Total Body Polyethylene Wraps for Preventing Hypothermia in Preterm Infants: A Randomized Trial Nicoletta Doglioni, MD1, Francesco Cavallin, MS2, Veronica Mardegan, MD1, Silvia Palatron, MD3, Marco Filippone, MD3, Luca Vecchiato, MD4, Massimo Bellettato, MD4, Lino Chiandetti, MD1, and Daniele Trevisanuto, MD1 Objective To evaluate whether a polyethylene total body wrapping (covering both the body and head) is more effective than conventional treatment (covering up to the shoulders) in reducing perinatal thermal losses in very preterm infants. Study design This was a multicenter, prospective, randomized, parallel 1:1, unblinded, controlled trial of infants 38 C. Conclusion Total body wrapping is comparable with covering the body up to the shoulders in preventing postnatal thermal losses in very preterm infants. (J Pediatr 2014;-:---).
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n both developed and developing countries, hypothermia is an important risk factor for morbidity and mortality in newborns.1-5 The conventional approach of drying the baby with a prewarmed towel and radiant warmers is unsuccessful in a large proportion of very preterm infants.6-9 Additional approaches aimed at preventing heat loss in very preterm infants in the delivery room (DR) include an elevated DR temperature,10 occlusive polyethylene wrapping,7-9 polyethylene cap,11 exothermic mattress,12,13 and warmed humidified resuscitation gases.14 Early skin-to-skin contact is another technique for reducing heat losses,15 but its role remains to be confirmed.4,16 To date, no single approach has been entirely successful at maintaining normothermia in very preterm infants in the DR.4 A combination of interventions could help achieve this goal.4,16,17 Use of a polyethylene occlusive skin wrap covering the body up to the shoulders to reduce postnatal heat loss in very preterm infants7-9,16 represents the standard of care recommended by the International Guidelines for Neonatal Resuscitation18 and by the European consensus guidelines on the management of neonatal respiratory distress syndrome in preterm infants.19 A polyethylene head cap also reduces heat loss with comparable efficacy to that obtained with the wrap.11 However, the proportion of infants with hypothermia (temperature 0.5 C between the total body and control groups, with an SD of 1, a power of 0.80, and a type I error of 0.05, the sample size was estimated in 50 subjects for each group. We chose the effect size of 0.5 C because we considered this improvement clinically relevant. Eligible infants were assigned to the total body wrap or control group at 1:1 for each participating center according to a computer-generated, randomized sequence. The randomized allocation was concealed in double-enclosed, opaque, sealed, and sequentially numbered envelopes prepared at University Hospital of Padua and then distributed to participating centers. Based on historical admission data, 70 envelopes were assigned to Padua, 20 envelopes were assigned to Vicenza, and 10 envelopes were assigned to Camposampiero. In the DR or operating room, the next sequential randomization envelope was opened only when the infant was deemed eligible by the attending neonatologist. The assigned Doglioni et al
- 2014
ORIGINAL ARTICLES
procedure (total body wrap or up to shoulders wrap) was then performed. Infants of multiple births were randomized as individuals. Neither caregivers nor outcome assessors were masked to treatment allocation. Statistical Analyses Categorical data are expressed as number and percentage; continuous data, as mean SD or median (IQR). Categorical data were compared using the Fisher test; continuous data used the Student t test or Mann-Whitney U test. Correlations between continuous data were evaluated using the Pearson or Spearman correlation coefficient. A stepwise regression model was estimated to identify the independent effect of the two wrapping strategies on temperature, adjusting for possible confounders. All variables associated with temperature on NICU admission (P < .05 or
I
n both developed and developing countries, hypothermia is an important risk factor for morbidity and mortality in newborns.1-5 The conventional approach of drying the baby with a prewarmed towel and radiant warmers is unsuccessful in a large proportion of very preterm infants.6-9 Additional approaches aimed at preventing heat loss in very preterm infants in the delivery room (DR) include an elevated DR temperature,10 occlusive polyethylene wrapping,7-9 polyethylene cap,11 exothermic mattress,12,13 and warmed humidified resuscitation gases.14 Early skin-to-skin contact is another technique for reducing heat losses,15 but its role remains to be confirmed.4,16 To date, no single approach has been entirely successful at maintaining normothermia in very preterm infants in the DR.4 A combination of interventions could help achieve this goal.4,16,17 Use of a polyethylene occlusive skin wrap covering the body up to the shoulders to reduce postnatal heat loss in very preterm infants7-9,16 represents the standard of care recommended by the International Guidelines for Neonatal Resuscitation18 and by the European consensus guidelines on the management of neonatal respiratory distress syndrome in preterm infants.19 A polyethylene head cap also reduces heat loss with comparable efficacy to that obtained with the wrap.11 However, the proportion of infants with hypothermia (temperature 0.5 C between the total body and control groups, with an SD of 1, a power of 0.80, and a type I error of 0.05, the sample size was estimated in 50 subjects for each group. We chose the effect size of 0.5 C because we considered this improvement clinically relevant. Eligible infants were assigned to the total body wrap or control group at 1:1 for each participating center according to a computer-generated, randomized sequence. The randomized allocation was concealed in double-enclosed, opaque, sealed, and sequentially numbered envelopes prepared at University Hospital of Padua and then distributed to participating centers. Based on historical admission data, 70 envelopes were assigned to Padua, 20 envelopes were assigned to Vicenza, and 10 envelopes were assigned to Camposampiero. In the DR or operating room, the next sequential randomization envelope was opened only when the infant was deemed eligible by the attending neonatologist. The assigned Doglioni et al
- 2014
ORIGINAL ARTICLES
procedure (total body wrap or up to shoulders wrap) was then performed. Infants of multiple births were randomized as individuals. Neither caregivers nor outcome assessors were masked to treatment allocation. Statistical Analyses Categorical data are expressed as number and percentage; continuous data, as mean SD or median (IQR). Categorical data were compared using the Fisher test; continuous data used the Student t test or Mann-Whitney U test. Correlations between continuous data were evaluated using the Pearson or Spearman correlation coefficient. A stepwise regression model was estimated to identify the independent effect of the two wrapping strategies on temperature, adjusting for possible confounders. All variables associated with temperature on NICU admission (P < .05 or
