Covering isolettes to diminish light exposure

The premature infant finds him/herself in a foreign environment for which (s)he is ill-prepared biologically and developmentally. Vanderbiltís NICU attempts to provide developmentally supportive measures to reduce the infantís stress and foster appropriate neurodevelopment.

Minimizing bright light and loud noise exposure reduces stress in sick patients of any age group. Therefore, isolette covers are placed over infantís incubators to darken the prematureís environment. Such measures also intuitively more closely simulate the womb.

Providing the premature infant with defined light/dark periods may improve the infantís sleep/wake cycles and weight gain after discharge home. However, in the few studies performed, preventing ambient light exposure continuously has not been shown to improve premature infantsí medical or neurodevelopmental outcomes. Of particular note, retinopathy of prematurity (ROP) is neither caused by nor exacerbated by light exposure.

Therefore, when providing intensive care means intensive observation, infantsí isolettes should not be covered. For example, extremely premature infants in Giraffe incubators during their first critical days of life or infants in the throes of NEC should be readily visible.

Infants receiving mechanical ventilation and/or with umbilical catheters in place should not have their isolettes covered.

Discussed at the Collaborative Pathways meeting 7/11/01 and revisited at Clinical Division Meeting 1/21/02.


Kennedy KA, et al. Reduced lighting does not improve medical outcomes in very low birth weight infants. Journal of Pediatrics 2001; 139: 527-31.

Ariagno RL, et al. Developmental care does not alter sleep and development of premature infants. Pediatrics 1997; 100: E9.

Mann NP, et al. Effect of night and day on preterm infants in a newborn nursery: randomised trial. BMJ 1986: 293: 1265-7.

Reynolds JD, et al. Lack of efficacy of light reduction in preventing retinopathy of prematurity. N Engl J Med 1998; 338: 1572-6.

Phelps DL, Watts JL. Early light reduction for preventing retinopathy of prematurity in very low birth weight infants. Cochrane Neonatal Database of Systematic Reviews.