Baby has a high fever of 40°C with cold hands and feet: why, and what to do?

Generally speaking, a high fever refers to a high body temperature. A baby having cold hands and feet at 40°C may be caused by peripheral circulation regulation, a rapid rising phase of fever, infantile急疹 (roseola), acute tonsillitis, pneumonia, or other reasons. Treatment options, such as general care and medication, can be adopted under a doctor's guidance. If your baby displays the above symptoms, seek timely medical attention for professional diagnosis and treatment. Detailed explanations are as follows:

1. Peripheral Circulation Regulation

When a baby has a high fever, the body prioritizes blood supply to vital organs by constricting peripheral blood vessels to reduce heat loss, resulting in decreased circulation to extremities such as hands and feet, causing them to feel cold. During the initial phase of fever, monitor temperature changes, dress the baby appropriately for warmth without overwrapping, to avoid further elevation of body temperature.

2. Rapid Rising Phase of Body Temperature

During the phase of rapidly increasing body temperature, heat production exceeds heat dissipation, and blood is mainly concentrated in the central areas of the body, leaving extremities with insufficient circulation, thus causing cold hands and feet. Closely monitor your baby's condition. If a rising temperature trend is detected, physical cooling measures can be used, such as wiping the forehead and neck arteries with lukewarm water, to prevent a rapid temperature spike.

3. Infantile急疹 (Roseola)

Infantile急疹 is generally caused by infection with human herpesvirus type 6 or 7. The virus triggers an immune response, leading to high fever and affecting blood circulation, causing cold hands and feet. It is often accompanied by mild symptoms like runny nose and cough. Medications such as acetaminophen suspension drops, ganciclovir dispersible tablets, and ibuprofen suspension may be used under a doctor's guidance for treatment.

4. Acute Tonsillitis

Acute tonsillitis is mainly caused by bacterial infection of the tonsils, often by group B hemolytic streptococcus. Bacteria and their toxins trigger an inflammatory response, causing high fever and circulatory abnormalities, leading to the above symptoms. It may also be accompanied by symptoms such as sore throat and difficulty swallowing. It is recommended to use medications such as penicillin G sodium injection, ibuprofen granules, and pediatric Yankian granules under medical guidance to relieve symptoms.

5. Pneumonia

Pneumonia is mostly caused by infection of the lungs by pathogens such as bacteria, viruses, or mycoplasma. Inflammation in the lungs stimulates the body, causing high fever and circulatory changes, leading to cold hands and feet. Symptoms may also include frequent coughing and rapid breathing. Treatment may include medications such as ceftriaxone sodium injection, azithromycin dry suspension, and budesonide suspension for inhalation, as directed by a physician.

In daily life, attention should be paid to the baby's personal hygiene and frequent handwashing; adjust clothing promptly according to weather changes to avoid catching a chill; and ensure timely vaccination to enhance the baby's immunity.