Hypothermia is characterized in a drop of body to less than 35ºC. It occurs when the body loses more heat than it can generate, and is normally caused by prolonged exposure to cold environments.

A decrease in temperature occurs in three stages:

Body temperature drops by 1 or 2 ºC, causing chills and slight numbness in the hands or feet
Body temperature drops by 2 to 4 ºC, which causes the extremities to start turning blue
Body temperature drops even further, which can lead to a loss of senses and difficulty breathing.

If you notice the early signs of hypothermia, it is important to increase your body temperature with warm clothing and by moving to a warm place. Prolonged exposure to low temperatures can cause serious effects on the body.

Common symptoms

The main symptoms of hypothermia vary depending on its severity. The most common ones are:

Mild hypothermia (33 to 35ºC)	Moderate hypothermia (30 to 33ºC)	Severe hypothermia (less than 30ºC)
Tremors	Violent, uncontrollable tremors	Loss of control of arms and legs
Cold feet and hands	Slow, shaky speech	Loss of senses
Numbness in the arms and legs	Slower and weaker breathing	Shallow breathing, which may even stop
Loss of dexterity	Weak pulse	Irregular or no pulse
Fatigue	Difficulty controlling body movements	Dilated pupils

Moderate hypothermia can also lead to a lack of attention, memory loss or drowsiness, which may progress to amnesia as the condition worsens.

In babies, the signs of hypothermia are cold skin, a reduced reaction, lethargy and refusal to eat. If you notice symptoms of hypothermia in a child, seek medical attention immediately.

Main causes

The most common cause of hypothermia is prolonged exposure to cold weather, environment or water.

Other situations that can cause hypothermia include:

Malnutrition
Heart diseases
Low thyroid activity
Excessive alcohol intake

Furthermore, there are some risk groups that are more prone to to drops in body temperature, like children, older adults, those who abuse alcohol or drugs, and those with mental disabilities that prevent the correct assessment of bodily needs.

Although most cases of hypothermia can be reversed without causing serious damage to the body, body temperature can continue to drop if treatment is not initiated, which can be life-threatening.

Treatment options

Treatment for hypothermia should be initiated as quickly as possible to prevent problems like a such as stroke, heart attack or even organ failure and death.

It is important to call an ambulance and to warm the victim slowly, either by placing them in a warmer environment, removing wet or cold clothing, or placing blankets and hot water bottles over them.

In the more serious cases, treatment must be carried out in a hospital setting with more specific techniques such as dialysis that involves heating the blood and heated IV solutions.

How to prevent

The best way to prevent hypothermia is to dress appropriately for cold weather and to avoid prolonged exposure to cold environments or water. If you are wearing wet clothes, you should remove them to keep your skin as dry as possible. This care is especially applicable to babies and young children, who are at greater risk of losing heat and are less likely to report cold sensations.