Methods of Heat Loss in Newborns
January 18, 2011 · Leave a Comment
The maintenance of body temperature at birth or thermoregulation is assumed by infants. Neonates must produce and maintain enough heat to prevent cold stress. Cold stress can have serious and even fatal effects to the neonates.
Why are newborns more prone to losing heat?
Several features predispose a newborn to lose heat. The following characteristics are:
- The neonate’s skin is thin.
- The newborn’s blood vessels are close to the surface.
- Little subcutaneous or white fat is present to serve as a barrier for heat loss. (the percentage of subcutaneous fat in newborns is only half in adults)
- Newborns have three times more surface area to body mass than adults.
Methods of Heat Loss
When wet surfaces are exposed to the air evaporation occurs. Heat is lost when the surface dries. At birth the neonate is bathed with amniotic fluid. As the amniotic fluid dries up on the infant’s skin (evaporation), the infant loses heat. The same occurs in bathing an infant.
Ways to prevent heat loss by evaporation:
- Drying the infant as quickly as possible after birth.
- Drying the infant immediately after bathing.
When a neonate comes in direct contact with an object cooler than their skin heat loss by conduction occurs. Heat loss by conduction occurs when an infant is placed on a cooler surface or touching them with a cool object or hands.
Ways to prevent heat loss by conduction:
- Warming the objects that will touch an infant.
- Placing an infant against the mother’s skin helps prevent conductive heat loss.
When heat is transferred to the air surrounding the infant heat loss by convection takes place. If an air conditioner is kept on or when people move around near the infant increase loss of heat occurs.
Ways to prevent heat loss by convection:
- Keeping the newborn out of drafts.
- Maintaining warm environmental temperature.
- Keeping a preterm neonate in an incubator.
The transfer of heat to cooler objects that are not in direct contact with the neonate is called the heat loss by radiation. When infants are placed near cold windows or walls heat is lost by radiation. Even neonates placed in incubators losses heat to the walls of the incubator if it is cold even if the surrounding air temperature is warm.
Ways to prevent heat loss by radiation:
- Incubators must have double walls.
- Cribs and incubators should be placed away from the walls and windows.