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CHAPTER 34 .
The Preterm Newborn
RESPIRATORY DISTRESS SYNDROME. .. .. ... 636
NECROTIZING ENTEROCOLITIS . .... ... 638
RETINOPATHY OF PREMATURITY ..639
BRAIN DISORDERS .. ........ . 639
INTRACRANIAL .......... 639
CEREBRAL PALSY . .... ............. 640 !he prognosis or the child depends, of course, upon the degree of development, as wel as the pathological condition or which premature delivery is undertaken. Generaly speaking, in the case of children born bore the thiry-second week, the chances of surviving are vey small.
-]. Whitridge Williams (1903)
At the time of this textbook's irst edition, preterm delivery of a living newborn was frequently followed by neonatal death. Contrast this with today's technological advances that have advanced the threshold of viability to 22 to 24 weeks' gestation. Even so, the preterm newborn is susceptible to various serious medical complications both early and later in life (Table 34-1). A less commonly cited cause of morbidity and mortality is congenital malformations, which are much more prevalent in preterm births.
These complications of prematurity can be placed in perspective in terms of overall neonatal outcomes. In 2009, two thirds of all infant deaths in the United States were in the 12 percent born before 37 weeks (Mathews, 2013). Fortunately, during the past decade, rates of preterm birth have declined from approximately 12 percent in 2007 to 10 percent in 2014. This is in part due to a decline in births to teen mothers (Ferre, 2016).
The seminal complication of the preterm newborn is respiratory distress syndrome (DS). This results from immature lungs that are unable to sustain necessary oxygenation. Resulting hypoxia is an underlying associated cause of neurological damage such as cerebral palsy. In addition, hyperoxia, a side efect of DS treatmentacontributes to morbidities such as bronchopulmonary dysplasia, pulmonary hypertension, necrotizing enterocolitis, periventricular leukomalacia, and retinopathy of prematurity.
To provide blood gas exchange immediately following delivery, the lungs must rapidly fill with air while being cleared of fluid. Concurrently, pulmonary arterial blood low must rise remarkably. Although some of the luid is expressed as the chest is compressed during vaginal delivery, most is absorbed through the
TABLE 34-1. Complications of Prematurity
Retinopathy of prematurity (ROP)