ABSTRACT
This chapter provides an overview of physiology and mechanisms of neonatal thermoregulation, heat loss and heat gain, and the management strategies required to ensure sound thermal control. Temperature is regulated by balancing heat production against heat loss, a balance that is continually being disturbed by changes in metabolic rate or external factors. The newborn infant has limited capabilities to produce heat by shivering, and when a baby is born prematurely, poor muscular development means the neonate has no means of changing position to preserve heat. The majority of brown fat is located around the neck, between the scapulae, across the clavicular line and around the sternum. It also surrounds the major thoracic vessels and kidneys. Brown fat cells contain a nucleus, glycogen and mitochondria. Insulin acts in the liver and muscles to increase glycogen synthesis, and in the adipose cells it increases glucose uptake.
