Hypothermia in children is defined by a core body temperature below 35°C (95°F). It is considered a medical emergency and is usually accidental in children. From 0.2-1 death(s) per million children under the age of 14 can be attributed to hypothermia.

Children are at higher risk than adults for hypothermia as they are unlikely to recognize the symptoms of impending hypothermia and have limited ability to avoid or escape exposure. Furthermore, children have a greater surface area to body mass ratio, predisposing them to more rapid radiant heat loss and ensuring that they cannot as effectively raise their body temperatures through glycogen mobilization or shivering.

Hypothermia can be characterized as mild (35°C-32°C), moderate (32°C-28°C), or severe (below 28°C). Clinical manifestations of hypothermia vary according to severity.

In mild cases, presentation includes pallor, shivering, tachycardia, and tachypnea. Moderate cases can present with lethargy, hallucinations, paradoxical undressing, hypoventilation, and decreased shivering. Severe cases present with coma, hypotension, arrhythmias, apnea, and pseudo-rigor mortis. Laboratory derangements such as hyper- or hypoglycemia, thrombocytopenia, leukopenia, elevated creatine phosphokinase (CPK) secondary to rhabdomyolysis, and abnormal liver function tests may also be present in patients with moderate or severe hypothermia. Despite being at higher risk for severe hypothermia, children often have better neurologic outcomes in the setting of severe hypothermia compared to adults.

The key to management is timely diagnosis and initial support of the patient's airway, breathing, and circulation (ABC). Patients should be removed from the hypothermic environment, and rewarming should be initiated as soon as possible. Cardiopulmonary resuscitation should be started immediately in patients with cardiopulmonary arrest. Rewarming can take several hours with the goal body temperature of 32°C-35°C.