Cold & Hypothermia 101: Hypothermia
Hypothermia, or a core temperature of ≤95°F, affects the brain, making thinking and moving difficult. This makes hypothermia particularly dangerous because a person may not know it is happening and won’t be able to do anything about it. Hypothermia occurs most commonly at very cold temperatures, but can occur even at cool temperatures (above 40°F) if a person becomes chilled from rain, sweat, or submersion in cold water. Hypothermic victims can be divided into two main categories according to the signs and symptoms that they exhibit: mild and severe hypothermia.
Mild hypothermia begins when the body’s core temperature reaches 95°F. At this temperature, a person’s coordination begins to fail and they begin to stumble and shiver severely. Besides feeling cold, two very common signs of mild hypothermia are feeling tired and hungry.
Food is a key aspect of treating mild hypothermia. Simple sugars and carbohydrates such as hot, sugary beverages (Jell-O and hot cocoa) are a good start, followed by proteins and sugars like candy bars with nuts, a sandwich, and trail mix. Finally, carbohydrates and fats (such as peanut butter, cheese, and pasta) keep the body fueled with lasting energy.
If treated properly, your patient should fully recover within a few hours or less. If they don’t recover as hoped, be prepared to treat them for severe hypothermia.
Severe hypothermia is defined as a core temperature of 92°F. At this point, shivering may be so severe that they may be unable to walk or speak. If the core reaches 88°F, shivering stops (as does speaking), and they will most likely be found in the fetal position. If the core temperature reaches less than 86°F, the body may revert to a metabolic state (hibernation) where vital signs will be extremely low, but still be alive.
Ending exposure to the cold and replacing wet clothing with dry, warm clothing is crucial! Passively rewarm the core first. If patient is alert enough to speak and swallow, giving something warm to drink will do wonders. Boil a cup or two of water and mix in a packet of Jell-O. The higher sugar content and warmth will go straight to their core and will warm them up faster than watered-down hot chocolate. If the patient is severely hypothermic, wrap them in a hypothermia wrap (also called a “human burrito”).
Be sure to place water bottles filled with boiling hot water in socks to avoid burning the patient. As an important side note, sleeping bags don’t create heat; they only trap in what heat already exists. This is why we put the warm Nalgene bottles in the sleeping bag with the patient; the sleeping bag and blankets trap that heat and slowly warm up the air around the patient.
DO NOT USE BODY-TO-BODY CONTACT TO WARM A HYPOTHERMIC PATIENT (no sharing a sleeping bag)!
Source: Wilderness First Aid - A Pocket Field Guide (ISBN 9781304726773)