Mp. Meyer et al., A clinical comparison of radiant warmer and incubator care for preterm infants from birth to 1800 grams, PEDIATRICS, 108(2), 2001, pp. 395-401
Objective. The objective of this study was to compare radiant warmer and in
cubator care for preterm infants from birth with respect to temperature con
trol and weight gain.
Methods. Sixty preterm infants <33 weeks' gestation were randomized at birt
h to radiant warmer or incubator care. The initial goal was to maintain abd
ominal temperature at 36.8<degrees>C in both groups and axillary temperatur
e at 36.8 to 37.3 degreesC; air servocontrol was used for incubator infants
. Infants in both groups received added humidity for 5 days if their weight
was <1000 g and for 3 days if they weighed between 1000 and 1249 g. During
a 3-hour period on days 1 to 7, recordings of abdominal, forehead, and foo
t temperatures were obtained. The percentage of the recording time during w
hich the abdominal temperature was in the target range of between 36<degree
s>C and 37.5 degreesC was determined as an indicator of temperature control
. Weight gain from birth to 1800 g was compared. Secondary outcomes include
d fluid balance and clinical events.
Results. There were 30 infants in each group; 48 were <1500 g (of whom 17 w
ere <1000 g). There were no significant differences in birth weight, gestat
ion, gender, or illness severity scores in the 2 groups. Significant differ
ences in temperature control were noted on day 1. Although admission temper
atures were similar, lower abdominal temperatures were noted in the first 2
hours of life in the incubator group (medians were 36.6 degreesC and 35.9
degreesC in the radiant warmer and incubator groups, respectively). Similar
ly, mean abdominal temperatures during the 3-hour recording on day 1 were l
ower in the incubator group, and infants in this group spent a significantl
y greater percentage of the recording time with temperatures outside the ta
rget range (17.3% compared with 0.88%). Other temperature recordings from t
he forehead and foot were not significantly different in the groups. Fluid
intakes were higher for infants under radiant warmer on days 2, 3, and 4, a
nd the difference amounted to a mean of 12.8 mL/kg/d. Maximum sodium levels
in the first week were similar in the 2 groups. Mean weight gain was 17.4
g/kg/d for the radiant warmer group and 17.1 g/kg/d for the incubator group
; days to regain birth weight and length of hospital stay were not signific
antly different. Greater numbers of infants in the radiant warmer group req
uired phototherapy, and adverse events (which included death, necrotizing e
nterocolitis, chronic lung disease, grade 3 or 4 intraventricular hemorrhag
e, periventricular leukomalacia, or retinopathy requiring laser treatment)
were less frequent in the radiant warmer group (1 infant compared with 8 in
the incubator group; relative risk 0.1; 95% confidence intervals: 0.01-0.8
2).
Conclusions. This study has shown differences in abdominal temperatures on
day 1 and outcome, although the latter finding should be viewed with cautio
n because of the sample size. The results indicate benefits for the initial
use of the radiant warmer after birth. Although fluid requirements were hi
gher in the radiant warmer group for days 2 through 4, the increased fluid
volumes were given without apparent adverse effect.