Weigh 401-1000 g at birth.
Extremely preterm infants less than 28 weeks gestational age born in the 1990s, 25% had a disability at preschool age, such as impaired mental development, cerebral palsy, blindness, or deafness.
Almost all extremely preterm infants of less than 28 weeks gestation experience intermittent hypoxemia and bradycardia during their stay in neonatal intensive units.
Many episodes of hypoxemia and bradycardia in extremely preterm infants are due to apnea of prematurity, but a significant number of such episodes occur in mechanically ventilated infants because of cardiorespiratory instability.
Infants born before 25 weeks gestation have impairment rates of greater than 50%.
Up to 50% of infants with extremely low birthweight have some degree of neurodevelopmental impairment.
Account for less than 1% of all births but one third of total infant mortality.
Approximately 25% of extremely preterm babies die and 20% survive with substantial neurologic or cognitive deficits.
Extremely preterm infants are at risk for neurodevelopmental impairments due to potential events, such as intraventricular hemorrhage or periventricular leukomalacia, sepsis, necrotizing enterocolitis, bronchopulmonary, dysplasia, and poor growth.
As many as 15% of these infants develop cerebral palsy and half develop impaired cognition and behavioral deficits.
Infections are frequent among such preterm infants and are associated with neurodevelopmental and growth impairments.
Anemia may be associated with impaired oxygen supply to the brain and prematurity related brain injury in combination with apnea and intermittent hypoxemia with circulatory insufficiency during a period of rapid brain growth and development.
Red blood cell transfusion in such premature infants can have complications such as intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, retinopathy of prematurity and death.
Infants born extremely prematurely usually require respiratory support.
High-frequency oscillatory ventilation (HFOV) is a means to reduce the risk of bronchopulmonary dysplasia among neonates receiving ventilatory support.
HFOV uses a constant pressure applied to improve lung volume and oxygenation, while ventilation is achieved with the use of very low tidal volumes.
Initial randomized trials comparing HFOV with conventional ventilation showed a higher incidence of grade 3 or 4 intraventricular hemorrhage and periventricular leukomalacia.
Subsequent studies did not confirm these results: randomized trials subsequently resulted in significant but modest reductions in the risk of bronchopulmonary dysplasia, but overall did not show any advantage with respect to short-term outcomes including bronchopulmonary dysplasia.
Are monitored with pulse oximetry for several weeks after birth because of need for supplemental oxygen either intermittently or continuously.
Targeting oxygen saturations of 85% to 89% compared with 91% to 95% has no effects on rate of death or disability at 18 months(Schmidt B et al).
School-aged outcomes for these children are associated with very high rates of chronic health conditions and developmental problems compared with normal birth weight controls.
Associated with higher rates of chronic conditions, functional limitations and special health care needs compared with normal birth weight controls (Hack M et al).
The Extremely Preterm Infants Study in Sweden (EXPRESS) Associated with a infant survival rate of 70%, attributed to active perinatal care.
In the above study at 2 1/2 years 73% of children born with extreme prematurity had little or no disability, and neurodevelopmental outcomes improved with each week of gestational age (Serenius F et al).
In extremely preterm infants, treatment, guided by cerebral oximetry monitoring for the first 72 hours after birth is not associated with a lower incidence of death or severe brain injury at 36 weeks’ postmenstrual age than usual care.
Maternal milk intake has been associated with decreased risk of sepsis, bronco pulmonary dysplasia and necrotizing enterocolitis, but does not decrease adverse neurodevelopmental outcomes.