Wilderness Medicine

WFA Scope of Practice Document Update

Tod Schimelpfenig — Wed, 26 Dec 2012 16:58:00 GMT

The Wilderness First Aid (WFA) course, widely taught by numerous providers, can be burdened with unrealistic expectations of the topics and skills that can be taught in a basic layperson first aid program.

In 2010, sensing a need to clarify what first aid skills and knowledge are realistic and practical for a WFA provider representatives from the major wilderness medicine educators created a WFA Scope of Practice (SOP) document. The SOP is in essence a job description of what a WFA provider should know and what skills they should and should not be able to perform.

The original writing group convened this fall to review and update the WFA SOP. Two years have passed since the original document and with the publication of the WFA Skills Retention Study a review was timely. The latest version articulates the minimum skills and knowledge base for a WFA provider.

Another ongoing project is a review of the medical evidence supporting WFA practices. Several representatives of wilderness medicine schools are on this Wilderness Medical Society working group. We hope to see publication of this work in 2013.

This SOP document is not binding on anyone. It is not crafted as a curriculum. It reflects the consensus of a group of providers who created and have taught this course to tens of thousands of students over three decades and who are actively engaged in the practice of wilderness first aid. It is our hope that it provides some guidance to those who teach WFA and guidance for the outdoor program manager deciding on the appropriate certification for their staff and for the consumer who is choosing between different certifications.

We invite observations and comments, which can be submitted to any member of the working/writing group, and for organizations/individuals to indicate their support for this work by adding their signatures.

Cordially

Tod Schimelpfenig

Curriculum Director

NOLS Wilderness Medicine

December 2012

Hantavirus in Yosemite National Park

Paul Auerbach — Sun, 30 Sep 2012 20:10:00 GMT

by Paul Auerbach

Our National Parks are a treasured heritage, and one of the ways in which we appreciate the outdoors. Millions of visitors flock to the parks in order to camp, hike, climb, swim and most of all, appreciate the wonder and natural beauty of America. As with any other outdoor setting, there are risks of injuries and illnesses. A recent cluster of cases of hantavirus pulmonary syndrome apparently originating from Curry Village in Yosemite National Park this summer points this out.

Hantaviruses (such as the sin nombre virus) cause a syndrome characterized by a combination of fever, lung failure, kidney failure, shock, and bleeding. The viruses are spread in the excreta of rodents; in the United States, hantavirus pulmonary syndrome (HPS) has been linked to the deer mouse (Peromyscus maniculatus) and white-footed mouse (P. leucopus), as well as to the cotton rat (Sigmodon hispidus) and rice rat (Oryzomys palustris). The animals shed the virus in saliva, urine, and feces. Aerosols are the most likely route of transmission from rodents to humans. Insect bites have not yet been implicated in transmission. The virus found in the U.S. is not known to cause human-to-human transmission.

The deer mouse is a creature that is adept at squeezing through very small openings. In the case of Curry Village at Yosemite, mouse nests have been found in the wall spaces of tent cabins, and mice have tested positive for the virus from around the park.

HPS has been reported in most states west of the Mississippi River, as well as in a few eastern states. In Louisiana and Florida, two hantavirus species, bayou virus and Black Creek virus, have been identified. A person infected by the virus has an incubation period of 1 to 6 weeks after exposure, and then suffers from fever, muscle aches, headache, cough, dizziness, abdominal pain, nausea and vomiting, and diarrhea for a few days; this is followed by difficulty breathing, mottled skin on the limbs, shock, and, sometimes, bleeding. In the U.S., approximately a third of victims die.

Most victims have had an interaction with rodents, such as when cleaning a barn or capturing the animals. Unfortunately, there is not yet any specific therapy beyond supportive care. Because a person with hantavirus infection may become seriously ill at a rapid rate, it is important to promptly bring any suspected victim to medical care.

To avoid unnecessary exposure to hantavirus, it is recommended that wilderness enthusiasts observe the following precautions:

keep food and water covered and stored in rodent-proof containers
dispose of food clutter
spray dead rodents, nests, and droppings with disinfectant before handling (wear gloves)
clean and disinfect cabins and other shelters thoroughly before using
don’t make camp near rodent sites
don’t sleep on bare ground
burn or bury garbage promptly
discard food that looks like it may have been chewed upon by rodents
use only bottled or disinfected water for campsite purposes.

Reprinted with permission from Healthline.com

Wilderness First Aid Retention Study

Tod Schimelpfenig — Sun, 09 Sep 2012 18:26:00 GMT

Wilderness First Aid (WFA) courses are taught by multiple individuals and programs. They have become a standard for people working and recreating in the outdoors. Are they effective? Can the participants remember the information? Can they perform the skills?

To investigate these questions NOLS Wilderness Medicine Institute (WMI) conducted a research project to measure retention of WFA skills and knowledge. There is literature on skill and knowledge retention in CPR and first aid, but nothing we could find on WFA courses.

The research was conducted with our colleagues at the University of Utah; Scott Schumann PhD, Jim Sibthorp PhD and Rachel Collins MS. At the conclusion of an open enrollment WFA course the study participants were given a written exam and an assessment of their confidence in their ability to perform their WFA skills. At either 4, 8 or 12 months post course they returned to complete a scored skills-based scenario, familiar to anyone who has taken a WMI WFA course. They also repeated the WFA knowledge and self-efficacy measures they took at the original training. You can read the detailed study methodology, results and limitations at the Journal of Wilderness and Environmental Medicine http://wemjournal.org/.

Our findings are not surprising.

• We quickly forget what we do not practice. The longer the time from training, the more we forget.

• Written tests do not correlate with performance on practical tests.

• Our opinions on our competence may not correlate with our practical performance.

The study participants demonstrated poor skill proficiency when taking vital signs, obtaining a medical history, and conducting the focused spine assessment (a selective spine immobilization protocol). These results are consistent with studies that show first aid knowledge and skills, or any skills or knowledge for that matter, deteriorate in the absence of repeated practice.

The poor skill retention seen in this study brings an interesting perspective to the complaints we hear about the burden of biannual recertification of WFA/WFR. The American Heart Association suggests practicing medical professionals refresh their BLS skills more frequently than every 2 years. We cannot assume that laypeople will retain their skills any better than practicing professionals. Bravo to those organizations with ongoing training for their staff.

The study did not look at teaching competency, but it does beg these questions. The content may be basic first aid, but in our (albeit biased) opinion the volume of stuff in a WFA requires a skilled educator to have any chance for competent graduates. WFA courses are taught by skilled educators and outdoor medicine practitioners, and they are taught by people who obtain a WFA instructional credential online with no verification they can teach effectively, have ever touched a patient or spent a night outdoors. Buyer beware.

These results raise the question of the appropriate role for this certification. The WFA course was designed as an introductory layperson first aid course for those close to help or assisting a more highly trained provider and is described in this context in the Scope of Practice document. It has unfortunately evolved into a wilderness trip leader credential.

We must also pause and ponder all the content people want crammed into this course. Of everything we could teach, what needs to be learned by a layperson to practice wilderness first aid? We have grown to expect more from this course than we can deliver in 16 hours of instruction.

WMI doesn't find these results discouraging, nor did we choose, as can happen in product research, to bury the negative results. We empirically assessed and now report our outcomes. We have already revised our WFA curriculum. We cut unnecessary content detail, including the focused spine assessment. We found more practice time in a busy agenda. We are developing other educational tools to increase retention. We're excited to continue to evolve an important curriculum that is accurate, realistic and practical.

Cordially

Tod Schimelpfenig

Curriculum Director

NOLS Wilderness Medicine Institute

Reference: Schumann SA , Schimelpfenig T , Sibthorp J , Collins RH . An examination of wilderness first aid knowledge, self-efficacy, and skill retention . Wilderness Environ Med . 2012;23:281–287

September 2012

Building a Wilderness First Aid Kit

Julie Anderson — Mon, 23 Jul 2012 13:57:00 GMT

Re-posted with permission from Wilderness Medical Associates International.

Walking through the first aid aisle at your local outfitter store can be overwhelming. While there are many excellent prepared kits on the market, often enthusiasts choose to create and specialize their own. Your kit will be different based on where you are camping and hiking. Trips at altitude, near marine environments or canyoning, and desert trekking each have unique needs that would require you augment your kit accordingly.

Below is a “basic kit list,” to which you can add on as your number of adventurers, length of trip, level of training, or destination dictate. An asterisk marks items that you might include for your week-long trip. For your overnight, you can feel comfortable paring down the quantities.

Personal Protection:

Gloves (Nitrile) – Vinyl is too porous, and latex is a common allergen. Bring a few more pair than you think you need. You use one pair of gloves each time you clean a wound, and gloves aren’t designed to be re-used. If your gloves have been in your kit for a long time, check them to make sure they didn’t degrade in heat or cold. Have these easily accessible so that you are inclined to use them when needed.
CPR mask and airway management- you can get a quality mask with a filter for around $12. “Keychain” masks are better than nothing, but have a short life span when put to use. If you have been trained to use airway adjuncts, include some—they are a little bit of weight for a lot of good.
Wound care (probably the most common supplies I use on trips):
1” athletic tape- one roll per person per week for hiking/skiing/climbing trips (really). It’s good for blister prevention, blister covering, ankle taping, and much more.
Gauze/ dressings (4-6) – different sizes and a few nonadherent (great for burns or abrasions).
Adhesive bandages (8)- various styles.
Roller gauze or vet wrap (2)- something to keep the gauze next to the wound that won’t cut off circulation. Vet wrap lasts longer than roller gauze.
Waterproof/ breathable (occlusive) wound dressings (2-3)*- an invaluable addition to wound care if you will be out for a few days. On a clean wound, this can create an environment conducive to healing that lasts a couple days. These are generally 2” x 3” or larger.
Tweezers- invest in a good pair (sharp and pointy), which will only cost a couple dollars more than a cheap pair.
Small magnifier- for wound cleaning. Be sure you have a reliably bright light source for wound exploration.
Wound cleaning*- a 60cc syringe (check the local feed store) with an irrigation tip is cheap and lightweight and gives better pressure than anything we could improvise.
Trauma shears (1)- there are some cool tiny ones (4”) on the market that only cost a few dollars and work great.
Blister care- Moleskin, foam, gel pads, or whatever your flavor. Duct tape should not be used on open blisters.

Musculoskeletal injuries:

Compression wrap(s)- 3” works great for supporting ankles or knees.
Aluminum foam splint (1)
Triangular bandages (2)- these are multi-functional.

Over the counter medications:

Pain management- ibuprofen and acetaminophen work in different ways. Bring what you prefer, and pack a few grains of rice if you have bottles of tablets. It keeps the tablets from becoming a paste in moist conditions.
Gastrointestinal meds*- antacids such as calcium carbonate, anti-diarrheal such as loperamide, or whatever works for you.
Antihistamines- diphenhydramine for allergic reactions. Epinephrine injectors are prescription only and should be carried by those who require them.
Topical antibiotic cream*- good for small, shallow wounds. No need to get a huge tube, and beware of antibiotic allergies among your group.

Random other things and debatable items:

Your Field Guide of Wilderness & Rescue Medicine
Timepiece
Extra waterproof zip bags- these can be packaged with your SOAP note, pencil, and local emergency numbers.
Stethoscope*- If you are comfortable listening to lung sounds, I would recommend this for aquatic or altitude trips.
Oral glucose gel*- If you have honey in your camp kitchen, it will suffice. Many coffee shops have honey packets available as condiments- perhaps pick up a few with your purchase.
Temporary dental filling*- maybe not for a week-long trip, but it’s small, cheap, easy to find in the store, and can turn a trip around to the good easily.
Antifungal cream*- miconazole or clotrimazole would be good for a longer trip.

Comfort care to be carried by individuals, depending on the environment:

Aloe*
Throat lozenges*
Lip balm
Sunscreen
Insect repellant
Contact care
Personal medications- asthma inhalers, etc.

Much of this can be bought at local pharmacies, “feed and seed” stores, grocery stores, or through online retailers.

Pick your vessel. You might be inclined to choose a zippered nylon clamshell with organizer pouches or see-through dividers. Or, if you are an ultralight hiker, you may choose waterproof zip-top bags. For paddling trips, dry bags or dry cases may be preferred if you can keep the inside dry (but I wouldn’t want to haul a dry box on a mountaineering trip!) Regardless of your outside package, it is worth the extra few minutes to compartmentalize your contents by thought- something that makes sense to you, like: big wounds; little wounds and blisters; common pills (like ibuprofen); uncommon pills (like GI meds); etc. I use a vacuum sealer when I am more worried about water seepage or risk management (this makes it inevitable to see if something’s been used, and then program managers know to seek out an incident report or replace stock).

Have a great trip!

*This assumes your survival gear (the rest of the ten essentials) is packaged elsewhere.

When to Use Tourniquets

David Johnson — Thu, 19 Jul 2012 15:09:45 GMT

Re-posted with permission from Wilderness Medical Associates International.

I am not sure that there is a consensus about their use but here is my opinion about tourniquets in remote and hostile environments.

In brief:

1. Learn how to use one and practice with it.

2. Apply to stop bleeding not controlled by well-aimed direct pressure.

3. Use something wide and firm (but not hard) that can apply circumferential pressure. The pressure should be sufficient to stop bleeding. Make sure that it is in good shape and not a knock-off.

4. Place proximally (upstream) and as close to the wound as possible.

5. Don’t release in the field if the patient is in shock, has an an amputated limb, or has a wound site that cannot be monitored for re-bleeding.

6. For a long evacuation, wait an hour before trying to release it. If bleeding starts again, re-secure. Note the time and leave it in place until definitive care is reached or arrives.

7. Under dangerous circumstances, one may be applied before a thorough evaluation is possible. These should be applied to the proximal thigh or arm if there is any question about the location and/or number of wounds. Carefully check the wound when it is safe and feasible. As indicated, leave, reposition, or release it or add a second one proximally.

The following is an explanation of my above opinion. None of this should be misconstrued as a blanket endorsement to buy and carry one on all trips.

Tourniquets have a checkered history and hyperbolic claims continue to muddy the water. Past and current combat experience in the SW Asian theaters has drawn renewed attention to them because injuries to limbs have been a major source of life-threatening bleeding. There, they are being used successfully to control obvious and potentially serious bleeding. In the later case, they are applied before a proper assessment is possible e.g., multiple casualties, continued live fire. The tourniquets used are relatively cheap and can be lifesaving if used properly. As with anything in medicine, nothing works 100% of the time.

In civilian practice, it is relatively rare for death from limb bleeding to occur because properly applied, well-aimed direct pressure failed. Still, tourniquets have their use outside of theater (e.g., mass casualty), so knowing how to use one is important. The relevant questions include what, where and for how long.

What:
A good tourniquet ought to be soft (but not mushy) and wide. Within limits, wider is better. To be effective, the circumferential pressure needs to be sufficient to stop bleeding. A sphygmomanometer (BP cuff) might be ideal except that they usually will not maintain adequate pressure for a long enough period of time. They and similarly designed devices are also bulky and fragile. The gauges break easily and the fabric, bladder and tubes are vulnerable to sharp objects. Cordage, like a rope or 550 cord (parachute), is not a good choice either because of the potential for direct skin and neurovascular injury.

There are a variety of more serviceable versions. Two of them, the CAT (combat application tourniquet) and SOFTT (special operations forces tactical tourniquet), have worked reasonably well in combat. They are compact, inexpensive and easily applied, even by the patient. Their advantages are a tradeoff for effectiveness.

Where:
One needs to have enough remaining limb to hold the tourniquet. I have heard intelligent people argue that they should never be applied to forearms and legs (lower). Generally, I disagree and experience would seem to bear that opinion out. They should be applied as close to the wound as possible. When circumstances prevent a proper assessment for location and number of wounds, some recommend using only the proximal arm (upper) and/or thigh as default positions.

If limb bleeding will not stop, especially with a thigh, another applied in parallel, proximally, may help. Stay off joints. Controlling junctional (e.g., in the groin) bleeding remains problematic.

How long:
People fear tourniquets because prolonged use can lead to neurovascular damage and tissue death. We know that tissue death from impaired circulation can occur in as little as two hours. We also know that tourniquets have been left on for over 16 hours without any notable harm.

Releasing a tourniquet has its own risks and there are circumstances where removal never makes sense. These later would include limb amputation, shock, the inability to monitor the wound or continued bleeding. Intermittently releasing them to temporarily restore circulation has been reported to lead to unrecognized, ongoing blood loss and patient death. On a long evacuation, if the conditions seem otherwise safe, waiting 1 hour before attempting a removal seems like a reasonable time interval. If bleeding starts again, resecure, note the time and leave it in place.

Improper application is an important cause of failure. They can also fail when they breakdown from environmental exposure or from poor construction (e.g., older version knockoff). Always check your equipment before heading out and replace anything questionable. Practice with any tool before you need it for a real emergency.

There are plenty of good resources online that cover step-by-step application and the identification of knockoffs (e.g., date printed on webbing, red tip on the end of webbing).

Treating Severe Heatstroke with an External Cooling System

Paul Auerbach — Mon, 16 Jul 2012 02:19:17 GMT

by Paul Auerbach

Heatstroke is a life-threatening emergency. Therapeutic cooling measures need to be undertaken rapidly in order to prevent the catastrophic organ failure associated with markedly elevated body temperature.

The general dictum is to cool the victim to a normal body temperature, but to take care not to go further into the territory of hypothermia ("overshoot"), which theoretically might create another set of difficulties. But perhaps there is an opportunity now for new thinking regarding cooling a heatstroke victim in dire circumstances.

In an article entitled "Successful Treatment of Severe Heatstroke With Therapeutic Hypothermia by a Noninvasive External Cooling System" (Annals of Emergency Medicine 2012;59:491-493), Dr. Jen-Yee Hong and colleagues report treating a near-fatal case of exertional heatstroke using induced therapeutic hypothermia (33^oC [91.4^oF]) by a noninvasive external cooling system. After treatment, the patient recovered completely, without any neurological sequelae at one year. Prior to cooling, the victim had multi-organ dysfunction, including seizures, lung injury, and coagulopathy (diffuse bleeding).

This is a very important case report, because external cooling devices are much more commonly found these days in emergency departments because they are used to cool patients to protect their brains after they have been resuscitated from cardiac arrest, or in certain other situations where there has been a dangerous period of lack of oxygen to the brain.

The specific device used for this patient was the Medivance Arctic Sun System, which is a noninvasive (no direct access to the bloodstream is obtained) cooling system designed for external temperature management. It circulates chilled water through pads directly adhered to the patient's skin. While this is a single case report and it is impossible to know if merely cooling the patient from a hyperthermic (hot) condition to a normal body temperature would have been sufficient to achieve the same outcome, it is very important to note that going beyond a normothermic condition to a hypothermic (cold) condition did not appear to be harmful and may very well have been helpful, for theoretical reasons noted by the authors.

Outdoor Ed Note: Thanks Paul for this update. The heat waves happening across the U.S this summer are of particular concern for outdoor programs where physical activity is combined with high heat and humidity. Heat stroke can be an immediately life-threatening illness.

Here are a few other good sources about Exertional Heat Stroke (EHS). One critical observation from a number of these articles is advanced recognition of the problem. The person who is "'falling behind' his friends, or collapsing during or shortly after an exercise is suspected to suffer from heat stroke. Staff should be taught to look for these signs and take immediate vigorous steps.

Exertional Heat Illness and Competition - Position Paper by the American College of Sports Medicine (PDF Version)

"Cooling Techniques for Hyperthermia" at Medscape.

Exertional HeatStroke in Israeli Defence Forces (PDF)

Treating Rattlesnake Bites in the Field

Paul Auerbach — Thu, 05 Jul 2012 01:30:12 GMT

by Paul Auerbach

There are two excellent photographs of a rattlesnake bite victim that appear in the June 10, 2010 issue of the New England Journal of Medicine (362;23:2212). Entitled “Rattlesnake Envenomation” in the IMAGES IN CLINICAL MEDICINE feature, they show the bitten finger and the effects on the torso of a man who presented for medical care within a half hour of having been bitten by a rattlesnake. He was treated with antivenom prior to being admitted to the hospital.

The finger image shows the local effect of the venom in this victim, which could have caused tissue destruction (but did not, which is most likely attributable to the timely administration of a sufficient amount of antivenom). The torso image shows the extensive bruising associated with the blood clotting disorder that developed because of the systemic effects of the venom, which combined to prolong bleeding time in this victim. Despite the initial administration of antivenom, the victim continued to develop his bleeding problem, so was administered additional antivenom, which is needed to counteract the venom effects. The patient had a full recovery, which is a credit both to the victim (for promptly seeking medical care) and to the treating physicians, who knew how to properly treat a venomous rattlesnake bite with antivenom.

For the benefit of anyone who might suffer a rattlesnake bite, here are instructions about what to do in the field:

If a person is bitten by a snake that could be poisonous, act swiftly. The definitive treatment for serious snake venom poisoning is the administration of antivenom. The most important aspect of therapy is to get the victim to an appropriate medical facility as quickly as possible.

Don’t panic. Most bites, even by venomous snakes, do not result in medically significant envenomations. Reassure the victim and keep him from acting in an energy-consuming, purposeless fashion.

Retreat out of the striking range of the snake, which for safety’s sake should be considered to be the snake’s body length (for pit vipers, it is actually approximately half the body length). A rattlesnake can strike at a speed of 8 ft (2.4 m) per second.

Locate the snake. If possible, identify the species. If you cannot do this with confidence (which is really only important for the Mojave rattlesnake and coral snake), you might be able photograph the snake using a digital camera, but be careful. Do not attempt to capture or kill the snake, for fear of wasting time and perhaps provoking another bite. Never delay transport of the victim to capture a snake. If the snake is dead, take care to handle it with a very long stick or shovel, and to carry the dead animal in a container that will not allow the head of the snake to bite another victim (the jaws can bite in a reflex action for up to 90 minutes after death). If you are not sure how to collect the snake, it is best just to get away from it.

Splint the bitten body part to avoid unnecessary motion. Allow room for swelling within the splint. Maintain the bitten arm or leg in a position of comfort. Remove any jewelry that could become an inadvertent tourniquet.

Transport the victim to the nearest hospital.

Do not apply ice directly to the wound or immerse the part in ice water. An ice pack placed over the wound (as one would do for a sprain) is of no proven value to retard absorption of venom, but may be useful for pain control. Application of extreme cold can cause an injury similar to frostbite, and possibly lead to enough tissue loss to require amputation.

Application of the Extractor Pump is at best controversial, and is no longer recommended by snakebite experts. The manufacturer claims that if the device is applied according to the instructions provided, it can remove venom without the need for a skin incision. Animal research appears to refute this notion, and even to suggest that by using the device for a rattlesnake bite, it might cause concentration of tissue-toxic venom under the suction cup, leading to a more severe reaction.

If the victim is more than 2 hours from medical attention, and the bite is on an arm or leg, one may use the pressure immobilization technique: place a 2 in by 2 in (5 cm by 5 cm) cloth pad over the bite and apply an elastic wrap firmly around the involved limb directly over the padded bite site with a margin of at least 4 to 6 in (10 to 15 cm) on either side of the wound, taking care to check for adequate circulation in the fingers and toes (normal pulses, feeling, and color). An alternative method is to simply wrap the entire limb at the described tightness with an elastic bandage. The wrap is meant to impede absorption of venom into the general circulation by containing it within the compressed tissue and microscopic blood and lymphatic vessels near the limb surface. You should then splint the limb to prevent motion. If the bite is on a hand or arm, also apply a sling. It should be noted that this recommendation is controversial, in that some experts believe that localizing venom in a single area might lead to an increased chance for tissue damage.

An alternative to the pressure immobilization technique is a constriction band (not a tourniquet) wrapped a few inches closer to the heart than the bite marks on the bitten limb. This should be applied tightly enough to only occlude the superficial veins and lymph passages. To gauge tightness, the rescuer should be able to slip one or two fingers under the band, and normal pulses should be present. The band may be advanced periodically to stay ahead of the swelling. It is of questionable usefulness if 30 minutes have intervened between the time of the bite and the application of the constriction band (or pressure immobilization technique). Again, this recommendation is controversial, for the reasons mentioned in the previous paragraph.

The impression of most snakebite experts is that incision and suction are of little value and probably should be abandoned. It appears that little venom can actually be removed from the bite site. Furthermore, the incision may set the stage for inoculation of bacteria, infection, and a poorly healing wound. Mouth contact with the incision may cause a nasty infection that leaves a noticeable scar; there is also the risk of transmission of blood-borne disease to the rescuer.

“Snakebite medicine” (whiskey) is of no value and may actually be harmful if it increases circulation to the skin.

There is no scientific evidence that electrical shocks applied to snakebites are of any value. On the contrary, there are experiments that refute this concept.

The bite wound should be washed vigorously with soap and water, and the victim treated with dicloxacillin, erythromycin, or cephalexin.

If the victim is many hours or days from a hospital, assist him to walk out or arrange for a litter rescue, allowing frequent rest periods and adequate oral hydration. Splinting and positioning (e.g., elevating or lowering) the bitten part are secondary to any effort to reach a facility where antivenom can be administered.

Watch for an allergic reaction caused by the snakebite. This might cause the victim to be short of breath with or without an airway obstruction from swelling of the mouth, tongue, and throat. Once the victim is in the hospital, the severity of envenomation will be ascertained, and the victim treated with antivenom if necessary. Such therapy must be carried out under the supervision of a physician, because serious allergic reactions to antivenom are possible.

Reprinted with permission from Healthline.com

Hand Injuries Not to Miss

Paul Auerbach — Mon, 11 Jun 2012 01:13:00 GMT

by Paul Auerbach

Hand injuries are common in outdoor enthusiasts. Some of these injuries are easy to diagnose, and others are more difficult, usually because the signs and symptoms are subtle or because the examiner is inexperienced. Emergency physicians, such as me, need to be hyper-vigilant in order to avoid making a mistake in diagnosis. In the field, when there are environmental stresses, poor lighting, noise, and perhaps even danger, it is even more difficult to make the diagnosis.

A recent article in the European Journal of Emergency Medicine points out “Four hand injuries not to miss: avoiding pitfalls in the emergency department (18:186-191, 2011). Dr. Philip Yoong and his colleagues discuss ulnar collateral ligament of the thumb injury, Bennett’s fracture at the base of the thumb metacarpal bone, the volar plate avulsion fracture that occurs to the middle phalangeal bone of a finger, and avulsion of the flexor digitorum profundus tendon. Let’s consider practical field aspects of each of these in turn. Remember that these are all injuries that will eventually be referred to a hand specialist, so the point is to suspect these injuries so that they do not remain undiagnosed and under-treated.

The thumb has three bones: the metacarpal (closest to the wrist) and two phalanges. The metacarpophalangeal (MCP) joint is between the metacarpal bone and the closest phalanx. It is stabilized from side-to-side motion by two ligaments—the radial collateral ligament (lateral, or outside: on the side of the radius bone) and ulnar collateral ligament (medial, or inside: on the side of the ulna bone). Injury to the ulnar collateral ligament occurs then there is a force applied that pulls the thumb away from the hand—like hyperextending a hitchhiking motion. This might happen by falling forcefully while holding a ski pole. The term “Gamekeeper’s thumb” describes a chronic ulnar collateral ligament injury caused by the force created by Scottish gamekeepers who broke the necks of rabbits between the thumb and index finger. How does one make the diagnosis? Although this may be difficult because the examination is limited by pain, when accompanied by the appropriate history, one notes that stressing the thumb away from the hand at the MCP joint causes much more motion on the injured than uninjured side. Depending on whether or not the tear is partial or complete, the victim may be treated with immobilization alone or require surgical repair. In the field, this injury should be immobilized and the victim brought to a hand surgeon as soon as is practical.

A Bennett’s fracture is a break in the base of the thumb metacarpal bone. On X-ray, one sees an angled break in the bone that extends into the joint between the metacarpal bone and the trapezium bone, which is a bone in the wrist. If there has been much displacement of the thumb metacarpal bone at the fracture site, then the joint may become unstable, leading later to osteoarthritis with pain and stiffness. Thus, this fracture is best treated with surgery to achieve proper alignment and fixation for healing. How does one make the diagnosis? Any person with a history of injury to the hand who has pain and swelling of the base of the thumb might have this fracture, so the thumb should be properly immobilized and the the victim brought to an emergency facility for X-rays as soon as is practical.

There are three bones that comprise a finger: proximal (close in), middle, and distal (furthest out) phalanges. A volar plate avulsion describes a situation where the joint between the proximal and middle phalanges, known as the proximal interphalangeal (PIP) joint is injured by a hyperextension motion. In this process, a fibrous structure (volar plate) that connects the palm side of the proximal and middle phalanges across the PIP joint is ripped loose to a lesser or greater degree. Depending on the degree of injury, which is determined by examination and x-ray, surgery might be necessary to achieve proper alignment and allow healing. How does one make the diagnosis? With the history of a hyperextension injury, the victim often shows pain on the underside of the PIP joint, swelling, reduced range of motion, and perhaps bruising. If a dislocation at the PIP occurred and was put back into place, this is indicative of the type of injury that would be accompanied by a volar plate disruption. In the field, the joint should be properly splinted and the victim brought to a hand surgeon or emergency department as soon as is practical.

Finally, there is injury to the flexor digitorum profundus tendon. This is the tendon that creates flexion (downward bending) of the finger at the furthest joint (distal interphalangeal [DIP] joint). The injury is created by a force that pulls the tendon (and sometimes some bone with it) off its insertion (attachment) to the distal phalanx. After this occurs, the finger can no longer be flexed. How does one make the diagnosis? The finger may be swollen at the DIP joint and beyond to the fingertip, painful at this location, and perhaps bruised. To diagnose that the tendon doesn’t work, hold the PIP joint straight and ask the victim to try to flex the DIP joint. In the field, the finger and DIP joint should be splinted in a position of function. Prompt referral to a hand surgeon is essential, because if this injury is not repaired with surgery within 7 to 10 days, primary repair may not be possible. This would mean that any further improvement would only happen with more complicated surgery, which is less likely to achieve 100 percent return of function.

Reprinted with permission from Healthline.com

Support for Ankle Sprains

Paul Auerbach — Mon, 04 Jun 2012 01:23:00 GMT

by Paul Auerbach

Sprained ankles are the bane of existence for hikers, trekker, and joggers—indeed for most athletes or anyone who has the opportunity to twist a foot on an uneven service, stepping over a rock, or falling into a hole. The classic first aid treatment is “RICE”—rest, ice, compression, and elevation. The utility of rest is obvious, because it allows the stretched or torn ligaments to heal and avoids a repeat injury. Ice is the application of cold, which helps to limit swelling and pain in the early post-injury hours (usually recommended for the first 24 hours). Compression is generally applied with an elastic bandage (such as an Ace wrap) to limit swelling and perhaps create a bit of stability to the ankle joint. Elevation means trying to keep the injured part at an altitude above the level of the heart, which perhaps lessens swelling and thereby promotes mobility and perhaps healing.

In an article in the European Medical Journal entitled “Acute ankle sprain: is there a best support?”(2011, 18:225-230) authors Gabrielle O’Connor and Anthony Martin looked at acute lateral ankles sprains, which account for 85 percent of all ankle sprains. In an emergency department in Ireland, they peformed a prospective randomized controlled clinical trial to compare the outcomes in terms of ankle function, pain improvement, and return-to-work times in adults presenting within 24 hours of a first-time acute lateral ankle sprains, among three external supports. The three modalities that were compared were a double Tubigrip compression bandage, Elastoplast bandage, or no support (compression). They were able to include 54 patients, who were divided approximately equally between the three groups, across a spectrum of ankle sprains judged to be mild to severe.

In this study, the patients who were treated with Elastoplast bandaging had a tendency to better average ankle function at the times when this was evaluated at 10 and 30 days after the injury, compared to the other two modalities. They also showed a return to work an average of two days earlier. So, while there was not a statistically significant difference in ankle function between the modalities, it appeared that compression was subjectively useful.

What to make of this for the outdoor enthusiast? I think that it confirms the overall clinical impression that there is value for compression, even if it is not a miracle part of therapy. Compression helps limit swelling, which might otherwise cause it to be difficult to fit into boots or other footgear (although the wrap itself will change the foot and ankle dimensions while it is in use). It also somewhat limits motion and provides a bit of stability to the ankle, which is important if the risk factor of continued activity is present. Lastly, decreasing motion also reduces pain, provided that the wrap itself is not too tight.

Reprinted with permission from Healthline.com

Probiotics and Acute Infectious Diarrhea

Paul Auerbach — Tue, 29 May 2012 01:13:00 GMT

by Paul Auerbach

Probiotics are live microorganisms that are purposefully ingested by humans to improve their health—the thought is that probiotics improve “digestive health.” The specific microorganisms are commonly of the genera Lactobacillus, Bifidobacterium, and/or Bacillus. For instance, one or more probiotic preparations may be taken to re-populate the bowel with normal bacteria (in other words, to have the “friendly bacteria” represent more than 85 percent of the bacteria present) after a person takes a course of antibiotics, which strip the bowel of its normal microorganisms. Probiotics have been recommended to diminish the symptoms of irritable bowel syndrome.

A common question is whether or not probiotics are useful as part of the treatment of infectious diarrhea. To attempt to answer this question, Jeffrey Horn, MD prepared a brief article entitled “Do Probiotics Reduce the Duration and Symptoms of Acute Infectious Diarrhea” (Annals of Emergency Medicine 58[5]:445-46, 2011). In this analysis, he reviewed 63 published studies that looked at the effect of probiotic versus placebo or no probiotic on the duration and symptoms of acute infectious diarrhea. Specifically noted were primary outcomes of duration of diarrhea, diarrhea lasting greater than or equal to four days, and stool frequency on day two after intervention.

In this evaluation, probiotics appear to reduce stool frequency and shorten the duration of acute infectious diarrhea by one day. The author notes that these results were obtained when probiotics were used along with standard rehydration therapy. He also notes that probiotics were not associated with any significant adverse effects. No mention is made of whether or not probiotics were administered with or without antibiotics or any other specific therapy, such as an antimotility agent. It is presumed that these were not used, but that the published studies evaluated were limited to the consideration of probiotics versus no probiotics, without other confounding factors.

So, should we add probiotics to the recommendations for treating acute infectious diarrhea? It appears safe to do this and not to pose any harm to the patient. The drugs can be obtained inexpensively compared to the cost of an additional day of diarrhea, if that means a day lost to activities that are important to the patient or that generate revenue. If antibiotics are going to be used to treat infectious diarrhea, until further notice, it makes sense to wait for the antibiotic course to be completed or nearly completed prior to initiating administration of the probiotic(s). For how long should the probiotic be taken? Some people take probiotics every day, so the course of therapy can probably not be too long. At a minimum, it would be recommended to take a dose of the probiotic(s) once or twice a day for at least 7 to 14 days.

Reprinted with permission from Healthline.com

Classroom Medicine

Tod Schimelpfenig — Mon, 07 May 2012 22:52:00 GMT

I recently sat through a wilderness medicine class by a well-meaning instructor who, despite decent credentials, had never cared for anyone in the wilderness. This is just after reading a poorly crafted wilderness medicine text. Instead of listening to the talk I made a list of things that drive me nuts in wilderness medicine education.

At the top of the list is classroom medicine. These are tools, techniques and advice that work in a clean, controlled world and fail in the reality of the field. Years ago we taught, I taught, not to apply warmth to a severely hypothermic patient because they were in "a stable metabolic icebox." Then I knelt next to my first severely hypothermic patient and the shallowness of this advice was clear. I had no illusions I would warm this patient in the field, but not applying heat to stabilize his temperature made no sense. I read advice to keep frozen feet frozen all night by keeping the foot outside a sleeping bag. This fell to the axe of reality when I stared at my own frozen foot in a tent on a cold winter's night. We used to think tourniquets implied amputation and that open chest wounds need to be sealed with three-sided dressings to allow air to escape. This classroom advice did not survive the test of the battlefield. If your skepticism meter is pegging over words of dubious wisdom, ask the instructor if he has ever done this to a real patient. You'll be surprised how often the honest answer is no.

High on my list are inaccurate statements of frequency. If I believed all the tales of drama I hear from someone who heard from someone who heard, I would not leave home without an auto- injector of epinephrine in a hip holster, locked and loaded. If I believed the NOLS incident data history, solid enough to generate multiple medical papers, I can argue that anaphylaxis is rare in the wilderness. But I won't make that argument. A snapshot is not the entire picture. Data is often a matter of context. We don't know the true incidence of anaphylaxis, or many other ailments, in the outdoors. Statements of frequency need to be viewed with healthy skepticism.

In the same vein I recently read that the risk of a lawsuit from reducing a dislocation in the field is high. Based on what cases or data? I've heard outdoor experts say that the most common injury on NOLS courses is a laceration from slicing cheese. The real answer, sprains and strains, is easily accessible in the published literature. When you see or hear numbers, ask for the source, and ask for the conflicting evidence. If the educator is worth his salt he will tell you the breadth of science on this question and why he choose to believe this particular study. Consider any unreferenced number to be junk.

I'm also skeptical of resumes, credentials and endorsements. Resumes can be exercises in creative writing, exaggerating or underselling experience. Credentials often tell us of educational accomplishments, not experience. Endorsements might be earned, but they can also be purchased-- a source of income for an organization willing to sell their name. These badges don't tell us whether the person has ever seen a patient, seen a patient in the wilderness, spent much time in the wilderness or whether they have ever had to make a real decision in the field.

In my upper echelon of molar grinders are statements of absolutes. These often reveal inexperience, not expertise, and as William Osler MD said "are made at the expense of a clean conscience." There isn't an “accepted” splint. There are splints that are crafted based on available resources and splinting principles. There is no single evacuation plan. There is only what we create based on sound plans, sound assessments and sound judgments. There are many lists of classic signs and symptoms, there is rarely a classic patient.

Last, but not least, is the phrase "our curriculum is evidence-based." This is an intriguing statement since quality evidence in first aid is rare, and in wilderness first aid it is almost non-existent. I prefer to say "evidence-informed." It acknowledges that our choices are a blend of science, experience and opinion.

Am I a curmudgeon? Probably. Am I innocent of these sins? Probably not. But I am aware. I'm trying to be virtuous and I do have the good fortune of being surrounded by colleagues who enjoy calling me to task when I slip.

Take care

Tod Schimelpfenig

Curriculum Director

NOLS Wilderness Medicine Institute

May 2012

Ibuprofen and Altitude Illness

Tod Schimelpfenig — Mon, 26 Mar 2012 16:42:00 GMT

I've been receiving emails about the recent online publication of a study in the Annals of Emergency Medicine titled “Ibuprofen Prevents Altitude Illness: A Randomized Controlled Trial for Prevention of Altitude Illness With Nonsteroidal Anti-inflammatories.” the study was highlighted by several of the health blogs and newspapers.

Eighty-six study participants took either ibuprofen 600 mg or placebo three times a day, beginning 6 hours prior to ascent from 4,100 feet (1,240 meters) to 12, 570 feet (3,810 m) in the White Mountains of California. The study looked at the incidence and severity of acute mountain sickness (AMS) as measured by the Lake Louise Questionnaire AMS score.

The ideal way to prevent AMS is to ascend slowly and acclimatize. Some folks don't want to do this, others may not be able to do it, and some folks still need assistance from medications. The standard has been acetazolamide (Diamox) which is well studied and received an endorsement in the recent WMS Consensus Guidelines for Prevention and Treatment of Altitude Illness.

Acetazolamide (Diamox) works by stimulating breathing, which facilitates acclimatization. We don't know how ibuprofen, an anti-inflammatory medication, works in AMS treatment. It might dampen an inflammatory component to AMS. This remains an active area of research.

In the recent study 69% of the people taking placebo and 43% of the ibuprofen group developed AMS. The severity of the AMS score was less in the ibuprofen group, but it did not meet the predetermined level of significance the authors hoped for.

Ibuprofen is appealing because it is non-prescription and readily available. Both medications have their side effects - pick your poison. This study suggest ibuprofen might work faster than acetazolamide, which should be started the day prior to ascent.

I don't think this study knocks acetazolamide (Diamox) from the altitude medication podium. I'm always skeptical of the latest and greatest drug for altitude illness. They come and they go. We need to see this work replicated, controlled for ascent profile, dehydration and other causes of headache and compared head-to-head with acetazolamide.

In the meantime , given no contraindications or adverse side effects,it is reasonable to use Ibuprofen as a non-prescription medication for prevention of AMS symptoms. If you have a history of AMS talk with your doctor about your choice of medication. Acetazolamide, with it's proven effect on acclimatization, and it's ability to smooth out erratic breathing during sleep,might be a better choice for you.

Risk-taking Behavior and Helmet Use in Skiers

Paul Auerbach — Tue, 28 Feb 2012 02:48:03 GMT

by Paul Auerbach, M.D.

The general consensus in the medical community regarding helmet use and skiing (also snowboarding) is that helmets should be worn to prevent or lessen head injuries related to falls and collisions. While a helmet may not significantly lessen deceleration forces upon the brain incurred by a sudden stop at high speed, they almost certainly somewhat soften the blow and are useful to prevent skull fractures. As they become standard equipment for recreational skiing, we will learn more about the psychology associated with their use.

“Risk-taking Behavior in Skiing Among Helmet Wearers and Nonwearers” is an original research article by Lana Ruži?, MD, PhD and Anton Tudor, MD, PhD in a recent issue of Wilderness & Environmental Medicine (22, 291-296, 2011). The objective of the study was to examine differences in on-the-snow ski behavior between helmet wearers and non-wearers. Using a survey taken of 710 skiers, the predictive power for risk-taking behavior was tested for gender, age, educational level, level of skiing, years of skiing, and helmet usage. Independent predictors for overall risk could be correlated with younger age (less than 35 years of age), male gender, higher skiing level, and helmet usage. Significantly higher risk was assessed for male helmet wearers, while this was not seen to be significant for female helmet wearers. The group found to be most prone to risk-taking behavior was the male occasional helmet wearers

It has been shown previously that male skiers generally take more risks than do female skiers. It is new information that wearing a helmet appears to increase risk-taking behavior, perhaps even further, in young males. What should we make of this? Perhaps wearing a helmet contributes to a feeling of invincibility, or creates an impression in the user that regardless of behavior, a helmet will be protective. Skiers and snowboarders should be made to understand that the benefits of wearing a helmet might possibly be neutralized by risky behavior. Risk profiles for high-speed impacts decline with age, but that should not obviate the need for a helmet. The elder brain is less tolerant of injury, and there is a higher likelihood that a significant blow to the head will result in bleeding within the skull.

Perhaps the largest elephant in the room is the notion I have heard offered by some that if one is not wearing a helmet, he or she is more likely to ski with caution, in order to avoid a collision or fall. This sounds good, but has never been proven. Furthermore, despite all best intentions, collisions occur because skiers catch an edge, are impacted by a colliding skier, slip on ice, or due to a myriad other reasons to precipitously strike the ground or a foreign object with their heads. The takeaway here is that a helmet is not a license to throw away caution, but it appears that this may be the interpretation by young, male skiers. We need to inform them otherwise.

Reposted with permission from the Medicine for the Outdoors Blog

Lightning Safety Awareness

Paul Auerbach — Wed, 25 Jan 2012 16:42:00 GMT

by Paul Auerbach

This post relates information learned in a recent issue (Volume 22, Number 3, 2011) of the journal Wilderness & Environmental Medicine, published by the Wilderness Medical Society.

In an article entitled “Lightning Safety Awareness of Visitors in Three California National Parks” by Lori Weichenthal et al, the authors set out to assess the level of lightning safety awareness among visitors at three national parks in the Sierra Nevada Mountains of California.

Having recently enjoyed a wonderful trip to Yosemite National Park (one of the study sites) and gotten caught in a powerful thunderstorm replete with multiple lightning strikes and wind-driven sheets of rain and icy hail, this is timely for me and very important for anyone who spends time outdoors.

There were no surprises in the conclusions derived from this study, but the investigation reinforces the notion that we don’t recall all that we need to know, or may have never fully understood lightning safety in the first place.

For instance, while participants in the national parks knew that lightning is more likely to strike in the afternoon, they were not aware of the dangers of seeking shelter in a small cave or group huddling. Few people understood proper body position, and other than avoiding metal objects or isolated tall trees, the respondents had too many errors (in my opinion) with respect to advice such as avoiding water or thick groves of trees. The authors appropriately concluded that there exist many educational opportunities, which can take many forms, including trailhead awareness placards, park visitor pamphlets, public service announcements, and national park web site education portals.

Here is some information on lightning avoidance from the 5^th edition of the book Medicine for the Outdoors:

1. Know the weather patterns for your area. Don’t travel in times of high thunderstorm risk. Avoid being outdoors during a thunderstorm. Carry a radio to monitor weather reports. Lightning can lash out from many miles in front of a storm cloud, in seemingly clear weather. If you calculate (see above) that a nearby lightning strike is within 3 miles (5 km) of your location, anticipate that the next strike will be in your immediate area. The “30-30 rule” specifies that if you see lightning and count less than 30 seconds before hearing thunder, seek shelter immediately. Since thunder is rarely heard from more than 10 miles away, if you hear thunder, it is best to curtail activities and seek shelter from lightning. Do not resume activities outdoors for at least 30 minutes after the lightning is seen and the last thunder heard.

2. If a storm enters your area, immediately seek shelter. Enter a hard-roofed auto or large building, if possible. Tents and convertible autos offer essentially no protection from lightning. Tent poles are lightning rods. Metal sheds are dangerous because of the risk of side splashes. Indoors, stay away from windows, open doors, fireplaces, and large metal fixtures. Inside a building, avoid plumbing fixtures, telephones, and other appliances attached by metal to the outside of the building.

3. Do not carry a lightning rod, such as a fishing pole or golf club. Avoid tall objects, such as ski lifts and power lines. Avoid being near boat masts or flagpoles. Do not seek refuge near power lines or tall metal structures. If you are in a boat, try to get out of the water. If you are swimming in the water, get out. Do not stand near a metal boat. Insulate yourself from ground current by crouching on a sleeping pad, backpack, or coiled rope.

4. Move off ridges and summits. Thunderstorms tend to occur in the afternoon, so attempt to summit early and be heading back down by noon. In the woods, avoid the tallest trees (stay at a distance from the tree that’s at least equal to the tree’s height) or hilltops. Shelter yourself in a stand of smaller trees. Avoid clearings—you become the tallest tree. Don’t stay at or near the top of a peak or ridge. Avoid cave entrances. In the open, crouch down or roll into a ball.

5. Stay in your car. If it is a convertible, huddle on the ground at least 50 yards (46 m) from the vehicle.

6. If you are part of a group of people, spread the group out so that everyone isn’t struck by a single discharge.

7. If your hair stands on end, you hear high-pitched or crackling noises, or see a blue halo (St. Elmo’s fire) around objects, there is electrical activity near you that precedes a lightning strike. If you can’t get away from the area immediately, crouch down on the balls of your feet and keep your head down. Don’t touch the ground with your hands.

More Lightning Safety Resources on OutdoorEd.com

Lightning Resources

Wilderness Medicine - 6th Edition released

Rick Curtis — Mon, 09 Jan 2012 02:25:00 GMT

I want to let everyone know about the release of the 6th Edition of Wilderness Medicine, the premiere textbook on the subject, edited by our frequent contributor Dr. Paul Auerbach. There are not too many books out there that I personally consider as "classics" in our field (titles like Mountaineering: The Freedom of the Hills comes to mind), for wilderness medicine, this book is a classic. I've used previous editions of this book for teaching first aid and it was one of my core reference books when writing the first aid chapter in The Backpacker's Field Manual. I'm really excited to see this new edition and that there will be an ebook version. At over 2,300 pages it's no wonder that this textbook is widely referred to as "The Bible of Wilderness Medicine."

This is one book that I recommend that every serious outdoor program have on the shelf as the ultimate reference guide. It covers every conceivable aspect of wilderness medicine in articles written by experts from around the world. What makes this book stand out is the combination of the breadth of coverage and its great readability. I try and keep current on wilderness medicine issues, but as a non-physician, reading things like the New England Journal of Medicine often leaves me scratching my head at the super-technical things that I don't have the background for. This textbook, written for both medical professionals and non-medical provides a great balance. Don't let the price tag deter you, any textbook of this magnitude is worth every penny. The book is available from the publisher Elsevier.com as well as on Amazon.com in hardcover and Kindle format and at Barnes and Noble in hardcover and Nook format.

From the Publisher:

"Quickly and decisively manage any medical emergency you encounter in the great outdoors with Wilderness Medicine! World-renowned authority and author, Dr. Paul Auerbach, and a team of experts offer proven, practical, visual guidance for effectively diagnosing and treating the full range of emergencies and health problems encountered in situations where time and resources are scarce. Every day, more and more people are venturing into the wilderness and extreme environments, or are victims of horrific natural disasters...and many are unprepared for the dangers and aftermath that come with these episodes. Whether these victims are stranded on mountaintops, lost in the desert, injured on a remote bike path, or ill far out at sea, this indispensable resource--now with online access at www.expertconsult.com for greater accessibility and portability-- equips rescuers and health care professionals to effectively address and prevent injury and illness in the wilderness!

From Paul Auerbach:

I’m thrilled to let you know that the 6th edition of the textbook Wilderness Medicine, for which I serve as Editor, is now available. The book is the culmination of more than three years’ work, and the publisher (Elsevier) has done a terrific job with the layout. The book contains 114 chapters, including a tremendous amount of information new to this edition.

This is the big reference book for medical and rescue professionals, educators, scientists, explorers, and others with wilderness medicine interests and activities. The depth of topic coverage underlies much of my other writing. The contributors have gone the extra mile to update their previous work, make new contributions, and do their best to create a comprehensive, encyclopedic work. I’m grateful to have had the opportunity to mold this edition, and am particularly pleased that the publisher allowed me to add chapters on matters related to wilderness preservation. I hope you find it an informative, useful, and fascinating book.

Here’s the Table of Contents:

PART 1 - Mountain Medicine

High-Altitude Medicine and Physiology
Avalanches
Lightning Injuries

PART 2 - Cold and Heat

Thermoregulation
Accidental Hypothermia
Immersion Into Cold Water
Nonfreezing Cold-Induced Injuries
Frostbite
Polar Medicine
Pathophysiology of Heat-Related Illnesses
Clinical Management of Heat-Related Illnesses

PART 3 - Burns, Fire, and Radiation

Wildland Fires: Dangers and Survival
Emergency Care of the Burned Victim
Exposure to Radiation From the Sun
Volcanic Eruptions, Hazards, and Mitigation

PART 4 - Injuries and Medical Interventions

Injury Prevention: Decision Making, Safety, and Accident Avoidance
Principles of Pain Management
Taping and Bandaging
Splints and Slings
Emergency Airway Management
Wilderness Trauma and Surgical Emergencies
Wound Management
Improvised Medicine in the Wilderness
Hunting and Fishing Injuries
Tactical Medicine
Combat and Casualty Care
Wilderness Orthopedics
The Eye in the Wilderness
Foot Problems and Care
Wilderness Dentistry
Management of Facial Injuries
Wilderness Cardiology
Wilderness Neurology
Chronic Diseases and Wilderness Activities
Mental Health in the Wilderness

PART 5 - Rescue and Survival

Wilderness Emergency Medical Services and Response Systems
Search and Rescue
Technical Rescue, Self-Rescue, and Evacuation
Litters and Carries
Helicopter Rescue and Aeromedical Transport
Essentials of Wilderness Survival
Principles of Meteorology and Weather Prediction
Jungle Travel and Survival
Desert Travel and Survival
Whitewater Medicine and Rescue
Caving and Cave Rescue

PART 6 - Animals, Insects, and Zoonoses

Protection from Blood-Feeding Arthropods
Mosquitoes and Mosquito-Borne Diseases
Malaria
Arthropod Envenomation and Parasitism
Tick-Borne Diseases
Spider Bites
Scorpion Envenomation
Bites by Venomous Reptiles in Canada, the United States, and Mexico
Envenoming and Injuries by Venomous and Nonvenomous Reptiles Worldwide
Bites and Injuries Inflicted by Wild and Domestic Animals
Bear Behavior and Attacks
Alligator and Crocodile Attacks
Wilderness-Acquired Zoonoses
Rabies
Emergency Veterinary Medicine

PART 7 - Plants

Seasonal and Acute Allergic Reactions
Plant-Induced Dermatitis
Toxic Plant Ingestions
Toxic Mushroom Ingestions
Ethnobotany: Plant-Derived Medical Therapy

PART 8 - Food and Water

Field Water Disinfection
Infectious Diarrhea From Wilderness and Foreign Travel
Nutrition, Malnutrition, and Starvation
Dehydration, Rehydration, and Hyperhydration
Living Off the Land
Seafood Toxidromes
Seafood Allergies

PART 9 - Marine Medicine

A Brief Introduction to Oceanography
Submersion Injuries and Drowning
Emergency Oxygen Administration
Diving Medicine
Hyperbaric Medicine
Injuries From Nonvenomous Aquatic Animals
Envenomation by Aquatic Invertebrates
Envenomation by Aquatic Vertebrates
Aquatic Skin Disorders
Safety and Survival at Sea

PART 10 - Travel, Environmental Hazards, and Disasters

Travel Medicine
Non-North American Travel and Exotic Diseases
Natural Disaster Management
Expedition Medicine
Global Humanitarian Medicine and Disaster Relief
Natural and Human-Made Hazards: Disaster Risk Management Issues

PART 11 - Equipment and Special Knowledge

Global Crimes, Incarceration, and Quarantine
Wilderness Preparation, Equipment, and Medical Supplies
Ultrasound and Telemedicine in the Wilderness
Outdoor Clothing for the Wilderness Professional
Nonmedical Backcountry Equipment for Wilderness Professionals
Ropes and Knot Tying
Wilderness Navigation Techniques and Communication Methods

PART 12 - Special Populations and Considerations

Training for Wilderness Adventure
Exercise, Conditioning, and Performance Training
Children in the Wilderness
Women in the Wilderness
Elders in the Wilderness
Persons With Special Needs and Disabilities
Wilderness and Endurance Events
Ranch and Rodeo Medicine
Wilderness Medicine Education
Medical Liability and Wilderness Emergencies
The Ethics of Wilderness Medicine
Native American Healing

PART 13 - The Wilderness

The Changing Environment
Biodiversity and Human Health
Health Implications of Environmental Change
Wilderness Management and Preservation
Leave No Trace
Space Medicine: The New Frontier
Appendix - Drug Stability in the Wilderness

INDEX

The hard copy book and e-reader versions both come with access to Elsevier’s expertconsult.com