Cycled light in the intensive care unit for preterm and low birth weight infants

Neonatal Unit, Mayanei HaYeshua Medical Centre, Bnei Brak, Israel.
Cochrane database of systematic reviews (Online) (Impact Factor: 5.94). 01/2011; DOI: 10.1002/14651858.CD006982.pub2
Source: PubMed

ABSTRACT The pregnant woman is exposed to variable intensities of lighting and sound and, in general, lower levels at night. Some of the lighting and sound reaches the fetus in the womb and induces circadian rhythms. Circadian is a term used to describe biological processes that recur naturally on a 24-hour basis. After birth, preterm infants are cared for in an environment that has no planned light-dark cycles or any other circadian entraining signals. Infants are exposed to either continuous bright light, continuous near darkness or an unstructured combination of the two. Our primary objective was to determine the effectiveness of cycled light (approximately 12 hours of light on and 12 hours of light off) on growth in preterm infants at three and six months of corrected gestational age. To May 2013, 506 infants have been enrolled in trials assessing the effect of cycled light. One study reported improved growth at three months of age in infants exposed to cycled lighting compared with continuous bright light. One study found no difference in weight at four months of age. Only a few outcomes reached statistical significance, which is likely to be due to the small number of infants enrolled in the studies, but trends for most outcomes (weight gain, length of stay, incidence of retinopathy of prematurity, time spent crying) favoured cycled light compared with near darkness and cycled light compared with continuous bright light.

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