The thermophysiology of the newborn infant

The preterm newborn, although a homeotherm in the true sense of the word, has increased heat and water losses when compared to the adult and these large losses necessitate providing a thermal environment which can allow a minimal resting metabolic rate. The physician who cares for newborn infants must direct special attention to the maintenance of "normal" body temperature of the low-birth-weight infant, whose survival may depend on such careful management. However, the physiology of temperature control is important for almost every aspect of the management of these infants; the immediate adaptation to extrauterine life, requirements for oxygen and calories, growth and development, and the diagnosis of infection. An understanding of these interrelated areas is highly relevant to the successful management of a wide variety of clinical problems in the newborn period.