title: Very preterm infants can detect small variations in light levels in incubators.
abstract: OBJECTIVE
  This prospective observational study was designed to improve our understanding of the responses of very preterm infants to light level variations in incubators and to evaluate what determined those reactions.
  
  
  METHODS
  The physiological responses of 27 very preterm infants were analysed following variations in the light level environments of their incubators over 10 hours. Heart and respiratory rates, systemic oxygen saturation and regional cerebral oxygen saturations were recorded using near-infrared spectroscopy, and the variation of each parameter was analysed.
  
  
  RESULTS
  We analysed 332 light level changes. Heart rate increased by 3.8 beats per minute (range -2.6 to 12.6), respiratory rate by six cycles per minute (-1.5 to 26) and regional cerebral oxygen saturation by 1.1% (-0.5% to 3.9%) (p < 0.05 each) when delta lux was over 50. Only respiratory rate decreased significantly, by -8.4 cycles per minute (-28 to -0.4), when delta lux was 50 or lower (p < 0.05). The initial level of illumination altered the very preterm infants' responses, with higher reactivity for higher ambient light levels.
  
  
  CONCLUSIONS
  Very preterm infants reacted to moderate variations in illumination in their incubator, within recommended ranges of light levels, suggesting that they may detect even small light level variations.
authors.affiliation: Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364 CNRS/Université de Strasbourg, Strasbourg, France.|Médecine et Réanimation du nouveau-né, Service de Pédiatrie 2, Pôle Médico-Chirurgical Pédiatrique, Hôpital de Hautepierre, Centre Hospitalier Universitaire de Strasbourg, Strasbourg, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Zores
authors.affiliation: Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364 CNRS/Université de Strasbourg, Strasbourg, France.
authors.forename: André
authors.initials: A
authors.lastname: Dufour
authors.affiliation: Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364 CNRS/Université de Strasbourg, Strasbourg, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Pebayle
authors.affiliation: Médecine et Réanimation du nouveau-né, Service de Pédiatrie 2, Pôle Médico-Chirurgical Pédiatrique, Hôpital de Hautepierre, Centre Hospitalier Universitaire de Strasbourg, Strasbourg, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Langlet
authors.affiliation: Médecine et Réanimation du nouveau-né, Service de Pédiatrie 2, Pôle Médico-Chirurgical Pédiatrique, Hôpital de Hautepierre, Centre Hospitalier Universitaire de Strasbourg, Strasbourg, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Astruc
authors.affiliation: Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364 CNRS/Université de Strasbourg, Strasbourg, France.|Médecine et Réanimation du nouveau-né, Service de Pédiatrie 2, Pôle Médico-Chirurgical Pédiatrique, Hôpital de Hautepierre, Centre Hospitalier Universitaire de Strasbourg, Strasbourg, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Kuhn
mesh_terms: D005260:Female; D006801:Humans; D007186:Incubators, Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology / Q000523:psychology*; D008027:Light; D008297:Male; D011446:Prospective Studies; D014796:Visual Perception
keywords: Light levels; Light protection; Physiological response; Preterm infant; Visual sensitivity