Heat balance in premature infants: comparative effects of convectively heated incubator and radiant warmer, with without plastic heat shield.

Insensible water loss, oxygen consumption, and carbon dioxide production were measured in eight premature infants under four different conditions: in conventional single-walled incubator with and without plastic heat shield, and under radiant warmer with and without heat shield. IWL was greater under the radiant warmer (3.40 +/- 1.50 ml/kg/hour, mean +/- SD) than in the incubator (2.37 +/- 1.15 ml/kg/hour) when both were compared without heat shield. Addition of the heat shield reduced IWL in the incubator (2.13 +/- 0.76 ml/kg/hour) but not under the radiant warmer (3.37 +/- 0.94 ml/kg/hour). There were no significant differences in VO2 or respiratory quotient between any two of the four study conditions.