Use of plastic bags to prevent hypothermia at birth in preterm infants--do they work at lower gestations?

Abstract

Background: Hypothermia at birth is strongly associated with mortality and morbidity in preterm infants. Occlusive wrapping of preterm infants during resuscitation, including polythene bags have been shown to prevent hypothermia.

Objectives: To evaluate the effectiveness of the introduction of polythene bags at resuscitation of infants born below 30 weeks gestation in a large tertiary neonatal centre.

Methods: Retrospective audit of admission temperatures of all infants born below 30 weeks gestation for two years before and two years after the introduction of polythene bags. Hypothermia was defined as admission axillary temperature < 36 degrees C.

Results: A total of 334 eligible infants were born during the study period. Two hundred and fifty-three (75.8%) had admission temperatures recorded. The incidence of hypothermia fell from 25% to 16%(p = 0.098) for the whole group since the introduction of polythene bags. The main reduction in hypothermia was seen in infants born above 28 weeks gestation (19.4% vs. 3.9%, p = 0.017). There was no significant effect in infants born between 28 weeks and 30 weeks (29.3% vs. 24.8%, p = 0.58).

Conclusions: Polythene bags are effective in reducing the incidence of hypothermia at admission in infants born below 30 weeks gestation. The benefit in infants born below 28 weeks gestation was only marginal. This is in contrast to previously published studies. This may be related to the comparatively low incidence of hypothermia at the study centre even prior to introduction of polythene bags.