Respiratory
Stressors

Premature babies have extreme central nervous system vulnerability and may be susceptible to the long-lasting changes in physical structure and operation of the brain associated with premature birth.([FOOTNOTE=Salmaso N, Jablonska B, Scafidi J, Vaccarino FM, Gallo V. Neurobiology of premature brain injury. Nat Neurosci. 2014;17(3):341-346.],[ANCHOR=],[LINK=])^,([FOOTNOTE=Newnham CA, Inder TE, Milgrom J. Measuring preterm cumulative stressors within the NICU: the Neonatal Infant Stressor Scale. Early Hum Dev. 2009;85(9):549-555.],[ANCHOR=],[LINK=]) The most common types of brain injury seen in premature infants are diffuse injury to the white matter as well as gray matter and hippocampal abnormalities.³

Beyond prematurity itself, low blood oxygen levels resulting from immature lung development,³ nutritional stress,([FOOTNOTE=Kuenen K, van Elburg RM, van Bel F, Benders MJNL. Impact of nutrition on brain development and its neuroprotective implications following preterm birth. Pediatr Res. 2015;77(1):148-155.],[ANCHOR=],[LINK=]) and environmental stresses([FOOTNOTE=Smith GC, Gutovich J, Smyser C, et al. Neonatal intensive care unit stress is associated with brain development in preterm infants. Ann Neurol. 2011;70(4):541-549.],[ANCHOR=],[LINK=]) have been linked to brain injury.

Alterations in brain structure due to prematurity may persist into adolescence and are associated with long-term cognitive difficulties, "particularly those involved with language and executive functions, and psychiatric illnesses including autistic spectrum and anxiety disorders."³

Retinopathy of prematurity (ROP) is an eye disease that primarily affects premature infants who weigh 1500 grams or less at birth.([FOOTNOTE=Jordan CO. Retinopathy of prematurity. Pediatr Clin N Am. 2014;61:567-577.],[ANCHOR=],[LINK=]) Approximately 14% of childhood blindness in the United States is associated with ROP, making it the third leading cause of blindness in American children.⁸

ROP is thought to be caused by growth of abnormal blood vessels in the retina which may bleed, which can cause retinal scarring and may eventually lead to retinal detachment.([FOOTNOTE=Facts About Retinopathy of Prematurity (ROP). National Eye Institute Web site. https://www.nei.nih.gov/health/rop/rop. Accessed December 3, 2014.],[ANCHOR=],[LINK=])

Major risk factors for ROP include high blood levels of oxygen (due to treatment with excessive supplemental oxygen) and low birth weight.⁸ Oxygen saturation between 90% and 95% appears to be the safest target to reduce the risk of ROP in premature infants.⁸