The thermoneutral zone (TNZ) defines the environmental temperature range that allows a neonate to maintain normal body temperature with minimal metabolic and oxygen requirements.
Definition
•
The TNZ is a narrow environmental temperature range in which normal body temperature is maintained with the least basal metabolic rate and oxygen utilization.
Factors affecting the required temperature
•
The TNZ varies with gestational age and postnatal age.
•
The required environmental temperature range is higher at lower gestation, in naked rather than clothed neonates, and at early rather than later postnatal ages.