Transepidermal water loss and skin hydration in preterm infants during phototherapy.

TEWL and skin hydration was measured in 7 body areas before and during phototherapy in 31 preterm infants (gestational age 25 to 36 weeks). Each patient served as his/her own control. There was a mean increase of 26.4% in TEWL during phototherapy. Most prominent increases were recorded in the cubital fossa (45.9%), groin (36.4%), and back (29%). There were no significant differences in stratum corneum moisture in six of the seven body areas before and during phototherapy. This study provides a better understanding of skin physiology during phototherapy in preterm infants and has important implications for the estimation of fluid replacement.