and there's fog this morning in LA. For a while, we'll have normal weather.
My trick for sleeping without AC in the hot'n'humid weather is to get my nightshirt soaking wet and point two fans at my body. By morning the shirt is dry and I've had a good night's sleep.
Is there any physical reason this isn't a good idea?
"do not drink with lunch, it's low class",
???
What could the reasoning possibly be here? Could you tell me more about your cultural context where you learned this?
Who needs reasoning? It's a class marker, like which way you turn your fork when you eat peas, or whether you say "pardon?" or "what?", and class markers are self-supporting without external logic.
I wish I had seen this a few days ago, when we were in the god-awful heat wave. And air conditioning would be nice...in the absence of such, using cold clothes draped in front of the fans helps slightly. Here in Northern California, we're not supposed to *need* air conditioning, heh.
Y'all are further south than the NE ;). The Pacific Ocean is a good heat regulator, but it's not perfect.
re: electrolytes
I'm really prone to drinking enough water that my electrolyte balance is starting to go the wrong way. If I go with the "pee clear" advice, I'm not getting enough salts (this probably has a lot to do with a hypertensive, diabetic mother and eating minimally processed food... I don't salt my own cooking enough most of the time). I'm best off if I alternate water with tea, lemonade, orange juice or other drinks with Stuff in them. If you're having to pee every hour or more, and the water tastes *really* good... drink something with salts in it. ASAP. Or eat something really salty. Pickles are good. Citrus juices have lots of potassium, which is a happy thing. Jerked meat is good stuff too.
The other trick I like is wear a hat and stick a bag of ice on your head. Note that you do this *before* you go out in the heat, not once you've started to have trouble. Get your bag of ice and hat and sunglasses and put them on before you go out the door.
If it's hot enough that I want a bag of ice for under my hat, I've got a quart container of liquid that goes with me. Everywhere. A half hour or so generally means it's nearing empty. Even if I'm not feeling thirsty when it's empty, it's time to refill. By the time I do want a drink again, I may not be anywhere near a spot to get liquid. Anything less than a quart is too small if I have to be active... a quart generally will last long enough for me to get to a place where I can refill. Try to vary the refills, you're pumping a lot of liquid into your body and you probably aren't eating much as a result.
Lessee. Other thing is if you've got long hair, get it sopping wet before you go out in the heat. Even in very humid areas, that will help keep you a little cooler. Means your body has to heat up all that water. If it's dry air, it works even better. This also lets you monitor the humidity easily, so you can judge how that will affect your heat management.
If you can't get into a tepid shower, run tepid water over your hands and wrists at a sink. Your hands are one of the big radiation surfaces (head and feet are the others), so bringing the temperature down there helps. Washing your feet can be good too.
(no, I've never had more than a red face from heat, and I don't intend to start now.)
Ajay, good point. Extreme heat makes you think funny. Yet another good reason to keep hydrated and pay attention immediately to early signs of hyperthermia: once it affects you, you may do stupid stuff like thinking that you're fine, and refusing water because you don't feel thirsty.
Great article! Hits home with me.
I work at the Southern California Rennisance faire.
My job? Watergirl.
With the heat climbing into the 105 range at least once a run, we have a lot of problem with heat exaustion. We call it 'going down'(not intended to be crass.)
The issue with us is that we're all in costume. 16th century, heavy, made-for-a-cold-climate costume. In the So. Cal sun, this can be very bad.
Things to keep in mind if you cannot get out of the sun/must wear horrible clothing:
Do NOT wear synthetic clothing if you can help it. I mean it; a cotton/poly blend will put somebody down way faster than a 100% cotton or a linen.
If you're like us and have to wear wool, WEAR it. It is acutaly cooler to be completly covered in a layer of linen and a layer of wool than just the linen. The reason? The sun can't get in. If the sun doesn't penitrate the clothing, then the hottest you can get IN the clothing is 98.6, right? Think of desert wanderers, and their head to toe outfits. It's like your own personal tent.
This is one of the reasons those of us in wool can run around at the fair while the people in the light gauzy things fall down.
Of course, the fact that we are drinking about a gallon of water apiece every hour or so helps. And we have platters of pickels, oranges, watermelon, olives and pretzels out.
Dispite all of our precautions, we occasionally go down. Last time *I* did it (and it was embarassing, as I'm a frekin water girl) I fell asleep in the shade and the damn planet rotated, putting me in the sun. I had taken off my wool overdress, and the sun got right in there. Stupid me. Now, if I sleep, I cover myself with a nice wool blanket. Take that, Mr. Sun!
The other nice thing about wool is that once it gets soaked with sweat it gets its own evaporative cooling going and can dump a lot of heat.
Natural fibers are definitely the way to go.
I fell asleep in the shade and the damn planet rotated
The beastly thing! How dare it. I hate when that happens. Give me the dark side of a tidally-locked world anytime.
I never knew that about wool. That's interesting and useful.
Bananas are a good source of potassium, but they have two drawbacks: eating them can cause serious bloodloss in a mosquito-bearing environment, and they have too much sugar and starch.
Which is my problem. I just can't have as much sugar as comes with all this stuff, the cool Appalachian recipes, the Gatorade™, the bananas and so on. Or as much starch as is contained in peanuts or pretzels. I eat salted almonds, which are OK, but what can I do about potassium? When I'm home I eat pickles, but they're not too convenient to carry on a hike, or even around the city.
This is important to me right now, because I'm going to be taking two elderly folks (my parental units) around NYC doing touristy things in a week and a half. I'll carry water and the aforementioned salted almonds, but...
I wish I'd thought of the cool shower trick two weeks ago. (Southern California, no air conditioning.)
The Army was kind enogh to give me a mild case of hypernitremia, at Basic Training. We were, because of the heat, being made to drink one qt of water per hour, from about 0800, to 1800. After some days of this, I was the victim of the effects.
The worst part of it was the feedback cycle. I felt as though I were starting to enter heat exaustion.
What I've since read/been told, is that much more than about 6 liter of water is more than the system can handle, and that, should one be losing so much water that intake at those levels is warranted, one must up the intake of sodium.
Sidenote, story of grim nature: I got medevacced to Germany when I did (I being a "routine" evac, resulting in my being dependant on an open seat; no rush, and all) because a kid at the base I was stationed on (180 miles SSW of the hospital I was in) dropped in the mid-day sun. It was Heatstroke, which is a priority evac.
There being room on the plane, I was told to grab my kit. It was about forty minutes from getting the word, to being in the air.
As expected, he didn't make it.
TK
Dear Mister James McDonald,
thank you very much for your advice in not-dying. I, personally, am a not-dying enthusiast and have been practising it for nearly twenty-six years now. I am hoping for a long and successful career in the field of not-dying, and I am very grateful for every bit of advice.
Long live the internetational (it's kind of like international, but it happens on the... oh, I see, you got it already... I'll be moving on) not-dying movement!
(no but seriously--very good article. If I may exhibit hubris by commenting on the STYLE of your article, as if I were in any position to comment on your style: the mixture of well-researched termini technici (or terminus technicuses? ;P) and very plain and sometimes even funny passages makes this an entertaining read, keeping the reader awake (it's hard to laugh while sleeping) (though I bet not impossible) without downplaying the seriousness of the topic. End of hubris.)
Mouse: I work that same faire (and have for decades, but I digress). Inside the clothes can get above body temp, the moreso if those clothes are tight-fitted.
One of the things (more common in Agoura, where the temps were much higher, on average) which always amused (for certain values of amused) was that when the temperature went down, to them upper 80s/lower 90s, the customers were fine, the partipants started to go down.
They felt cool, and stopped drinking.
TK
Xoper, combine the salted nuts with roasted shelled seeds like pumpkin and sunflower and sesseme. Or find those square german iron ration sassages forgotten the name but like really chewy pepperoni that is safe without refridgeration or a good jerky.
You could just put some pickels in a zip baggie.
Xopher: Potatoes (though they have starch).
OJ has more potassium than bannanas. It has sugar, but not so much starch. Grapefruit is also (I think) fairly rich in potasium.
Worst case, use the salt substitutes, once in a while, in the cooking of some needful food.
TK
A belated thanks, Jim & Edward... Toddler/Infant is what I would have guessed, but I wanted to hear (see?) it from Some Sort Of Authority.
- I found that even in a moderate climate - even when it's freezing cold - making myself drink has noticable effects on my stamina and ability to concentrate. Get into the habit of always having a drink at hand and sipping frequently. Carry water in your car as a matter of course.
- airconditioning to cool down is great, but I find it much harder to cope with temperature differences between moderate heat (up to 35C) and aircon (sometimes set at 25C) than to employ ventilation and extra water, inside and out. Aircon has other disadvantages: many people who could adjust keep in their comfort zone and never try to adopt to outside temperatures, which means, of course, that they are uncomfortable as hell when they do have to go outside, sit in hot cars, and cross large parking lots. Aircon uses up a lot of energy, and a side-effect of lots of people using aircon in cities is that the cities - which are already warmer than surrounding countryside, thanks to lots of stone emanating heat - get even warmer. London just has the second day of aircon-induced localised blackouts...
The city of Freiburg, Germany, in its pedestrianised centre, has a system of very shallow canals (7km) through which water from a local river runs.
I realise that this - like the recommendation only to use air conditioning when and where it's really necessary - is not practical for all climates, but the temperature inside the city centre is on average two or three degrees below that of the next measuring station a quarter of a mile away.
Xopher -- being a low-carber myself I sympathize -- bananas and dried apricots, great sources of potassium, are bit high-carb for anything but a treat or an emergency for me. I take a potassium vitamin, but I don't trust it. Spinach, other dark leafy greens, zucchini, watermelon, strawberries, broccoli, and mushrooms are lower-carb potassium sources but a bit harder to tuck in your pocket. I wonder if home-dried strawberries, either cut up or pureed to make fruit leather, done with no added sugar or maybe some Splenda, would a) taste okay b)retain enough potassium? Must experiment sometime...Or if you could find apricots dried with no added suger, they are fairly low-carb when fresh. But for just salt, you probably can't beat jerky, and meat does have some potassium. (oh, unless you're vegetarian -- you may have said but I don't remember.)
PJ-
Tasty variations on the recipe for sekanjabin include: rose, cinnamon, lemon/orange/citrus (handful of candied peel), and rasberry. While they don't have the cooling effects of mint, they're still quite good and give some variety to my gallon containers of syrups. I've got chocolate mint getting happy in my fridge for Pennsic right now, and the rasberry will get made this evening after the temp drops somewhere below 80...
I can't vouch for the usefulness of this product, but I've been thinking of getting a couple sets of shirts/pants and keeping them handy.
They're for blocking sunlight for people with sensitive skin, but if you were going to be outside where it was hot, I would think this might qualify as portable shade.
I can't figure out what material they're made of. But I'd assume cotton.
Vegetarian (no sausages), low-carb (no potatoes, no OJ), prone to kidney stones (no spinach), take a statin (no grapefruit).
Pumpkin seeds it is! (I'm allergic to sunflower seeds, and sesame seeds are kind of tiny.)
Thanks everyone!
Greg, I have the "safari jacket" from there. It's not particularly cool, despite being vented in the back (well, to be fair, the huge backpack I generally carry makes that moot), but it does keep the sun off nicely.
I got their least dorky-looking hat, and it was too dorky-looking for me (me!) to wear. But I do wear the jacket.
I have OJ with my breakfast each morning - calcium-fortified to boot. Eat bananas, spinach, and broccoli frequently (not together - no, I don't want a recipe for a combination). I'm probably OK for potassium. What I mostly did for the past few weeks, having to be out in the heat, was: a. Stay in shade whenever possible
b. Drink lots of water
c. Wear a hat
d. Have some kind of salty snack every now and then.
Most days we started out in late morning and stopped at some fast food place for lunch before really getting to work. Fast food will give you more salt than you need without putting any extra on the fries. The day I had the leg cramps, we hadn't stopped for lunch.
I figure, even being under treatment for hypertension, while I should watch my salt intake, I still need more in hot weather.
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The Island with Ewan McGregor and Scarlett Johansson
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Gurer V jnf, jngpuvat Gur Vfynaq. Naq urer pbzr bhe ureb naq urebvar, rfpncvat sebz gurve negvsvpvny raivebazrag, nf vaabprag nf Nqnz naq Rir ba gurve svefg qnl va Cnenqvfr ... vagb gur Nevmban qrfreg. Naq zl vafgnag gubhtug jnf, "Gurl'er qrnq."
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If broccoli is high in potassium, I'm fine. I eat broccoli all the time. I like it raw, or slightly steamed, so a Ziploc™ of florets will do me fine.
Anne, do you know if your hypertension is salt-sensitive? An endocrinologist I once knew told me that only one in seven hypertensives has the salt-sensitive kind, though the percentage is higher among African-Americans. (She's the same one who told me that MSG turns into GABA in the brain.)
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