17 - Temperature Regulation

Abstract

The provision of an appropriate and stable thermal environment is a central component of the care of the newborn infant whether in the delivery room or during subsequent care of an unstable or premature infant. Temperature instability in the newborn is associated with an increase in metabolic demands including increased oxygen consumption, and it may contribute to the severity of ongoing illness or to increased mortality in low birth weight infants. Choosing the optimal environmental temperature requires an understanding of the causes of heat loss under various conditions as well as the requisite measures to prevent body cooling and maintain normal homeostasis. The four main causes of heat loss are radiation, convection, evaporation, and conduction in order of magnitude and will vary with changes in environmental temperature. For example, the risk for evaporative loss is highest at birth due to the relatively large surface area of exposed wet skin. Radiant heat loss is subsequently the dominant cause of cooling. Protective thermal management has been a major factor in improving survival and outcomes in premature and sick infants, and it requires an ongoing assessment of needs and effectiveness of various interventions including clothing, caps, covers, type of incubator, radiant warmer, heated mattress, plastic body wraps, heat shields, room temperature, humidity, and changing fluid requirements and losses related to temperature changes. These considerations should apply to various clinical settings including delivery rooms, infant transport, full-term nurseries, stabilization rooms, rooming-in with the mother, and skin-to-skin care in the NICU.