ABSTRACT
Vital Signs and Resuscitation, by Joseph V. Stewart. ©2003 Landes Bioscience.
mother. Infants, particularly newborns, are prone to hypothermia. The high ratio of body surface area to body mass causes 4 times more heat loss by radiation and evaporation than in the adult. A contributing factor is the sparse insulation against heat loss from the developing keratinization of skin and subcutaneous fascia. Babies do not shiver. Instead they respond by secreting catecholamines which constrict vessels and mobilize brown fat. The mobilization of brown fat, which contains mitochondria that hydrolyze and oxidize free fatty acids for energy, increases the metabolic rate by two fold or more. Impaired tissue perfusion from the cold may result in metabolic acidosis, shock and cardiac arrest. The incubator or overhead heater main tains the infant at a temperature of 97.7-98.6 F°(36.5-37°C).
