Maintaining temperature is very important. When an infant’s skin becomes cold, the skin sends messages to the brain and in turn the brain sends out norepinephrine. Norepinephrine causes peripheral vasoconstriction and the blood is shunted to the core of the body. The vasoconstriction of the peripheral circulation also causes vasoconstriction results of the pulmonary system. Now, the blood can’t get to the lungs to pick up the needed oxygen in the lungs and therefore, shunts through the Foremen Ovale. Now, the blood is hypoxemic and when the blood arrives to the tissues, the tissues become hypoxic. Therefore, the body must resort to anaerobic metabolism and lactic acid is produced. When lactic acid is used instead of oxygen the pH drops and the infant becomes acidotic.
When the baby gets cold he uses up more glycogen to keep warm. Then he must utilize his glucose stores to keep warm, then the blood sugar drops and they become hypothermic along with hypoglycemic. Make sense?