Eight very low-birth-weight premature infants (mean birth weight 1.11 ± 0.05 [SEM] kg, mean gestation 30 ± 1 weeks, and mean age 9 ± 2 days) were studied under servocontrolled radiant warmers with and without a loosely fitted, transparent, and flexible Saran plastic blanket. Metabolic rate was significantly less in all infants when covered by the blanket (oxygen consumption was 7.99 ± 1.13 mL/kg/min v 9.00 ± 1.10 mL/kg/min uncovered, P < .001). There were also significant reductions in insensible water loss (1.86 ± 0.18 v 1.25 ± 0.20 mL/kg/h, P < .01) and in heat demand from the radiant warmer (14.3 ± 1.3 v 9.9 ± 1.4 mW/cm2, P < .001) when infants were nursed under the blanket compared with the control condition, respectively. Covering the critically ill, very low-birth-weight infant nursed under a radiant heater with a thin, transparent layer of Saran is beneficial in reducing oxygen consumption, insensible water loss, and the need for exposure to high levels of radiant heat. Further investigation to confirm the benefits and possible complications of plastic blankets should be conducted before routine use can be recommended.
CONDUCTION, CONVECTION, AND RADIATION IN A CLOSED CAVITY WITH A LOCAL RADIANT HEATER
