Medicine for Solo Wilderness Travel

COPYRIGHT © ANIL Mitra, 2015 – 2023

Most of my wilderness backpacking has been solo. I have written some considerations for solo wilderness travel so as to improve my preparedness for medical and other contingencies. This might be useful to other hikers for though much has been written on wilderness medicine and rescue, I haven’t come across anything on solo travel. In writing these notes I’ve referred to the 5th edition of Medicine for Mountaineering and other Wilderness Activities, edited by James A. Wilkerson, M.D.

Almost any medical emergency or other problem that arises in a group can arise for the individual. What is different is that the range and effectiveness of responses are severely limited for a single person. If the individual is sufficiently incapacitated response may be severely limited or impossible—the risk for solo travelers is significantly greater than for an individual traveling in a group.

So, while the standard emergency and other situations must be considered, solo travel must especially emphasize attitude, preparation, and precaution. The hiker must understand and be prepared for solo risk. They must adjust some aspects of preparation and hiking and be prepared to accept the inevitable additional risk.

I should make a disclaimer. These notes are written for me, for conditions I’m likely to encounter, and are relative to my knowledge and experience. I’m looking at problems that arise as a result of wilderness conditions and activities. I don’t look at general medical problems that may arise or be adversely affected in the wilderness. I focus on issues for the solo hiker. I have taken over a hundred backpacking trips and I estimate I have spent the equivalent of about two years in the ‘backcountry’; roughly ninety percent of this has been solo. However I must emphasize that I’m not an expert on the subject of these notes. If you use the notes, use them as a supplement to good books—one on wilderness hiking and another on wilderness medicine.

Contents

Preparation

Knowledge

Physical and related preparation

Communication

Precautions

Attitude

Water

Shelter and clothing

Medical kit

Repair kit

Food

Wilderness problems, prevention, and response

Emergency

Sprains and fractures

Acute Mountain Sickness (AMS)

Heat stroke

Cramps

Poison Oak

Bites and stings—snakes, insects, and rabid animals

Animal threat and attack

Preparation

Since precaution is all important preparation must emphasize both medicine and general outdoor skills. This chapter will consider knowledge, preparation, and general skills.

Knowledge

The area visited and its conditions; personal limitations and health as well as medications for already existing conditions; wilderness experience that enables knowledge of strategies-needs-risks; adequate knowledge of emergency response and medicine.

It is obviously essential to acquire this knowledge before travel. A group leader or individual traveler should, in particular, be knowledgeable and experienced in outdoor medicine. It is a good idea to review and refresh knowledge and skills before every trip.

Physical and related preparation

Conditioning; general health should be good; gear-food-fluids appropriate to anticipated conditions; adequate medical supplies. Teeth should be in good condition.

Communication

I don’t take communications devices (cell phones rarely have service in wilderness areas) but perhaps I should take some kind of radio communication; I fill out permits even when not required—this provides some record to authorities; it is a good idea to tell family or friends your plan of travel and exit date.

Precautions

In additions to basic do’s and don’ts of group travel, the main don’t concerns risks that are heightened in an individual situation. These are discussed in a general way immediately below and specifically in the next chapter, Wilderness problems, prevention, and response.

Attitude

Attitude is important, first as attitude in potentially dangerous situations in which a key element is estimating needs-resources and planning (rather than mere reactivity). Some situations are of course so immediate that this estimating / planning may be instant and intuitive but still there is an art to appropriate calmness and use of anxiety. Practice of meditation—sitting and in action—may be useful in forming healthy emotive-cognitive response; this practice need not be formal but a good teacher or book will be very helpful. Anticipation and some degree of thinking through potentially dangerous situations may be helpful in assessment-in-the-moment (that is in part what writing on wilderness medicine is about).

A second aspect of attitude is that of knowing that travel alone has greater risks than group travel—and that there is some appropriate balance between accepting such risks and taking precautions. Knowing why I like to travel alone and experience are important in determining this balance. It is safer to tell someone your planned exit date but if you don’t tell someone your plan you aren’t bound by one.

Water

Inadequate water intake—even when it is not life threatening—can cause numerous problems. Examples are constipation and confusion. The latter can lead to life threatening situations. Sufficient and frequent water intake is important. I will not make recommendations but note that I weigh about 180lbs and like to drink 3 quarts (US) a day in cool not particularly dry weather when not hiking or doing anything else particularly physical. I add about 1 quart every 5 miles and more depending on how much warmer and drier it is.

Water borne parasites are killed by boiling (5 min), chemical or radiation treatment, or filtering. I’m almost always good at taking this precaution. On my most recent trip I did drink untreated water after a storm—I thought that any parasites would be washed out but though I didn’t get infected I don’t recommend this.

Shelter and clothing

Shelter and clothing are essential to prevent exposure. An umbrella or hat can prevent sunburn and overheating (heat stroke).

Prolonged exposure to temperatures lower than the body can result in hypothermia if thermal protection (clothing, shelter) are inadequate. Any temperature less than about 80 F carries some risk.

One high risk situation for hypothermia is around 50—60 F, when you do not feel particularly cold but become wet from rain or sweat from exertion. Layering helps prevent overheating and a rain shell that breathes air and moisture will encourage evaporation of sweat. On my recent trip I walked a whole day in driving rain and my Columbia OmniTech kept me perfectly dry—I was immensely pleased—it outperformed my Gore-Tex jacket. A shell also provides protection against wind chill. Adequate caloric intake and hydration are important. Head cover is important because about 60% of heat loss can come from an exposed head (when the rest of the body has good cover). In driving rain at temps of 60 F or less the best strategy may be to erect your tent (avoiding places where water can collect or flow) and stay in your sleeping bag except to eat and eliminate body waste. Clothes and sleeping bag may be kept dry with a plastic liner (trash bag) inside a stuff sack. This has always worked in the past but on my recent trip my clothes got wet. I hadn’t changed the plastic liner in a few trips and it had developed holes. I used to replace critical liners every trip and I plan to resume this practice. Plastic liners also provide protection against stove fuel and diesel exhaust (travelers who use primitive buses will appreciate this).

One should be able to recognize hypothermia. It is a situation in which the body is unable to generate heat at the rate at which it is being lost. The core temperature drops below its normal level of around 98 F and may keep dropping. If steps are not taken while exposure continues, body temperature continues to drop and the end result may be death. So it is important to recognize early signs. The first sign is likely to be shivering. Shivering is a ‘mixed’ sign—it is a precursor to hypothermia but also shows that the body has not yet lost its heat regulating ability. Continued shivering, however, is not good and if hypothermic conditions continue shivering may become severe. There may be mild confusion, likely the result of hypoglycemia that starts as sugar reserves are depleted. In fact, hypoglycemia may contribute to hypothermia because sugar reserves are diminished at outset and because hypoglycemic confusion may impede recognition and response. Obviously hypoglycemic conditions and individuals are at high risk. Prevention is clearly best but if you find yourself shivering steps to prevent further loss of heat should be initiated. This includes hot high carbohydrate food (perhaps with sugar supplement) and hot fluids, tent, dry clothes, and sleeping bag. If there is no tent / bag—this will not normally happen to the prepared hiker—build shelter and a fire if possible; go to shelter if it is not too far. In moderate hypothermia, shivering will be severe, gait unsteady, and you will experience confusion. The situation should not have come this far but if it does it is a definite emergency—if your body becomes even colder you will become so confused as to be beyond the point of responding.

If you are planning on water travel, a life jacket and—at water temperatures less than 80 F (27 C)—a wet suit are crucial. Without these partial submersion is an emergency. If you do become partially submerged you have two options (1) get to land or flotation as soon as possible and (2) use any flotation and tuck your knees under your chin to minimize heat loss. At 40 F you have as little as 10 minutes (less if you consider the initial involuntary gasping and deep breathing response) but probably no more than 20 minutes before confusion sets in. Here are some further time estimates from Hypothermia safety: at 32.5 F exhaustion / unconsciousness in 15 minutes and death in 15-45 minutes; at 32.5-40 F 15-30 minutes / 30-90 minutes; at 40-50 F 30-60 minutes / 1-3 hours; at 50-60 1-2 hours / 1-6 hours; at 60-70 2-7 hours 2-40 hours; at 70-80 F 3-12 hours 3hours-indefinitely. Once you get to land it is essential to regard yourself as hypothermic and take the actions described above and below.

Prevention is obviously most important. (1) Recognize situations in which hypothermia is likely and avoid them. I don’t mean to avoid cold and wet situations but to have adequate protection if such situations might arise. (2) Have adequate clothing and gear. Synthetic fibers and wool are best at heat retention and have some effectiveness even when wet (if soaking, wring out as much water as you can). As noted above it is effective to use layering and vapor breathing barriers to prevent wetness from rain and sweat. In extremes inner moisture proof garments and outer waterproof gear is effective: the insulating layers are protected from both sweat and precipitation (perfect dryness is difficult to achieve but this combination is effective). Tent and sleeping bag should be adequate protection against wet-cold. (3) Have an adequate amount of food and fluids; high carbohydrate content is important and should be taken before exposure.

In extreme cold or in a snow storm a four season tent and adequately rated sleeping bag are essential. Moisture from breathing can condense and freeze on the tent fabric and block oxygen supply—a dangerous, life-threatening situation. A tent with fly or tarp may help prevent this problem. I study tents and talk to experienced sales persons at my local store before buying my tents. This is an advantage over catalog buying (another advantage is that you see what you are buying but of course one could see the item in a store and buy it from a catalog). At sub freezing temperatures breathing inside a sleeping bag can cause condensation in the bag and freezing at the outside surface (resulting in less oxygen—and also dangerous and life-threatening) and wetness in the bag (poor insulation). Head cover (thermal cap or warm clothing item) will prevent bag condensation. Some cold weather campers use a ‘snorkel’ for breathing while completely covered by the sleeping bag. I haven’t done this so don’t know how well it works.

If you do become wet and / or are losing more heat than your body is generating you should consume calories, warm food and fluids. Even so you may face a difficult decision—to stay or leave for lower altitudes and / or adequate warmth and shelter. Once when this happened the decision was agonizing but I didn’t rush it. I could not keep warm so I decided to go lower. Once I made the decision I ate a good meal and packed quickly. This was when I was younger and my pack with cold weather gear, camera, lenses, tripod, and a month of food weighed 90lbs. It was probably over 110lbs wet. The adrenaline made it seem like 30lbs and made my balance exquisite. Side comment: adrenaline is interesting; on another occasion I hiked easily during daylight hours on a wet cold day but a week later when I did the same trip in comfortable conditions the hiking seemed quite a bit harder.

Obviously tents and rain gear should be seam sealed and in good repair.

Good boots are important to ankle support and so to injury prevention. Boots that are not worn in are more likely to cause blisters. A liner sock reduces friction, provides extra warmth, and reduces wear on the main sock. In warm weather, though, I wear one pair of socks and high-tech ‘sneakers’. I have occasionally carried a 50lb pack while wearing only sandals on my feet. Fortunately my ankles are strong.

Medical kit

Medications to consider. (1) Pain for comfort and to aid travel when injured. Consider narcotic pain killers as life saving in case of injury. (2) Balanced salt tabs to maintain electrolyte balance. (3) Antihistamines to counter non-anaphylactic reactions. An epinephrine kit if you are at risk for anaphylaxis or just want to be prepared. There is more than one kind of kit out there. If I took one I’d consider the EpiPen. (4) Antibiotic and corticosteroid ointments or creams. Broad spectrum antibiotics if you know when to use them and appropriate dosing and course. (5) All prescription medicines including allergy medications. (6) Benzodiazepines—these are not necessary for a healthy individual but may appropriately reduce incapacitating anxiety treat alcohol withdrawal (obviously if you know you are physically addicted you choose a medical rather than a wilderness setting to withdraw). I don’t take ‘benzos’ hiking but some books recommend it.

A first aid kit may contain (1) Band aids, medical tape (to cover small wounds and to prevent blisters), sterile gauze pads, and bandaging material. (2) Ace bandage for sprains. (3) Needle and blade which can be sterilized in boiling water or an open flame. (4) Inflatable splint. (5) Bear spray option.

Repair kit

A repair kit (tent, clothing, pack, stove) can be combined with the first aid kit.

Food

Lack of food is not an emergency of the magnitude of lack of water or lack of shelter and dry clothing. However, in addition to the obvious reasons, food is important to warmth, energy, and attitude. A hiking trip is not the best time to withdraw from caffeine. My hiking trips are fun. They are a time for inspiration. They are a time of health. That they are strenuous at times—but not all the time—is part of this and by design. Good healthy food helps.

Wilderness problems, prevention, and response

Exposure, hydration and other issues discussed above will not be repeated. I will discuss (a) special wilderness risks, (b) avoidance and prevention, and (c) what responses are available to the individual. A reminder: these notes focus on problems I have or am likely to face and not on all potential problems. Discussion is sketch for these reasons as well as the fact that I didn’t see a need to reproduce what is already in books on outdoors medicine.

Emergency

The essentials of prevention are to avoid risk of life threatening injury—an individual cannot perform self-CPR. However an individual can do a self-Heimlich maneuver—to be prepared read up and take a course. And an individual can self rescue from (a) a physically threatening environment or circumstance and (b) an injury that is partially incapacitating. It’s important to be aware of potential threats, to know emergency response and first aid, to be fit, to know how to climb, to navigate and so on.

Sprains and fractures

Reading what can happen in the way of fractures and dislocations is intimidating. All I can recommend is use of splints, perhaps improvised, and pain medications prior to self-evacuation. Open fractures should be cleaned and dressed. In the backcountry, especially when solo, you probably will not accomplish adequate care. Your goal is to be clean; provide support and comfort; get to safety and medical treatment; and have a happy ever-after.

Sprains are best treated by rest, ice (cold), compression, and elevation (the pertinent acronym is RICE). A sprain may be as incapacitating as a fracture and the distinction without x-rays difficult. Bad sprains should be treated as fractures until medical treatment is available.

Consider having a narcotic pain reliever for use to help with ‘self-evacuation’. I’ve done this in Mexico where, when I traveled there, prescriptions weren’t required for codeine. I didn’t use the codeine and I didn’t bring it back to the states.

Acute Mountain Sickness (AMS)

When I got to about 13,000ft in the San Juan Mountains in Colorado in early September 1983, it was 4 pm. I had been hiking all day and for the last half hour I felt a bad headache and nausea (I was eating peanuts and M&M’s and it’s only recently that I’ve been able to tolerate that combination again). I set my tent, threw in my sleeping bag and pack and jumped into the bag. I woke up refreshed next morning. I didn’t realize at the time that I had Acute Mountain Sickness.

Mild to moderate AMS feels like a bad hangover—headache (may be severe), nausea, and possibly vomiting. It may be expected or worsened with too rapid elevation increase (50% of hikers will experience symptoms when going rapidly from sea level to 14,000ft), high altitude (as little as 6000ft), and exertion. Prevention includes gradual acclimatization to altitude (a few thousand feet a day), adequate hydration, a light high carbohydrate diet, and rest; 125 mg Acetazolamide two times a day helps prevention and acclimatization. Some individuals never acclimatize; this is thought to be genetic. Response (treatment) includes going to a lower elevation, hydration, high carbohydrate diet, and rest. Dexamethasone is useful for treatment (1mg to 9mg per day in divided doses every 6 hours—you should develop a plan with your MD); interestingly, high doses of this drug are helpful in anaphylaxis (IV 20mg) but in the wilderness epinephrine is preferred. Ibuprofen is more helpful than aspirin for headaches in AMS.

Individuals can develop unsteady gait in AMS. AMS is common and self-limited but recognizing and responding to it is important because it can develop into the dangerous conditions of high altitude cerebral or pulmonary edema. See a good book on how to deal with these bears.

Heat stroke

Cause—the body’s heat regulation (cooling) is overwhelmed by extended exertion in extreme heat. Prevent—by avoiding the causes and recognizing very early signs of hotness and confusion. Signs—sweating stops or is excessive, temperatures as high as 104 F, redness of skin, nausea, confusion. Treatment—stop exertion, cool down by any means available (wet a shirt, dip in a pool etc).

Cramps

Cramps are often associated with sweating from exertion and high temperature. Restore water and electrolytes—two salt tabs chewed, not swallowed whole, can be followed by sixteen to twenty four ounces of water. I’ve needed to do this but once. The treatment was effective within fifteen minutes.

Poison Oak

It is important to be able to recognize poison oak so as to avoid it. Even if you have not reacted to it in the past you may develop a reaction. If exposed, the poison oak oils (urushiol) should be washed away immediately. This can be done with Technu. Oral antihistamines and topical corticosteroid cream can help. If you expect a severe reaction you should walk out and seek medical treatment—preferably an IM corticosteroid in severe cases for one or more days until the reaction goes down (one time my lower right leg ballooned up to about 1.5 to 2 times its normal size it took IM prednisone 40mg prescribed by my MD for three days to get the reaction under control).

Bites and stings—snakes, insects, and rabid animals

Snake bites are best avoided. It really helps if you know when and where to expect poisonous snakes. The only poisonous snakes I encounter in Northern California are rattlesnakes. They tend to seek rocky trails exposed to sun afternoons on cool to warm days. I don’t know what I would do if bitten. Rest is indicated till treatment is available but you must walk out and this may take time. Rattlesnake bites are usually not fatal to healthy adults and a restricting band will prevent venom flow and enhance local damage. Everyone seems to agree that the only possibly useful incision and suction device is the Sawyer extractor but many think that even this is useless. Every one agrees that mouth suction is useless.

If allergic you may have an anaphylactic reaction to insect bites even hours after the bite. It is important to have an epinephrine kit and to know how to use it—and to have an individual strategy worked out with your physician. I don’t carry a kit—perhaps a risk but I have not yet had anything other than the inevitable local reaction to insect stings.

If an animal is rabid it will probably behave strangely (aggressively). If bitten, it is crucial to wash the wound with copious amounts of water (flowing is better, soap is good too but many hikers take no soap with them) and walk out and seek medical treatment. It is unlikely that you will be able to catch the animal.

Animal threat and attack

Black bears usually avoid humans except when surprised or if they have come to expect left over food, e.g. around campgrounds and hunter’s camps. These camps are best avoided. Food should always be hung by rope from tree branches (15ft from ground, 5ft from the trunk) away (downwind) from ‘camp’. Wild black bears even sows with cubs are rarely aggressive to humans. If they are the best approach is to behave aggressively—shout, wave arms, walk toward the bear usually scares the bear. Running away, acting dead are not advised for response to black bears.

I don’t care what brown bears do because I don’t frequent brown bear habitat. But I might some day and then this information might be useful. Brown bears are aggressive and encounters may be avoided by being noisy; partially eaten carcasses and places with vultures circling above should be avoided; in an encounter be unthreatening, avoid eye contact, walk slowly backward. If attack seems imminent playing dead may be effective and you should not ‘come back to life’ until sure the bear has left and then some more. Curl up, cover your head with your arms to protect your head from a bite or swipe.

When I hiked in Glacier National Park I was traveling in a group. Apparently there are no known attacks on groups of more than four people and a single individual is far more likely to be attacked than two to four. Solo hikers should know this. We carried ‘bear bells’. Along the trail, a local was collecting berries. He made fun of us hikers with our bells. He was solo and had no bell. I bet he wears seat belts when he drives though.

Mountain lion attacks are rare but usually unprovoked. Threatening behavior, looking tall and big, opening your coat wide may frighten of the lion; running invites attack; if attacked fight back—‘the lion is looking for a meal, not a fight’.