Which infant would have the greatest risk for evaporative heat loss?

Which infant would have the greatest risk for evaporative heat loss?

• A. 40 weeks gestation
• B. 34 weeks gestation
• C. 30 weeks gestation
• D. 28 weeks gestation

Answer: (C)

Evaporative heat loss hinges on how mature the infant’s skin barrier is. Water can evaporate from the skin easily when the barrier is immature, and preterm babies lose more heat this way because their skin is thinner, more permeable, and they have a higher surface area-to-body weight ratio. They often have little insulating fat and less vernix, which normally helps retain moisture and protect the skin. Because skin maturity advances with gestational age, the youngest preterm infant has the greatest risk for evaporative heat loss. Among the options, the most premature infant would be at the highest risk, since the earlier the gestational age, the more immature the skin barrier and the greater the potential for water loss. In practice, that means the infant around 28 weeks would have the greatest evaporative heat loss risk, followed by the 30-week infant, then the more mature preterms, and finally term infants. To reduce this risk, keep the infant dry, use humidity or a humidified environment, minimize exposure to dry air, and use occlusive coverings or radiant warmth as appropriate.

Evaporative heat loss hinges on how mature the infant’s skin barrier is. Water can evaporate from the skin easily when the barrier is immature, and preterm babies lose more heat this way because their skin is thinner, more permeable, and they have a higher surface area-to-body weight ratio. They often have little insulating fat and less vernix, which normally helps retain moisture and protect the skin. Because skin maturity advances with gestational age, the youngest preterm infant has the greatest risk for evaporative heat loss.

Among the options, the most premature infant would be at the highest risk, since the earlier the gestational age, the more immature the skin barrier and the greater the potential for water loss. In practice, that means the infant around 28 weeks would have the greatest evaporative heat loss risk, followed by the 30-week infant, then the more mature preterms, and finally term infants. To reduce this risk, keep the infant dry, use humidity or a humidified environment, minimize exposure to dry air, and use occlusive coverings or radiant warmth as appropriate.