Intensive care for extreme prematurity - Moving beyond gestational age

Center for Clinical Research and Evidence-Based Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA.
New England Journal of Medicine (Impact Factor: 54.42). 05/2008; 358(16):1672-81. DOI: 10.1056/NEJMoa073059
Source: PubMed

ABSTRACT Decisions regarding whether to administer intensive care to extremely premature infants are often based on gestational age alone. However, other factors also affect the prognosis for these patients.
We prospectively studied a cohort of 4446 infants born at 22 to 25 weeks' gestation (determined on the basis of the best obstetrical estimate) in the Neonatal Research Network of the National Institute of Child Health and Human Development to relate risk factors assessable at or before birth to the likelihood of survival, survival without profound neurodevelopmental impairment, and survival without neurodevelopmental impairment at a corrected age of 18 to 22 months.
Among study infants, 3702 (83%) received intensive care in the form of mechanical ventilation. Among the 4192 study infants (94%) for whom outcomes were determined at 18 to 22 months, 49% died, 61% died or had profound impairment, and 73% died or had impairment. In multivariable analyses of infants who received intensive care, exposure to antenatal corticosteroids, female sex, singleton birth, and higher birth weight (per each 100-g increment) were each associated with reductions in the risk of death and the risk of death or profound or any neurodevelopmental impairment; these reductions were similar to those associated with a 1-week increase in gestational age. At the same estimated likelihood of a favorable outcome, girls were less likely than boys to receive intensive care. The outcomes for infants who underwent ventilation were better predicted with the use of the above factors than with use of gestational age alone.
The likelihood of a favorable outcome with intensive care can be better estimated by consideration of four factors in addition to gestational age: sex, exposure or nonexposure to antenatal corticosteroids, whether single or multiple birth, and birth weight. ( numbers, NCT00063063 [] and NCT00009633 [].).

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Available from: Charles E Green, Aug 18, 2015
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    Twin Research and Human Genetics 08/2012; 15(4):532-6. DOI:10.1017/thg.2012.33 · 1.92 Impact Factor
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    • "The current recommended single course of synthetic corticosteroids is associated with substantial improvement in acute neonatal morbidity and mortality after premature birth (Roberts & Dalziel, 2006), with similar benefits from available agents (Brownfoot et al. 2008). There is some evidence for reduced risk of intraventricular haemorrhage (Brownfoot et al. 2008) and neurodevelopment impairment (Tyson et al. 2008). Although it is possible that exposure to repeated courses may be associated with attention problems (Crowther et al. 2007) or greater risk of cerebral palsy (Wapner et al. 2007), very long-term follow-up suggests normal cognitive outcomes in patients treated with single courses (Dalziel et al. 2007). "
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    • "Second, we have no information on the antenatal administration of corticosteroids. The neonatal mortality rate of singletons and twins born after 23 to 29 weeks' gestation is lowered by the administration of steroids (Tyson et al., 2008; Garite et al., 2004). Third, we used birth order and not order of presentation . "
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