Hypothermia usually refers to a person’s body temperature below 36 degrees, which may be a normal physiological response or may be caused by pathological factors such as hypothyroidism, immunocompromise, cardiogenic shock and other diseases. 1. Physiological response: when the temperature is too low, such as the body to keep warm and cold work is not done, such as clothing added in a timely manner, may lead to hypothermia. 2. Pathologic factors: (1) hypothyroidism: patients due to insufficient secretion of thyroid hormones, so that the patient’s energy metabolism rate decreases heat production, but also inhibit the thermoregulatory center caused by hypothermia performance, thus causing cold, fatigue, loss of appetite, pallor, face or limbs edema, as well as intestinal peristalsis, constipation and other symptoms. (2) Immunocompromise: some patients suffer from malnutrition and reduced immunity due to excessive weight loss, and their low body fat rate cannot withstand the cold, which will lead to the manifestation of hypothermia, thus hypothermia may be a precursor of immunocompromise. (3) Cardiogenic shock: patients with heart disease or trauma, due to severe lack of tissue perfusion, blood circulation disorders resulting in a gradual decrease in patient temperature, pale and bloodless, therefore, hypothermia may be a precursor to cardiogenic shock, it is recommended to consult a doctor in time to rescue. Body temperature is lower than 36 degrees, if it is not physiologically caused, it is recommended that the patient to go to the hospital in time to check, clear the cause of the disease to give targeted treatment, so as to avoid adverse consequences.