Wilderness medicine: Your guide to treating illness or injury in the great outdoors

As a pediatrician accompanying friends, family, or youth groups, or because of coincidental proximity to accidents, we may be looked on to provide initial medical care for injured or sick children (or adults) in a wilderness setting far from our usual practice, and far from our usual comfort zone.

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The purpose of this article is to help you to provide care for persons with a serious injury or illness, as well as to describe common illnesses and injuries often seen in wilderness settings.

Scope of the problem

It has been estimated that over 49% of all individuals aged 6 years and older (approximately 142 million persons) living in the United States participated in outdoor recreation in 2012. In that year, US citizens took approximately 12.4 billion outdoor excursions.¹

Data from summer camps, hikers, and outdoor programs dealing primarily with children report that the most common medical problems encountered are injuries (sprains, fractures, lacerations, foot blisters, burns), gastrointestinal illnesses, and upper respiratory illnesses, most of which are minor injuries and illnesses.^2,3 A study of hunters presenting to the emergency department (ED) in western Colorado noted that the chief presenting complaint was injury or trauma (45%), followed by medical illnesses (31%) and “other” problems (24%).⁴ The most common illness was cardiac, and the cause of all deaths was cardiac.⁴

The National Outdoor Leadership School, an organization mostly involved in extended backcountry travel and mountaineering, reported an average of approximately 1 significant illness and 1 significant injury per 1000 persons per day in the field.⁵Acute gastroenteritis and upper respiratory infections were the most common illnesses, whereas sprains and strains were the most common injuries. Approximately 50% of the injuries occurred while hiking. In this series, out of the 46 injuries reported, 18 injuries occurred while cooking, 7 while eating, and 4 while playing games in camp. Only 17 injuries occurred while mountaineering. Notably, serious injuries are almost twice as likely to occur in camp than while mountain climbing! The most common causes of emergency evacuations were sprains, fractures, dental emergencies, and tick fever.⁵

Assessing the patient and the situation

As you approach a scene, you must be alert to assess not only the patient but also the situation for ongoing dangers, such as rock fall, wild animals, and poison ivy. A quick overall impression of the scene is important. Are there 1 or multiple patients; are they very sick/hurt; or are they not very sick/hurt? A quick initial assessment should be made of each patient, looking for immediate threats to life, by checking the ABCDs (airway, breathing, circulation [pulse], and disability [head and spine control if needed]). Vital signs should be noted and recorded, if possible, because trends are important (a notebook and pen are necessary parts of the first-aid kit), including airway patency; gross breath sounds; respiratory rate and effort; heart rate; color; and level of consciousness. Obvious threats to life, of course, should be addressed immediately.

A head-to-toe assessment should then be done by observation and palpation, but clothes usually should not be removed or cut off because transport to an ED may be delayed for many hours. Inspect and palpate the patient’s head, face, neck, spine, chest, abdomen, pelvis, and all 4 extremities, noting deformity and/or tenderness, blood, or other abnormalities. A history should be obtained, if possible; medic alert information on bracelets, necklaces, and tattoos observed; and last intake/output noted. Head and spine precautions should be observed if the patient lost consciousness or the mechanism of injury indicates a need for caution. The spine can be “cleared” if the patient is alert and oriented times 4; is not intoxicated; denies pain or tenderness over the entire spine (and is not distracted by pain elsewhere); and has normal movement of all 4 extremities (see “Resources for physicians: Assessing a patient in the wilderness”).⁶

After the complete assessment, injuries should be addressed and then the patient reassessed. Continued monitoring of vital signs is important. Of course, if there are serious injuries or signs of shock, if the heart rate increases more than 30 beats per minute with standing, if the radial pulse is not palpable (this correlates with a systolic blood pressure of <80 mm Hg), or if the vital signs are not improving, the patient should be urgently evacuated.

NEXT: Treating head and spine injuries

Head and spine injuries

Initial stabilization of head and spine can be obtained by kneeling with your knees on either side of the patient’s head. This keeps the physician’s hands free to assess the patient. A cervical collar can be improvised with a jacket, knapsack, or a commercially available aluminum splint (that can be folded, bent, and shaped for necks or extremity splints) from a first-aid kit. Techniques for moving a spine-injured patient, or “log rolling,” are well known but unfamiliar to many pediatricians. These can be viewed on the Internet (see “Resources for physicians: Log rolling a spine-injured patient”). A patient with a spinal injury should be stabilized but probably not moved until a search-and-rescue team with proper training and equipment has arrived. A patient with head injuries with loss of consciousness may need to be evacuated. Consider accessibility to and complexity of evacuation, and proximity to healthcare. Making this decision early is prudent.

Closed extremity injuries

Extremity injuries should be evaluated, but obviously a definitive diagnosis cannot be made in the field. Injuries should be inspected, palpated, and evaluated for color (circulation), sensation, and movement. Any constricting bands (rings) should be removed. Injuries of the shoulder and arm usually can be treated with a sling or by pinning the sleeve of a long sleeve to the shirt in the chest area. Immobilizing the arm against the chest wall makes a very good splint. Marked angulation should probably be corrected in the field, something most pediatricians may be uncomfortable with, but this correction improves pain control and allows for better splinting.⁷ Gentle traction distally, with an assistant applying counter traction proximally, will correct the angulation. This has been shown to have negligible risk of creating further injury.

Recommended: Many childhood fractures are treated incorrectly

Assessing perfusion, circulation, and sensation distal to the injury should be done before and after the correction. Lower-extremity fractures obviously make self-evacuation difficult. These can be splinted with a sleeping pad wrapped around the leg and then blown up, if this type of pad is available. Splints of any type should be well padded. All extremity injuries should be repeatedly assessed for proper circulation, sensation, and movement.

Open wounds

Wound hemostasis can be achieved by direct pressure in most situations. Pressure points are no longer recommended. Tourniquets are recommended as the primary intervention to control life-threatening arterial bleeding. A tourniquet should be at least 4 cm wide, and should be used with a windless device of some sort (otherwise sufficient pressure cannot be achieved to overcome arterial pressure). A standard belt cannot be pulled tight enough to overcome arterial flow. Most limbs can tolerate up to 6 hours of ischemia. Hemostatic material can be carried in a first-aid kit to achieve hemostasis in areas not amenable to direct pressure or tourniquets, such as the neck. Impregnated gauze is the most widely used substance.⁸

An open wound should be cleaned as soon as possible to reduce the risk of infection. Wounds should be cleaned by irrigation under pressure. Every first-aid kit should contain a syringe with an 18-gauge needle, which will provide enough irrigation pressure to overcome the adhesive forces of introduced bacterium.⁹ Irrigation volumes of 50 mL to 100 mL per cm of laceration have been recommended.¹⁰ Potable water is adequate for irrigation; sterile water is not necessary.⁸

Clean and even dirty wounds (a wound in the axilla or groin, or a wound presenting longer than 6 hours after wounding) can probably be safely closed in the field after thorough irrigation. Large or contaminated wounds (a wound impregnated with organic material, or a wound already infected) should be left open, packed with wet-to-dry dressings, and allowed to close by secondary intention or with delayed primary closure. Of course, sterile techniques are impossible in a wilderness setting, but primary closure with sutures, staples, wound closure strips, or cyanoacrylate tissue adhesive is usually feasible after the wound has been thoroughly irrigated. Large and deep wounds should be irrigated and packed open with a sterile dressing, to be closed later in the ED. Weight and size of suture or staple kits are a problem, so wound closure strips and tissue adhesive may be more practical to carry in a first-aid kit.

Burns

The burning process should be stopped by immediately cooling the burn site with water and continuing for at least 30 minutes.¹¹ Clothing and constricting bands should be removed. Rings should be removed, even if the hands are not injured, because subsequent edema may cause problems. If the face is burned, the airway has to be assessed. Size of the burn should be estimated using the “rule of nines” or using the patient’s palm and fingers as an estimate of approximately 1% of total body surface area. The burn should be washed and it may be covered with a gel dressing, a topical antibiotic, or honey.¹² Covering wounds reduces pain and evaporative fluid losses.

Hydrating the patient is critical. Elevate, and have the patient gently and regularly move burned areas to reduce edema. Emergency evacuation is important for burns of more than 10% of body surface area; deep facial burns; if there are signs of airway injury; deep burns to hands or genitals; or circumferential burns.

NEXT: Treating cold and heat injuries

Acute chest pain

Acute coronary syndrome (ACS), including myocardial infarction and unstable angina, is a common cause of deaths in wilderness settings.⁴ The Wilderness Medical Society lists 4 medications that they believe are recommended by evidence-based studies to reduce risk of death with ACS in the field: aspirin, nitroglycerin, clopidogrel, and beta blockers.⁷

The society’s recommendation is to give 4 tablets (81 mg chewable) aspirin immediately and then once daily until the patient is evacuated to an ED. Nitroglycerin 0.4 mg tablets may be given sublingually every 10 minutes if the radial pulse is palpable in a standing position and there are no signs of hypotension. Nitroglycerin reduces pain and relieves pulmonary edema. Clopidogrel, a platelet inhibitor, is given as an initial loading dose of 300 mg, followed by 75 mg daily until evacuation to the ED. The beta-blockers metoprolol or atenolol (25 mg) are given every 6 hours, beginning 30 minutes after onset of chest pain and repeated every 6 hours even if pain improves. Beta-blockers should not be given if heart rate is less than 60 beats per minute; the pulse is not palpable in a standing position; or if the patient is short of breath or wheezing. When preparing a first-aid kit, however, weight and size and expiration dates of multiple medicines must be considered carefully.

Patients should be instructed in the first minutes of chest pain to cough if they feel like they are about to faint. Coughing repeatedly and deeply may prevent loss of consciousness during episodes of bradycardia or ventricular tachycardia. Resting the patient is ideal, but rapid evacuation to an ED is important. If care from emergency medical services is not practical because of location and remoteness, the patient may need to self-evacuate by walking slowly.⁷

Altitude illness

Travel to elevations above 2500 meters (8200 feet) is associated with risk of 1 or more forms of acute altitude illness: acute mountain sickness (AMS), high-altitude pulmonary edema (HAPE), and high-altitude cerebral edema (HACE). Some susceptible individuals may develop AMS or even HAPE at elevations as low as 2000 meters (6500 feet). Symptoms of AMS are nonspecific and may be difficult to differentiate from viral illness, but include headache plus 1 or more of the following symptoms: nausea/vomiting, fatigue, lassitude, dizziness, and difficulty sleeping. If symptoms are mild, patients may remain at their current altitude and use nonopiate analgesics for headache and antiemetics for gastrointestinal symptoms.

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Descent to lower altitudes (300 to 1000 meters), however, remains the most effective treatment. If symptoms are moderate in severity or progressing, or neurologic symptoms develop (ataxia, altered mental status, or severe lassitude), the patient may have HACE and should descend in elevation immediately. Dexamethasone should be administered (intravenous, intramuscular, or by mouth) as 8 mg loading dose followed by 4 mg every 6 hours until symptoms resolve. The pediatric dose is 0.15 mg/kg/dose every 6 hours.¹³

Cold injury and illness

Hypothermia should be treated by removing the patient from wind and, if possible, removing wet clothes. The patient should be given as much insulation as possible with such items as double sleeping bags, coats, and insulating pads under them, and, if possible, wrapped in a foil emergency blanket, tarp, tent, or other waterproof covering to prevent convective and conductive heat loss (see “Resources for physicians: Hypothermia wrap”). Hot water bottles may be placed inside the wrap to provide added heat, but generally having another person inside the wrap is not helpful. More rapid warming may induce ventricular fibrillation.⁷

Frostbite should be treated with skin-to-skin warming if it appears superficial; that is, if the skin is pale but the underlying tissue is still soft and pliable. If deep frostbite is suspected because the skin is white and hard, the patient should be evacuated immediately. Patients with frostbitten feet may self-evacuate. All patients with deep or superficial frostbite should be given ibuprofen to inhibit thromboxane production and care should be taken not to allow thawing and then refreezing because this causes much more severe tissue damage.⁷

Heat illness

Heat illness ranges from mild symptoms such as heat cramps (widespread muscle cramps) and heat syncope (transient loss of consciousness with rapid spontaneous return to consciousness) to heat exhaustion (with sensation of intense thirst, weakness, anxiety, and dizziness), and then to heat stroke (severe heat illness associated with core temperature greater than 104°F, altered mental status, seizures, and coma). Children with a decreased thirst mechanism and less active sweat glands are more prone to heat illness.

Obviously, high environmental temperature and humidity are predisposing environmental factors that increase the risk of developing heat illness. Heat illness is more easily prevented than treated in the field. Wetting the patient, removing to shade, fanning, and giving cold drinks are helpful. If the patient has mental status changes, immediate evacuation is indicated. Continued hydration should be done awaiting evacuation.

NEXT: Bites and sprains

Animal bites

In the United States, 99% of all venomous snakebites are from snakes in the pit viper family, including rattlesnakes, copperheads, and water moccasins (cottonmouths).¹⁴ Rattlesnakes are native to all states except Alaska, Hawaii, and Maine. Copperheads are found in the eastern half of the United States. Water moccasins are found in the Southeast and the South. Bites occur primarily during the summer months when the snakes are more active, and the clinical effects are more severe in children.¹⁵ Rattlesnake bites may not involve envenomation in as many as 20% to 30% of bites. Because rattlesnake venom is basically made up of digestive enzymes, when a patient is envenomated, rapid pain and swelling ensues. Any restrictive clothing or rings should be removed; the extremity should be immobilized and maintained at the level of the heart as possible; and the patient should be evacuated to an ED.¹⁶ Commercially available “rattlesnake bite kits” are dangerous and should never be used.⁷

Read more: More pearls from the trenches

Bat bites should always be treated as a rabies exposure. Bats have extremely small teeth, and a wound may not be easily visible. The wound should be washed thoroughly to reduce viral inoculum, and the patient should be immediately evacuated to an ED for administration of rabies immune globulin and rabies vaccine.⁷

Plant dermatitis

Poison ivy and poison oak are common plant-induced dermatoses in North America caused by exposure to the plant resin urushiol. This resin is rapidly absorbed and binds to subcutaneous fat. Therefore, washing must be done in the first 10 minutes to be effective. Topical steroids applied in the first few hours after exposure may have some efficacy, but once the dermatitis has appeared, oral prednisone is indicated at a dose of 1 mg/kg/day (maximum dose, 60 mg/day) for 14 days and then tapered by 10 mg every other day.⁷

Foot blisters

Foot blisters are the most common injury faced in outdoor settings. Friction between the feet, socks, and shoes causes shearing between the stratum spinosum and overlying layers of skin. Hydrostatic forces cause the space to fill with plasma-like fluid. Pain can then cause abnormal gait patterns, which can lead to secondary overuse injuries.

Foot blisters often can be prevented by wearing properly fitting shoes or boots, which are “broken in,” as well as wearing polyester or acrylic socks (that wick moisture away from the feet) under wool socks, and aggressively treating “hot spots” by taping with duct tape, moleskin, and hydrocolloid or hydrogel adhesive bandages.

Blisters larger than 5 mm should be drained with sterile technique, by puncturing at the base and leaving the roof intact. This improves pain control and also reduces complications and risk of secondary infection. An antibiotic ointment may be applied and then the wound covered with a hydrocolloid or hydrogel patch or moleskin.

Ankle sprains

Ankle sprains are among the more common injuries in the wilderness. They can be difficult to deal with when one is far from a paved road. An ankle sprain may be taped to give enough support to allow a patient to self-evacuate (see “Resources for physicians: Taping ankle injuries”). A durable tape is best. Duct tape can be used but it is difficult to remove and wrinkles in the tape can cause blisters. Cloth tape is the usual tape used, but it sticks poorly to skin, so the foot and ankle may be wrapped with “prewrap.” This allows the tape to stick well and be removed easily.

Obtaining help in the wilderness

A cell phone signal may be obtained in many remote areas by hiking to a mountaintop. A satellite phone can be rented for about $70 to $80 a week or purchased for about $700, but weight, size, and cost may be challenges. A small device can be purchased to be paired with a smart phone, which then allows the phone to send text messages through a satellite. These are much smaller and lighter than a satellite phone. Such devices can be purchased for approximately $150 to $300, but yearly subscription fees may be required.

NEXT: Preparing the first-aid kits

First-aid kits

A kit for a day hike, an extended backpacking trip, or a trip to a foreign country will obviously vary in content, size, and weight. The following supplies are recommended for any basic kit, based on data from what is actually used in the field¹⁷:

·      Equipment. Disposable nonlatex gloves; irrigating syringe; small scissors; tweezers; several safety pins; optional small bottle of sterile eyewash (for irrigating wounds); alcohol swabs (for cleaning equipment); small notebook and pencil; foil emergency blanket; and aluminum foam splint.

·      Dressings and wound care. Twelve adhesive bandages; roll of 2-inch cloth tape and prewrap for ankle sprains; roll of 2-inch paper tape; duct tape; roll of 3-inch gauze; 3-inch elastic bandage; moleskin; second skin dressings; transparent skin dressings; sterile 4-inch by 4-inch pads; wound closure strips; and tissue adhesive.

·      Medications. Ibuprofen; aspirin; acetaminophen; antibiotic ointment; antihistamine; steroid cream; tincture of benzoin (to assist with taping); optional sublingual nitroglycerine tablets; epinephrine auto-injector; albuterol metered-dose inhaler.

Conclusion

Pediatricians may be called upon to provide medical care in a wilderness environment. The information in this article will help you to prepare for emergencies and to fulfill your role as a physician in an outdoor setting.

REFERENCES

1. Raines S. Participation in outdoor activities hits six-year high. Outdoor Foundation website. Available at: http://www.outdoorfoundation.org/news.foundation.php?news_id=1585. Published August 8, 2013. Accessed April 1, 2015.

2. Elliott TB, Elliott BA, Bixby MR. Risk factors associated with camp accidents. Wilderness Environ Med. 2003;14(1):2-8.

3. Paton BC. Health, safety and risk in Outward Bound. Wilderness Environ Med. 1992:3(2):128-144.

4. Reishus AD. Injuries and illnesses of big game hunters in western Colorado: a 9-year analysis. Wilderness Environ Med. 2007;18(1):20-25.

5. McIntosh SE, Leemon D, Visitacion J, Schimelpfenig T, Fosnocht D. Medical incidents and evacuations on wilderness expeditions. Wilderness Environ Med. 2007;18(4):298-304.

6. Hoffman JR, Mower WR, Wolfson AB, Todd KH, Zucker MI. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma. National Emergency X-Radiography Utilization Study Group. N Engl J Med. 2000;343(2):94-99. Erratum in: N Engl J Med. 2001;344(6):464.

7. Wilderness Medical Society. Forgey WW, ed. Wilderness Medical Society Practice Guidelines for Emergency Medical Care. 5th ed. Guilford, CT: Globe Pequot Press; Falcon Guides; 2006.

8. Quinn RH, Wedmore I, Johnson EL, et al. Wilderness Medical Society practice guidelines for basic wound management in the austere environment: 2014 update. Wilderness Environ Med. 2014;25(4 suppl):S118-S133.

9. Nicks BA, Ayello EA, Woo K, Nitzki-George D, Sibbald RG. Acute wound management: revisiting the approach to assessment, irrigation, and closure considerations. Int J Emerg Med. 2010;3(4):399-407.

10. Chisholm CD, Cordell WH, Rogers K, Woods JR. Comparison of a new pressurized saline canister versus syringe irrigation for laceration cleansing in the emergency department. Ann Emerg Med. 1992;21(11):1364-1367.

11. Edlich RF, Bailey TL, Bill TJ. Thermal burns. In: Marx JA, Hockberger RS, Walls RM, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 5th ed. St. Louis, MO: Mosby; 2002:807.

12. Stewart JA, McGrane OL, Wedmore IS. Wound care in the wilderness: is there evidence for honey? Wilderness Environ Med. 2014;25(1):103-110.

13. Luks AM, McIntosh SE, Grissom CK, et al. Wilderness Medical Society practice guidelines for the prevention and treatment of acute altitude illness: 2014 update. Wilderness Environ Med. 2014;25(4 suppl):S4-S14.

14. Ho CH, Newman EG, Stotts CL. Rattlesnake envenomation. CFP. 2014;13(8):378-379.

15. Cheng AC, Seifert SA. Management of Crotalinae (rattlesnake, water moccasin [cottonmouth], or copperhead) bites in the United States. UpToDate. Updated February 23, 2015. Accessed April 1, 2015.

16. Seifert S, White J, Currie BJ. Pressure bandaging for North American snake bite? No! Clin Toxicol (Phila). 2011;49(10):883-885.

17. Welch TP. Data-based selection of medical supplies for wilderness travel. Wilderness Environ Med. 1997;8(3):148-151.

RESOURCES FOR PHYSICIANS

Here are several links to helpful how-to videos and instructions for treating emergencies that occur in the wild away from medical facilities.

Assessing a patient in the wilderness:

www.youtube.com/watch?v=hXQAmx2AYIk

Log rolling a spine-injured patient:

http://m.wikihow.com/Logroll-an-Injured-Person-During-First-Aid

Hypothermia wrap:

www.youtube.com/watch?v=uxOXBE_R3EY

Taping ankle injuries:

www.youtube.com/watch?v=VHzpLzRu8Oc

Dr Auxier is a physician in private practice with Gilbert Pediatrics, Mesa, Arizona. He has nothing to disclose in regard to affiliations with or financial interests in any organizations that may have an interest in any part of this article.