Hypothermia has always been one of the most persistent threats in the outdoors, but in recent years it has taken on a new relevance. As more people venture into the backcountry, as weather patterns grow increasingly unpredictable, and as emergency response systems face longer delays, the risk of cold‑related emergencies has quietly but steadily increased. Despite advances in gear, clothing, and public awareness, hypothermia remains a leading cause of preventable wilderness morbidity. It is a condition that does not discriminate by season, experience level, or terrain. It can strike on a winter summit attempt or a spring hike, during a river crossing or a sudden rainstorm, on a windy ridge or a shaded valley floor. In 2026, understanding hypothermia is not just a matter of medical knowledge — it is a matter of leadership, preparation, and sound decision‑making in environments where help may be hours away.

At its core, hypothermia is a simple concept: the body loses heat faster than it can produce it. Yet the simplicity of that definition belies the complexity of how hypothermia develops and how quickly it can progress. In the wilderness, the human body is constantly negotiating with the environment. Wind strips heat from exposed skin. Wet clothing accelerates cooling through evaporation and conduction. Fatigue reduces the body’s ability to generate warmth. Injury immobilizes the patient, preventing the muscular activity that helps maintain core temperature. Even mild dehydration or inadequate nutrition can impair the body’s ability to stay warm. Hypothermia is rarely the result of a single factor; it is the cumulative effect of multiple stressors acting together.

One of the most important shifts in wilderness medicine over the past decade has been the move away from rigid temperature‑based classifications of hypothermia toward a more functional, observation‑based approach. In remote environments, responders rarely have access to accurate thermometers, and even when they do, environmental conditions can make readings unreliable. Instead, modern wilderness responders focus on what the patient can do — their level of shivering, their coordination, their mental status, and their ability to communicate. These functional indicators provide a far more practical and reliable way to assess the severity of hypothermia in the field.

Early hypothermia often begins subtly. A person may feel chilled, clumsy, or unusually tired. Their hands may lose dexterity, making it difficult to operate zippers, buckles, or gear. Shivering becomes noticeable, then vigorous. Thinking slows. Decisions become harder. In many cases, the patient may not recognize these changes in themselves. They may insist they are fine, even as their condition worsens. This is one of the most dangerous aspects of hypothermia: it impairs judgment at the very moment when clear thinking is most needed.

As hypothermia progresses, shivering — the body’s primary mechanism for generating heat — begins to slow or stop. This is not a sign of improvement but a sign of exhaustion. The body has depleted its energy reserves and can no longer sustain the muscular activity required to stay warm. Confusion deepens. Speech becomes slurred. Coordination deteriorates. The patient may stumble, fall, or behave irrationally. In severe cases, the patient may become unresponsive, with slow, shallow breathing and a weak pulse. At this stage, the risk of cardiac dysrhythmias increases significantly, and even minor jostling can trigger life‑threatening complications.

In the wilderness, hypothermia rarely occurs in isolation. It often accompanies trauma, dehydration, exhaustion, or environmental exposure. A hiker who twists an ankle and cannot walk may become hypothermic simply by sitting still on cold ground. A paddler who capsizes in cold water may develop hypothermia even after reaching shore. A climber caught in a sudden storm may become hypothermic despite wearing appropriate gear. Responders must therefore approach hypothermia not as a standalone condition but as part of a broader picture that includes the patient’s physical state, the environment, and the operational realities of the situation.

The first priority in treating hypothermia is to remove the patient from the conditions that caused it. This may mean moving them out of the wind, off wet ground, or into shelter. Even small changes in the environment can significantly slow heat loss. Once the patient is protected from further exposure, responders must address wet clothing. Wet layers draw heat away from the body at an alarming rate, and replacing them with dry layers — or at least adding insulation — is essential. In many wilderness scenarios, responders must improvise with whatever materials are available: sleeping bags, jackets, rope bags, emergency blankets, or even natural materials like pine boughs.

Rewarming strategies depend on the patient’s condition. A person who is alert and able to swallow can benefit from warm, sweet drinks that provide both heat and energy. Heat packs or warm water bottles placed near the armpits, chest, and back can help raise core temperature. Body‑to‑body warming may be appropriate in some situations, though it requires careful consideration of safety, comfort, and group dynamics. For patients with moderate or severe hypothermia, gentle handling is critical. Cold myocardium is extremely sensitive, and rough movement can trigger dangerous heart rhythms. Responders must move slowly, deliberately, and with clear communication.

Insulation is one of the most powerful tools in hypothermia management. The goal is to trap warm air around the patient and prevent further heat loss. This often involves creating a “hypothermia wrap” or “burrito,” using a combination of vapor barriers, insulating layers, and windproof outer layers. The head and neck must be covered, as these areas account for significant heat loss. In prolonged care scenarios, responders must also consider pressure points, moisture buildup, and the patient’s comfort over time.

Prolonged field care is a reality in many wilderness settings. Evacuation may be delayed by terrain, weather, or limited resources. In these situations, responders must shift from rapid intervention to sustained management. This includes monitoring the patient’s mental status, breathing, and circulation; providing ongoing insulation; offering warm fluids when appropriate; and maintaining morale. Leadership becomes as important as medical skill. A calm, organized responder can stabilize not only the patient but the entire group, preventing panic and ensuring that tasks are carried out efficiently.

Hypothermia prevention is far easier than hypothermia treatment, and it begins long before an incident occurs. Proper clothing, layering strategies, nutrition, hydration, and weather awareness all play critical roles. Responders and outdoor leaders must cultivate a mindset of anticipation, recognizing early signs of fatigue, cold stress, or deteriorating conditions. Turning back early, adjusting pace, or adding layers before someone becomes chilled can prevent emergencies entirely. Group dynamics also matter. Teams that communicate openly, check on each other regularly, and maintain situational awareness are far less likely to experience hypothermia incidents.

Case studies from wilderness SAR operations consistently highlight the same themes. Many hypothermia incidents begin with small decisions: a hiker who pushes on despite feeling cold, a group that underestimates the impact of wind and rain, a patient who becomes immobilized after an injury, or a team that delays intervention because they assume the patient will “warm up once we get moving.” These scenarios underscore the importance of early recognition and decisive action. Hypothermia rarely improves on its own. Without intervention, it almost always worsens.

In the broader context of wilderness medicine, hypothermia represents a unique intersection of physiology, environment, and leadership. It challenges responders to think holistically, to balance medical priorities with operational realities, and to make decisions that account for both the patient’s condition and the team’s safety. It demands improvisation, creativity, and adaptability. And it reinforces the fundamental truth that in the wilderness, the environment is always part of the patient.

As we move through 2026, the importance of hypothermia awareness and management continues to grow. With more people exploring the outdoors, with climate patterns shifting unpredictably, and with emergency response systems stretched thin, the responsibility falls increasingly on responders, outdoor leaders, and recreational users to recognize and manage cold‑related emergencies. NWLI’s commitment to realistic, field‑grounded training ensures that students are not only taught the science of hypothermia but also the practical skills, judgment, and leadership required to manage it in the real world.

Hypothermia is not just a medical condition. It is a test of preparation, awareness, and decision‑making. It is a reminder that the wilderness, for all its beauty, remains an environment that demands respect. And it is a challenge that responders must be ready to meet — with knowledge, with skill, and with the calm, steady leadership that defines the best of wilderness medicine.