Twenty-four insensible water loss (IWL) studies, measured as insensible weight loss (IL), were performed on 24 normal, term, newborn infants during the first two days of life. The IWL of infants placed under a radiant warmer (infrared radiant energy source) was significantly greater than the IWL of infants placed in a standard convection-type incubator (1.08±0.12 vs 0.53±0.05 gm/kg/hr; M±SE; P<.001).
The higher IWL of infants in the radiant warmer is probably on the basis of a higher skin-ambient temperature gradient or a higher skin-ambient vapor pressure gradient, or both. These data illustrate the importance of providing proportionally larger fluid intake for maintenance in infants under the radiant warmer environment for thermal control.
Williams PR, Oh W. Effects of Radiant Warmer on Insensible Water Loss in Newborn Infants. Am J Dis Child. 1974;128(4):511-514. doi:10.1001/archpedi.1974.02110290081014