Monday, May 7, 2018

First Aid: Environmental Emergencies


 
T2
Hour 3

Bonus Review: Snakebite Kits

References:
Warrior Skills Level 1 , pp. 3-35 through 3-27, 3-83 through 3-88
First Aid, pp. 5-1 through 5-19, 6-1 through 6-14
New Reference download:
FM 21-10 Field Hygiene and Sanitation June 2000 , entire manual!

Highlights:

Individuals cope best with environments out of their ordinary climate best with proper diet, sleep and rest , exercise/fitness, and appropriate clothing for the environment. (Maybe you can guess why we keep hitting certain buttons?)

Acclimation is the best preparation. This can take 5 days to 2 weeks, or more.

Water requirements in hot , dry climates may increase to over 1 quart per hour with arduous activity. Pre-hydration prior to physical activity is preferable, but do not exceed 1¼ quarts of water consumption per hour! Over-consuming water can lead to hyponatremia, from over-dilution or actually flushing too much sodium out of your body, a potentially life-threatening condition.

Urine = hydration status. If you aren't peeing, you aren't drinking enough. And by the time you feel thirsty, you're already 2 quarts or more behind on your body's needs. Increased respiration and sweating, esp. when sweat evaporates rapidly in hot, dry climates, increases your body's water loss before you notice it, and you may not feel thirsty even as you dry out. But if you're drinking enough you'll pee, and it should be clear to pale yellow, and normal quantities. If you're just putting out a little, or it's darker, you're not drinking enough.
Easy peasey rule = clear and copious urine.

Sunscreen and lip balm with an SPF of 15 or greater is indicated for exposed skin in both hot climates and cold, because of increased UV exposure in both.
Easy Rule Of Thumb: 100 divided by SPF = percent of UV getting to your skin.
E.g.=
SPF 4 means 25% of the sun and UV is hitting your skin versus wearing no sunscreen.
SPF 15 means you're getting 7% of the sun and UV you'd get with nothing.
SPF 50 drops that exposure to 2%.
Once you hit SPF 15, the cost/benefit may be a diminishing return, but in the tropics, or at altitude, you may need SPF 50 or more, due to increased UV exposure.
Reapply frequently.

In cold temperatures, layers are vastly better than one heavy covering.

If your feet are cold, put on your cap.

Urine is still predictive: you can dehydrate in cold climates as well as hot ones.

Change wet clothing and socks as soon as practical.

If immobile, move feet and hands. if possible, work large muscles; this is how your body produces heat.

Sunglasses/goggles are essential in snowy climates. The UV can cause snow blindness to unprotected eyes that takes days to heal. During which time you've literally sunburned the inside of your eyes, you can't see to do anything, and it's extremely painful the entire time. After you've done it is too late to realize you should have protected your eyes.

Alcohol and caffeine are both diuretics, and will dehydrate you faster. Avoid them in temperature extremes. If you just have to have your morning joe, you need to compensate by increasing water intake as well.

Use DEET (mil-spec is 75% strength, FYI) on exposed skin, and permethrin on clothing, to repel biting insects and the diseases they carry.

Don't play with snakes or other wildlife, and your risk of being bitten or stung drops tremendously.

Turn out boots before putting them on, and watch where you stick your hands and feet in areas where snakes and other problem species reside, especially when stepping over logs, rocks, or reaching hands up onto ledges.

Do not cut snake bite punctures.
Do not attempt to suck poison out with your mouth.
Do not put ice on snakebites.

Bee/wasp venom is a protein; the best thing to put on that is an enzyme that breaks protein down. Commercial sting relief products may help. So will Adolph's Meat tenderizer, which has the active ingredient papayin. The same thing that makes meat tender by breaking down the protein inactivates many insect stings the same way.

Stingrays live in cold waters (colder than your body, anyways). The fastest way to inactivate the sting of a stingray is to immerse the extremity stung (usually a foot/lower leg) into a bucket with the hottest water you can stand soaking it in. Think jacuzzi hot, not boiling, please. In a matter of minutes, the venom will self-destruct from this treatment. Remove any detectable stinger/foreign body, and then treat it afterwards like any other open wound, i.e. clean, disinfect, dress and bandage it. Zombie Steve Irwin reminds you not to play with stingrays when your chest is in proximity to the tail, unless you're also wearing your kevlar vest and SAPI plates. Crikey!

Specifics:
Heat injuries come in three types, from least serious to most serious:
* Heat cramps.
* Heat exhaustion
* Heat stroke
Heat cramps are painful. Hydrate, and increase electrolyte intake, via sports drinks or saltier food. Do not take salt tablets, which merely increase your body's need for water, to dilute them in circulation.

Heat exhaustion victims are cool, pale, and sweaty.
Their core body temp is between 101° and 103° F. (You'll only know this with a rectal thermometer.
Move them to the shade, a cooler place (if such is possible), let them rest, remove burden/packs, loosen clothes, and cool them down with water applied to the body.
Fluid replacement and work/rest guidelines. This embiggens.
Heat stroke victims are red, hot, and dry. Probably dry because they've run out of sweat to try and cool the body down.
Their body core temp will be 104° F. or higher.
They are in a life-threatening condition, and their brains will cook and turn to tapioca rapidly beyond 106° F., and they'll start having seizures, if you don't take immediate action. For example, at Quantico during Marine OCS and Basic School, where it's black flag (greater than 90° and greater than 95% relative humidity) pretty much an hour before the sun comes up in the summer time, this would include taking officer candidates and/or shiny new second lieutenants, stripping them of all gear and clothing to their skivvies, and dropping them in a kid's wading pool full of ice and water, with a mean pool temp of 40° F.
As Navy corpsmen dump more ice into the water every few minutes to replace what's melted. While the heat casualties guzzle fluids at higher rates than the normal maximum. And occasionally have to flip over to have their body core temp checked until it drops back into the normal operating range. Then spend the next several hours peeing out the excess fluids. The unconscious ones get a straight ice bath, and two large-bore (really big) needles jammed into veins, and have bags of normal saline poured into them intravenously.
Don't be that guy.
But if your buddy becomes That Guy, rapid and aggressive intervention is the key to proper treatment.


In cold temperatures, you're worried about
* chilblains
* immersion foot
* frostbite
* snow blindness
* hypothermia

This one embiggens too.

Chilblains come from repeated exposure of bare skin to cold temperatures between 60-32°  F..
Skin is red, hot, swollen, and tender. The circulation is compromised.
The treatment is gradual rewarming.
Do not rub or massage affected/injured parts.

Immersion foot comes from repeated or prolonged exposure to wet cold conditions at temps between 50-32° F.
The foot or feet are cold and painless.
Again, the circulation is compromised.
All wet clothing must be removed, the feet dried, and kept dry and warm.
Untreated, it can progress to blisters, ulceration, and gangrene.
Keep dry and warm, and evacuate to treatment.

Frostbite is when the tissue has actually frozen from prolonged exposure to extreme cold temperatures.
The circulation is absent.
Ears, nose, fingers, or toes and feet may be any color from white to blue to black.
Rewarm gradually, and evacuate to treatment.
Do not rewarm feet if casualty will need to walk. It's less damaging and painful for them to walk on frozen feet than to warm them, and then walk on the damaged feet with sensation (and pain) returned to feet.
Do not rub, massage, apply anything (including not snow, FFS) or manipulate the injured parts in any way.

Snow blindness is when the increased UV at altitude and/or reflected up from snow-covered white ground essentially sunburns and cooks the inside of the eyes.
The eyes will feel gritty and painful.
Treatment is to cover the eyes and protect them from any light, using heavy cloth, or the darkest glasses/goggles available, and evacuate the casualty.
Early treatment is to apply dark glasses/goggles/homemade eyeslit goggles, to prevent further exposure.

Hypothermia is the cooling of the body beyond normal operating range, with increasing seriousness.
Early hypothermia will manifest as shivering, increasing mental and physical slowness and decreased coordination, confusion, and slurred speech. They may actually not feel cold, and remove articles of clothing like a hat or jacket.
Moderate hypothermia will progress to glassy eyes, stiffness, shallow breathing, weak pulse, and unconsciousness.
Severe hypothermia will present as complete stiffness/rigidity, irregular heartbeat, and possibly sudden death.

Treatment in early or moderate cases is rapid rewarming by removing wet clothing, placing victim inside a sleeping bag, giving warm fluids if conscious, and evacuation to medical treatment.

In severe hypothermia cases, monitoring the patient's pulse and respirations should be frequent, but rewarming in the filed is not indicated, because moving chilled acidotic blood around their body and back to the heart may cause severe cardiac dysrhythmias and cardiac arrest, which cannot be treated or managed well in the field.
Treat severe hypothermia cases as gently as raw eggs, and evacuate them to definitive medical care and treatment as rapidly as possible.

Hot, cold, and critters can all cause severe injury or death.
Historically, even in wartime casualties are distributed as 20% battle-produced, and 80% other causes, especially related to environmental factors.
As they are much more predictable than random injuries and deaths when bullets and shell fragments are flying, prevention of these kinds of medical problems is fairly simple and highly recommended.

Mother Nature is an indifferent bitch.
Don't you be hers.

3 comments:

Anonymous said...

You've touched on it a few times, but the best way to treat injuries is to not get injured in the first place. Part of which is be be capable of doing what you need to do (military standard, if you haven't been tested to do something you're not authorized to do it so no Pvt Pyle you can't tie your own shoes). Mostly though it comes down to don't be stupid.

If you can't climb it don't start. If can't ID the snake give it a wide berth. If you're in over your head Wade to shore...or drown.

Anonymous said...

Stupid phone which let me preview and couldn't edit.

Above was Mark D, because I try to ID myself when I comment.

RandyGC said...

Thanks. Good review for me and hopefully a life saver for newbies to this.

I was once in a factory where it got extremely hot. The safety guys had placed color charts over the urinals in the men's room (could not attest to placement in the ladies room) that showed the different colors of urine, and what to do if your output matched a level on the chart, including "call (plant safety emergency line) if you are peeing this color".

Kinda weird at first, but my thought is that the plant safety guys were zeroed in enough on their job responsibilities (send everybody home to their families at the end of the shift) not to care if it was weird.