Spring boating season may be here, but water temperatures are still cold enough to cause problems for boating enthusiasts. Adventure Medical Kits’ marine medicine consultant Dr. Michael Jacobs provides tips for surviving cold water immersion.
AMK's A Comprehensive Guide to Marine Medicine inlcudes tips for treating hypothermia.
Don’t fool yourself into thinking the cold water you sail over is dangerous only when it contains pancake ice and glacial runoff; you could be dead wrong. In fact, water temperature as high as 60ºF can kill you just as easily. Fall into cold water without a personal flotation device (PFD; see sidebar below), and you could drown in the span of a few minutes, often within 10 feet of safety. Statistics indicate an incapacitating response that is rapid in onset and prevents individuals from swimming 10 feet to save their lives. Swimming ability does not improve survival.
We now appreciate that sudden immersion in cold water (less than 60ºF) initiates a series of incapacitating reflexes that increase the risk of drowning. Indeed, the most common cause of death from accidental cold-water immersion is drowning, not hypothermia.
The initial response, which affects breathing, heart function, and muscle strength, is called the Cold-Shock Response. This is a series of reflexes that begin immediately upon sudden cooling of the skin following cold-water immersion. The initial phase of the cold-shock response peaks during the first 30 seconds, and lasts just 2 to 3 minutes. During this time, blood pressure, heart rate, and the workload of the heart all increase, making the heart more susceptible to life-threatening rhythms and heart attack. Simultaneously, gasping begins, followed by rapid and deep breathing. These reflexes can quickly lead to accidental inhalation of water and drowning. This rapid and seemingly uncontrollable over-breathing
creates a sensation of suffocation and contributes to feelings of panic. It can also create dizziness, confusion, disorientation, and a decreased level of consciousness.
It is important to realize that this initial phase of the cold-shock response is brief and that your actions during this time can vastly improve your chance for survival.
If you fall into cold water, it is imperative you try to bring your breathing under control while keeping your head above the water; your life depends on it! Try to calm yourself, do not panic, and realize these reflexes will pass. Just keep your head above the water and consciously slow your breathing. Swimmers experience difficulty synchronizing their swim stroke with these breathing changes and can easily inhale water and drown, even in calm seas. It is safer to tread water and maintain airway freeboard – distance from the water level to the mouth and nose. Breath-holding time is also reduced in cold-water immersion, making escape from beneath a capsized vessel more difficult; kayakers have less time to set
up and roll their craft upright.
Over the next 30 minutes, the muscles and nerves in the extremities cool. Swimming becomes arduous, weak, and ineffective. Loss of muscle strength makes it difficult to perform basic survival procedures. Boaters who fall overboard are often too weak to reboard their craft, get into a life raft, climb the ladder of a rescue boat, or simply grasp a rescue line. Victims in cold water quickly lose the ability to rescue themselves or assist in their own rescue. In icy water, you have only 10 to 15 minutes of effective
muscle strength.
If you fall into cold water, be prepared for violent shivering and intense pain. You can help slow your rate of cooling, and increase your survival time, by following these guidelines:
Do not undress. The added weight of clothing and boots will not impair your ability to float. Clothing traps water next to the skin where it is warmed, retarding heat loss; this is similar to the protective effect of a diver’s wet suit. Clothing also traps air, which provides some insulation and buoyancy. If a short swim is your best chance of survival, then remove any extra clothing and footwear to reduce drag and improve agility.
HELP. If wearing a life jacket, assume the Heat Escape Lessening Posture: cross your hands over your chest and press your arms closely to your sides; draw your knees up toward your chest and cross your ankles. This position facilitates maximum heat retention by protecting the most vulnerable areas of the body.
Tread Water. If you don’t have a life jacket, move slowly and tread water using slight movements. Exercise wastes precious energy and accelerates the rate of cooling by increasing blood flow to the extremities. Activity also flushes cold water through protective clothing, increasing heat loss. Avoid long swims. You have a 50-50 chance of successfully swimming half a mile in 50º F water. If you must swim, pace yourself with an easy stroke, such as the breaststroke, that keeps your head and face out of the water.
Get out of the water. Always reboard or climb on top of a swamped or capsized boat and await rescue. Once out of the water, stay out, no matter how cold the air temperature or how chilled you may feel. You’ll survive longer out of the water because the rate of cooling in water is 25 times greater than in air at the same temperature.
Wilderness Medical Society (WMS) member Dr. Gordon Giesbrecht, a noted hypothermia expert, summarizes the sequence of events and how much time you have after sudden unplanned immersion in frigid water:
ONE-TEN-ONE
ONE minute of gasping, when you need to control your breath. TEN minutes of meaningful strength to pull yourself out of the water. ONE hour before you lose consciousness.
Sudden immersion in cold water need not be a fatal event. Understanding the physiology and exercising appropriate actions for self-rescue will greatly improve your chances for survival. Do not be intimidated by cold water, but respect the challenge it presents.
Treatment
Victims who avoid drowning still face the risk of acute hypothermia as the body’s core temperature decreases. If the victim is fully awake and shivering, then treatment for mild to early moderate hypothermia is reliably effective and evacuation is unnecessary. The victim is capable of generating internal rewarming heat by sustained vigorous shivering if given fluids and carbohydrates, but fuel is required for continued shivering. If dry, and insulating clothing is not available, provide an extra windproof vapor barrier by dressing the victim in foul weather gear to minimize heat loss. When practical, wrap the victim like a burrito in blankets, sleeping bag, sails, or sail bag.
Treat hypothermic victims by wrapping them in blankets.
After prolonged cold-water immersion, generally more than 2 hours, it is prudent to evacuate the victim to a medical facility. These patients are perilously close to losing both consciousness and the shivering reflex. They are incapable of rewarming themselves, and they require more aggressive and sophisticated rewarming methods. Careful monitoring is required because of the many metabolic complications arising from advanced hypothermia. Some sailors have been rescued at sea after prolonged cold-water immersion in an apparently stable and conscious state, only to later collapse while walking around the rescue craft or while taking a hot shower. These people are severely hypothermic and have low blood pressure. Their condition will rapidly deteriorate with activity and during any attempt at external rewarming. They must be kept still, in a supine position, and handled gently in order to avoid physically stimulating the heart to change its rhythm or stop beating. During helicopter evacuation, use a litter with straps so the person can remain horizontal and securely bundled. The rotor blades create a wind-chill from the downwash and can increase the level of hypothermia. Dress and wrap the victim properly during transfer.
Types of PFDs
I:Off Shore Life Jacket: Turns most unconscious people face up in the water even in rough seas, often found on ocean-going boats and commercial watercraft.
II: Near Shore Buoyant Vest: Turns some unconscious people face up in the water in calmer water.
III: Flotation Aid: Common for all purpose boating but will not turn unconscious person face up.
Requires treading water to keep face/head out of water; often these are kayaking, waterskiing, or fishing vests.
IV: Throw Device: Usually a boat cushion or life ring.
V: Special Use: This includes devices that don’t fit in other categories, such as some kayak
or windsurfing vests not approved as Type II or IV.
Special note: for kids, vests should have a groin strap to prevent vest flying off when jumping in water. They should also be sized correctly.
For more info: http://www.uscg.mil/ or http://www.usboating.org.
Michael Jacobs, M.D., is the Medical Consultant for AMK’s Marine Series of medical kits. He is also the MedSail Founder and Program Director: Safety at Sea and Medicine for Mariners Conferences; Medical Director, Vineyard Medical Services, Martha’s Vineyard, MA; a USCG Licensed Captain; co-Author of A Comprehensive Guide to Marine (included in most Marines Series kits) and author of MedicineSurvival at Sea, Textbook of Wilderness Medicine.
HYPOTHERMIA: THE COLD HARD FACTS ABOUT WINTER’S DEADLY KILLER
By Christopher Van Tilburg, M.D.
Rescue mission for a lost snowboarder: a bitter-cold, raging midnight storm high above timberline. That was the scene of my first search and rescue call to Oregon’s Mount Hood as a young doctor. After another team located the snowboarder, I scurried from the tempestuous black night to the ski patrol room, where I examined a shivering, huddling young man. He clutched a blanket draped over soaked ski clothes, and held a steaming cup of hot chocolate, too scalding to drink. Fortunately, the snowboarder had been found. But from across the room I could see he suffered from hypothermia and dehydration.
RECOGNIZING THE SYMPTOMS
Hypothermia is a cooling of the body’s core temperature. Every year 600 people in the U.S. die from hypothermia, according to the Centers for Disease Control and Prevention. Mild hypothermia begins with shivering and progresses to lethargy. Moderate hypothermia is dangerous: one has slurred speech, poor concentration, and a staggered gait. Severe hypothermia is a critical condition: the heart, lungs and other organs start to shut down, and extreme mental status changes occur such as the inability to talk coherently, walk properly, or even process thoughts. Bizarre behavior like paradoxical undressing — when a person discards articles of clothing, even though doing so hinders their chances for survival — can occur when the brain gets confused. A well-known example of this condition involved the CNET reporter James Kim. After being stranded for several days with his family in a remote forested area of southwestern Oregon, Kim set off on his own to find help. He was later found in the snow, having succumbed to hypothermia. Media reports said he had removed several pieces of clothing, including his pants. Paradoxical Undressing not only speeds death but it can also put an entire group at risk, because the person suffering from it will inevitably require more attention and resources – at a time when both may be in short supply. Death by hypothermia doesn’t occur instantly, but it does occur rapidly. And often it is the hypothermic person’s partner who notices a problem first.
IMPROVING YOUR CHANCES OF SURVIVAL
Exemplified by snow burial studies, we know that with today’s fleece and nylon-laminate clothing and a well-built emergency shelter, a person can spend an unexpected night in the winter mountain wilderness, even in below freezing temperatures. But beyond one night without proper clothing, food, water and shelter, your odds of survival plummet even if the thermometer doesn’t. And once you get hypothermic, the basic tasks of survival become difficult to complete.
Before you head into the wilds, always make sure you have enough food, water and clothing for an unexpected night out. And carry the tools to build an emergency shelter such as a shovel to dig a snow cave and a space blanket like the Heatsheets Emergency Survival Blanket to act as a covering.
TREATING HYPOTHERMIA
If you do notice even mild hypothermia—you are more likely to see it in your partner—treat it immediately. Change into dry clothing and put on all extra layers. Insulate yourself from the ground. Chemical heat packs do help, if you place them on your torso. Drink lukewarm fluids and eat a snack: calories and fluids are important to generate internal heat, no matter if they are hot or cold. Seek shelter right away and try to keep active. If you can, build a fire. Make sure you pack a survival kit, with a reliable fire starter and signaling mirror for alerting rescue craft. Above all, get help and evacuate from the backcountry as soon as you can.
Also, watch for coexisting frostbite — when your skin actually freezes — which usually occurs on the face, nose, fingers and toes. To prevent frostbite, make sure that all exposed skin is covered and you have proper boots, socks, gloves and a hat. Frostbite is treated by immediate evacuation then rapid re-warming, usually with 40-degree water or fluids. But be extra cautious if you re-warm an extremity in the backcountry to make doubly sure it doesn’t refreeze, which can cause worse damage than walking out with a frozen finger or toe.
To treat the snowboarder in the ski patrol room, I had his friends help him change in to dry clothes then covered him with dry blankets. And I gave him two large cups of lukewarm hot chocolate, which he guzzled down with gusto and perked up. I checked him for frostbite and we fed him whatever snacks we could find. He finally warmed up and we sent him down the mountain.
Chris Van Tilburg, MD, is the editor of Wilderness Medicine Magazine and is also a member of Crag Rats Mountain Rescue, in Hood River, Oregon. Started in 1927, Crag Rats is the oldest mountain rescue unit in the nation.
In October, a solo climberon Washington’s 12,276-foot Mount Adams fell on Suksdorf Ridge, and broke his ankle. It’s just what every climber fears: being alone on a high mountain with a disastrous injury. Unable to walk, he dragged himself down the snowfields. After five days and nights, he was found at 6,200 feet suffering from frostbite and dehydration. He survived on creek water and an eclectic mix of creepy crawlers: ants, centipedes, spiders, mushrooms, and berries.
Sooner or later, if you spend time outdoors, you may find yourself without food or water on a wilderness outing; hopefully it’s just a short distance to your car and you are uninjured. But in survival mode, if you are lost and injured, you may need to eat and drink from the wilds.
You can live several weeks without food. But you won’t last much past five to seven days without water, even fewer if you are in the desert or at high altitude. Finding water is a paramount priority.
Drinking from creeks, like the Mount Adams climber, is probably a risk worth taking in prolonged survival situations. Yes, you can get protozoa infections like Giardia and Cryptosporidium, as well as bacteria and viruses. However, it takes just one day for you to begin to become incapacitated from dehydration.
When you find a source, ideally you should have a means to purify water before drinking. That means boiling, filtering, or chemical treatment. I carry water purification tablets for emergencies: they are compact, light, and easy to use.
Remember, when in the mountains, eating snow can cause hypothermia, because you need to use vital calories to melt it in your mouth first. So you should carry a lightweight backpacking stove to melt water. When in the desert, locating water can be extremely difficult, so if you find a source, consider staying put until you are rescued. If you do get a gastrointestinal infection from drinking backcountry water, see your doctor A.S.A.P.
As for food, if you can’t identify it, don’t eat it. You can get seriously ill from toxins and infections. My friend Greg Davenport, a survival expert, said critters with eight or more legs like centipedes and millipedes are often toxic. He recommends sticking to insects, which have some nutrition, but not much. A typical 100 gm (3.5 ounce) serving of fish, for example, yields 22 g protein, 1g fat and 0g carbos. The same weight of crickets yields 13 g protein, 6 g fat, and 5 g carbos. But that’s a big pile of crickets to scrounge for.
Wild plants—leaves, roots, bark, nuts, seeds, and berries— can be energizing or deadly. Use caution: even a small bite can cause stomach pain, nausea, vomiting, diarrhea, and rashes. Mushrooms can kill you. Davenport said aggregate berries, like thimbleberries, raspberries, and blackberries, are generally safe to eat. Purple, blue and black berries, such as wild huckleberries and cranberries, are 90% edible. Red berries are about 50% edible, so it’s probably best to avoid those, as well as any berry white, green or yellow, which are not edible.
Remember: always take enough water and food (an extra bottle of water and a few extra energy bars) to spend at least one unexpected night in the wilderness. And stash some water purification tablets in your survival kit.
I wanted to advise you of a recent accident that I had while hiking in Northern New York State. I have attached a news article from the New York State Department of Conservation. The article does not specifically mention one of your products but I want to advise you that it helped save my life. I purchased the Thermo Lite Emergency Bivy Sack at Eastern Mountain Sports, and I stayed in this shelter during my long night out. Please read the article attached and be advised that I truly can say that I was glad that I had this with me. This item along with food and staying hydrated kept my body temperature at 97 degrees for almost 18 hours while I was stuck outside, in temperatures that dropped to -23.
