Wilderness Medicine

A

• Accidental Hypothermia - Staging and Active Rewarming

  Use Swiss staging by core temperature and mental status; prioritize gentle handling, airway and ventilation with warmed oxygen, and active internal rewarming for moderate to severe cases.
• Avalanche Burial - Resuscitation and Hypothermia

  Avalanche burial combines asphyxia, trauma, and hypothermia. Survival depends heavily on rapid extrication and airway status. Resuscitation decisions incorporate burial duration, airway patency, core temperature, rhythm, and lethal trauma. A deeply hypothermic victim with a patent airway and potentially survivable injuries may warrant prolonged CPR and transport to an extracorporeal life-support center.

E

• Exertional Heat Stroke - Cold Water Immersion First

  Core temperature over 40 C with CNS dysfunction requires immediate whole body cold water immersion when feasible; cool first, then transport while managing airway and electrolytes.

F

• Frostbite - Field Rewarming and tPA Considerations

  Frostbite is freezing injury of tissue caused by ice crystal formation, endothelial damage, vasoconstriction, and later microvascular thrombosis. The priorities are preventing refreezing, rapid water-bath thawing when refreezing can be avoided, pain control, wound protection, and early specialty evaluation. Severe injuries may benefit from time-sensitive thrombolytic or vasodilator strategies in experienced centers, while definitive amputation is usually delayed until tissue demarcation unless infection or

H

• High Altitude Illness - AMS HACE HAPE Management

  Acute altitude illness includes acute mountain sickness, high-altitude cerebral edema, and high-altitude pulmonary edema. Symptoms are driven by hypobaric hypoxia after ascent, and severity can progress rapidly. Stop further ascent when illness develops. HACE and HAPE are emergencies requiring immediate descent whenever feasible, supplemental oxygen, and condition-specific treatment; prevention centers on gradual ascent and selective prophylaxis such as acetazolamide.

L

• Lightning Injury - Triage and Resuscitation

  Lightning injury can cause simultaneous cardiac and respiratory arrest, transient neurologic deficits, burns, blast trauma, tympanic membrane rupture, and delayed ocular or neurologic complications. Scene safety comes first. In a multiple-casualty lightning incident, reverse triage is appropriate because apparently lifeless victims may have a better chance of recovery than expected if ventilation and CPR are started promptly.

M

• Marine Envenomation - Jellyfish Sting Care with Vinegar and Hot Water

  Jellyfish stings cause immediate painful linear skin lesions and, depending on species, can produce severe systemic toxicity. Current first-aid guidance prioritizes scene safety, monitoring for anaphylaxis or shock, and mechanical removal of visible tentacles. Hot-water immersion is useful for pain after tentacles are removed. Vinegar should not be treated as a universal remedy because benefit varies by species and some topical agents can increase nematocyst discharge.

N

• Nonfatal Drowning - Airway and Ventilation Algorithm

  Prioritize airway and ventilation with spinal precautions when indicated; give oxygen, consider CPAP or intubation for hypoxia, and observe for delayed pulmonary edema.

S

• Snakebite Pit Viper - First Aid and Antivenom

  North American pit-viper envenomation can produce progressive local swelling, pain, ecchymosis, coagulopathy, thrombocytopenia, and systemic toxicity. Field care should minimize movement, remove constricting items, and expedite transport. Do not cut, suck, ice, apply electric shock, or use a tight arterial tourniquet. Antivenom is indicated for progressive local injury, significant hematologic toxicity, or systemic effects, with serial examinations and laboratory monitoring guiding repeat treatment.

W

• Wilderness Anaphylaxis - Epinephrine Field Management

  Wilderness anaphylaxis requires rapid recognition and immediate intramuscular epinephrine despite limited resources or prolonged evacuation. Airway swelling, bronchospasm, hypotension, or rapidly progressive multisystem allergic symptoms should trigger treatment. Remove the trigger when possible, position and support the patient, repeat epinephrine if symptoms persist, and evacuate because biphasic or refractory reactions may occur.