RESPIRATORY WATER LOSS IN RELATION TO GESTATIONAL AGE IN NEWBORN INFANTS

Abstract

We have earlier shown that the transepidermal water loss is much higher in the preterm infant than in the fullterm infant. Recently we found that the respiratory water loss (RWL) contributes more than 50 % to the total insensible water loss at rest in fullterm infants on their first day after birth. We have now studied RWL, oxygen consumption and carbon dioxide production in preterm infants. The method used is based on an open flow-though system with a mass-spectrometer for gas analysies. Measurements were made in infants of gestational ages between 29 and 36 completed weeks with the infant at rest and at the first day after birth. The infants were studied in incubators with ambient humidity of 50 % and ambient temperature so that the body temperature was stable between 36.5 and 37 °C. The results showed no clear difference in RWL in relation to gestational age. In addition there was no clear difference in oxygen consumption in relation to gestational age. This means that the RWL contributes to a much lesser extent to the total insensible water loss in the preterm infant than in the fullterm infant.