Well-Child Care for Preterm Infants
Soina Kaur Dargan, MD, FAAP, and Lynne M. Smith, MD, FAAP
A 10-week-old girl was discharged from the neonatal intensive care unit 2 weeks previously, where she had resided since birth. She was the 780 g (27.5 oz) product of a 26-week gestation born via spontaneous vaginal delivery to a 32-year-old primigravida. The perinatal course was complicated by premature rupture of membranes and maternal amnionitis. Several aspects of the neonatal course were significant, including respiratory distress that required surfactant therapy and 2 weeks of endotracheal intubation; a grade 2 intraventricular hemorrhage diagnosed at 1 week after birth; hyperbilirubinemia, which was treated with phototherapy; several episodes of apnea, presumably associated with the preterm birth; and a history of poor oral intake with slow weight gain.
The parents have a few questions about her feeding schedule and discontinuing the apnea monitor, but they feel relatively comfortable caring for their daughter at home. She is feeding well (2 oz of 22 cal/oz post- discharge formula for preterm infants every 2–3 hours) and, according to the family, is becoming progressively more alert. She sleeps on her back in a crib.
The infant’s weight gain has averaged 25 g (0.9 oz) per day. The remainder of the physical examination is normal, with the exception of dolichocephaly and esotropia of the left eye.
1. What constitutes well-child care in preterm infants?
2. What are the nutritional requirements of preterm infants in the months after discharge from the hospital?
3. What information must be considered in the nutritional assessment and developmental screening of preterm infants?
4. What immunization schedule is appropriate for preterm infants? Do they require any special immunizations?
5. What specific conditions or illnesses are more likely to affect preterm infants than term infants?
Preterm birth is defined as birth before 37 completed weeks of gestation. However, the increased frequency of adverse neonatal outcomes in neonates born at 37 and 38 weeks’ gestation led the American College of Obstetricians and Gynecologists to redefine optimal delivery as 39 weeks’ gestation to eliminate nonmedically indicated deliveries prior to this time. Because advances in neonatal care have resulted in improved survival, an increased demand exists for skilled primary care physicians who can care for the preterm infant. Providing primary care for these infants is an important and challenging task and often requires coordination of medical, developmental, and social services for multiple chronic conditions. Because preterm infants are at increased risk for impaired growth and developmental delay, longer well-child visits may be necessary to evaluate their nutritional and developmental progress and assess how families have adjusted to caring for them at home. Primary care physicians must learn to manage these and many other complex issues while providing families with comprehensive anticipatory guidance. Providing a medical home in which care is accessible, comprehensive, continuous, culturally sensitive, and family oriented is essential to the optimal heath and developmental outcome of the patient who was born preterm.
In the United States, the Centers for Disease Control and Prevention (CDC) reports that preterm birth rates decreased from 2007 to 2014, in part because of a decline in the number of births to teenagers and young mothers. However, since 2016, preterm births are once again on the rise, the cause of which is largely unknown.
The preterm delivery rate is highest for black women and lowest for white women (14% and 9%, respectively). The increase in preterm births has occurred among late preterm newborns (>34 weeks’ gestation), who comprise 70% of preterm births. Reasons for the increased preterm delivery rates include increased use of artificial reproductive technologies (see Chapter 26), increased interest in elective cesarean section, and increased maternal age.
Although most preterm newborns are delivered at greater than 34 weeks’ gestation, these neonates are at increased risk for morbidity and mortality compared with neonates born at term. Additionally, many neonatologists routinely resuscitate neonates born at 23 weeks’ gestation, a gestation with a survival rate of approximately 25%. Very low-birth-weight (VLBW, <1,500 g [<52.9 oz]) and extremely low-birth-weight (ELBW, <1,000 g [<35.3 oz]) newborns are at risk for cerebral palsy, respiratory disease, hearing and vision problems, and intellectual disabilities. Furthermore, learning disabilities, attention-deficit/hyperactivity disorder, borderline to low IQ scores, psychiatric disorders or abnormalities in executive function, and visuomotor integration occur in more than 50% of VLBW infants, thereby com-plicating post-discharge care for these children. In 2007, the Institute of Medicine (now the National Academy of Medicine) estimated the annual societal cost of preterm birth at $26 billion and individual family cost of $2 million.
In utero, the placenta serves several functions, including promoting and regulating fetal growth, providing nutrients, and preventing infection by acting as a barrier. Delivery before 39 weeks of gestation halts this process, and these immature organs have functional limitations. Causes of preterm delivery can be maternal, the most common of which is pregnancy-induced hypertension, or fetal, the most common of which is premature rupture of membranes resulting from chorioamnionitis. Regardless of cause, these infants have special needs that should be addressed at every primary care visit.
The purpose of the health maintenance visit for preterm infants is the same as for other healthy children: to provide consistent preventive health care and education for patients and their parents. Preterm status, however, places children at risk for additional medical and neurodevelopmental conditions. Compared with children born full term, children born preterm have an average of nearly 3 times the number of well-child visits in the first year after birth and more hospital readmissions.
Almost one-third of preterm newborns are not brought in for their first scheduled outpatient appointment. Because failure to attend follow-up appointments has been associated with a higher rate of developmental delay, discussions about the importance of follow-up appointments are ideally initiated with the parent or caregiver before the infant is discharged from the neonatal intensive care unit (NICU).
It is imperative to review the entire medical history and hospital course before the initial visit and then discuss it with the family at the appointment. Ideally, the NICU should provide a discharge summary that includes the information listed in Box 43.1.
Any significant complications or concerns should be discussed with parents or caregivers at the earliest opportunity to assess their understanding of these issues and their expectations for improvement. Specifically, growth, nutrition, and developmental issues should be addressed at each visit (Box 43.2). Adequate or desirable weight gain should be explained to caregivers in terms of the infant’s current weight versus discharge weight. Infants younger than 6 months should gain an average of 20 to 40 g (0.7–1.4 oz) per day. To ensure continued weight gain, many preterm infants are discharged from the NICU on a 24-hour feeding schedule, which requires that they be fed at least every 3 hours. The necessity for this practice should be reevaluated during the first few weeks following discharge after infants have demonstrated adequate weight gain.
Box 43.1. Neonatal Intensive Care Unit Discharge Summary Information
1. Birth weight, gestational age, and significant prenatal and perinatal information, including delivery room details
2. Overview of the hospital course by system, including significant illnesses, events, surgical procedures, and pertinent radiographic and other diagnostic studies
3. Nutrition information and present feeding regimen
4. A list of current medications, including dosing intervals and, if appropriate, the latest serum drug levels
5. Immunizations administered during the hospitalization
6. Pertinent laboratory and diagnostic data, such as most recent hemoglobin level, newborn screening results, ophthalmologic and hearing screening information, neurosonography and magnetic resonance imaging results, and highest serum bilirubin level
7. Discharge physical examination, including most recent height, weight, and head circumference
8. Parental or other social concerns throughout patient’s stay in the neonatal intensive care unit
9. Problems remaining at discharge
10. All follow-up appointments
Box 43.2. What to Ask
Well-Child Care for Preterm Infants
•How much did the infant weigh when discharged from the hospital?
•Is the infant fed mother’s milk, or is the infant formula-fed? Is the infant on any special formula?
•How often and how much does the infant feed? How long do feedings take?
•Does the infant have any feeding problems (eg, pain, vomiting, gastroesophageal reflux)?
•Does the infant take dietary supplementation of vitamins and minerals?
•What developmental milestones has the infant reached? Does the infant roll over? Smile? Sit up?
•Does the infant seem to hear and see?
•Who cares for the infant? Is the primary caregiver getting enough rest?
•Does the infant have regional services and if so, which ones and how often?
•Where and in what position does the child sleep?
•Does the parent or caregiver have any concerns about growth, development, or nutrition?
•Is the infant on an apnea monitor and/or caffeine? Has the infant experienced any apneic episodes?
Developmental history is a critical component of the health maintenance visit. Parental expectations and observations should be noted, and any developmental concerns should be evaluated. The adjusted developmental age should be calculated by subtracting the number of weeks the infant was born preterm from the infant’s current chronologic age in weeks. The adjusted age should then be used for all formal and informal developmental assessments. The importance of correcting for preterm status until children are 2 years of age must be emphasized when discussing developmental progress and giving anticipatory guidance to parents or caregivers. It is important to know if the patient is receiving any regional services, which ones, and how often so an accurate recommendation can be made if it is necessary to increase these services.
A complete physical examination should be performed at each visit to monitor the status of associated medical conditions. All growth parameters (ie, weight, height, and head circumference) should be plotted on the growth chart for preterm newborns until approximately 50 weeks’ postmenstrual age and adjusted for preterm status on standard growth charts until age 2 years. Because catch-up head growth generally precedes catch-up weight and length, preterm infants may appear to have disproportionally large heads. The onset of accelerated head growth may begin within a few weeks after birth (36 weeks’ postconception) or as late as 8 months adjusted age. Average daily weight gain in grams per day should also be calculated and discussed with the parent or caregiver at every visit.
The size and shape of the head must be evaluated, especially if the infant has a history of intraventricular or intracranial hemorrhage or hydrocephalus. An increase in head circumference of more than 2 cm (0.8 in) per week should be cause for concern in these infants. In infants who have undergone neurosurgical treatment for hydrocephalus, ventriculoperitoneal shunt and tubing may be palpated. The head must also be evaluated for positional plagiocephaly, a condition caused by lying in the same position for prolonged periods of time. Visual abnormalities, such as strabismus, must be carefully ruled out by both physical examination and history because up to 20% of preterm infants may have an ophthalmologic problem (see Chapter 91). Oropharyngeal abnormalities, such as a palatal groove, high-arched palate, or abnormal tooth formation, may occur as a result of prolonged endotracheal intubation. Baseline intercostal, substernal, or subcostal retractions; wheezing; stridor; and tachypnea in former preterm babies with moderate to severe bronchopulmonary dysplasia (BPD), a form of chronic lung disease, should be documented. Infants with BPD have increased susceptibility to pulmonary infections leading to rehospitalization and may continue to exhibit poor lung function through adolescence.
Chest and back scars secondary to the placement of chest tubes or patent ductus arteriosus ligation should be noted. Adult female breasts may be affected if scarring occurs on or close to breast tissue. The umbilicus may appear hypoplastic as a result of umbilical catheter placement and suturing. Scars on the distal extremities from intravenous catheters and cutdowns may be evident.
The genitalia of all preterm infants should be examined closely for inguinal hernias. Inguinal hernia repair is often deferred until 60 weeks’ corrected gestational age unless incarceration risk is deemed high or the family lives far from a pediatric surgeon. Surgery is deferred because of concerns about adverse neurodevelopmental outcomes in children exposed to general anesthesia in the first months after birth, the high rates of postoperative apnea, and the occasional spontaneous closure in the first year after birth without intervention. If a hernia is surgically repaired under general anesthesia, the infant should be monitored for apnea for up to 24 hours postoperatively. The male scrotum should be examined for cryptorchidism, because at term gestation only 25% of testes are in the scrotum of males born preterm. By 1 year of age, more than 90% of testes are intrascrotal. A careful evaluation for developmental dysplasia of the hip should be performed until children are ambulatory, and hip ultrasonography (US) should be performed at 6 weeks of age for all breech deliveries (see Chapter 113).
A thorough neuromuscular examination is essential in children born preterm. Increased muscular tone, asymmetry, and decreased bulk should be noted along with the presence of any clonus or asymmetry of deep tendon reflexes. Inappropriate reflexes, such as a persistent Moro reflex or fisting beyond 4 months of age, should also be documented. Other abnormalities (eg, scissoring, sustained clonus) in the neurologic examination may become more apparent with age. The detection of subtle early findings is important so appropriate intervention services can begin as soon as possible.
In addition to the standard screening tests performed on all healthy infants and children during health maintenance visits, several laboratory studies are important for preterm infants. Such tests include a hemoglobin test and reticulocyte count to assess for anemia; electrolytes in infants with BPD on diuretics to detect abnormalities; and serum calcium, phosphorus, and alkaline phosphatase levels in infants with documented metabolic bone disease of prematurity.
Pulse oximetry is indicated for oxygen-dependent infants as well as those presenting with respiratory symptoms greater than baseline. Results from newborn screening tests, including auditory and ophthalmologic examinations, should be reviewed and repeated as indicated. Cranial US should be reviewed with caution, because nearly 40% of infants born weighing less than 1,000 g (35.3 oz) with normal head US findings develop cerebral palsy or developmental delay. Additionally, infants with grade 1 or 2 intracranial hemorrhage are at increased risk for developmental delay. Brain magnetic resonance imaging should be considered in infants born at less than 30 weeks’ gestation or in any infant with a concerning abnormal neurologic examination or abnormal rate of head growth.
Well-child care in relatively healthy preterm infants has 2 components. One is the provision of routine health care maintenance for infants and appropriate developmental anticipatory guidance for parents or caregivers. The other component involves the incorporation into each visit of treatment for chronic conditions that are sequelae of preterm birth. Health care maintenance should include the psychosocial well-being of the family, nutrition counseling, developmental surveillance, immunizations, and assessment of vision and hearing in addition to standard screening tests discussed previously. Outside resources concerning developmental delay can be reviewed with parents or caregivers. Care related to chronic conditions includes adjusting medication doses, such as diuretic therapy; weaning from supplemental oxygen; and discontinuing the apnea monitor.
Before hospital discharge, parents or guardians should be given anticipatory guidance that caring for a NICU graduate is challenging (Box 43.3). The American Academy of Pediatrics (AAP) recommends parental education as 1 of 6 critical components of discharge planning for any high-risk neonate and includes not only educating parents about the patient’s care but also identifying an additional caregiver who can assist with the demands of caring for the child at home. Preterm newborns have poorly organized sleep-wake cycles, resulting in more frequent awaking than term newborns. Additionally, preterm newborns have immature suck-swallow coordination, causing them to feed more frequently and for longer periods. Colic is reported twice as frequently in VLBW infants compared with infants born at term, and many are described as having difficult temperament until past their first birthday. Preterm infants also develop gastroesophageal reflux more often than full-term infants, which presents with such symptoms as irritability, respiratory problems, and postprandial vomiting.
The medical costs associated with the care of preterm infants often strain the family finances at a time when many women reduce their work schedules. Additional stressors include uncertainty about the long-term outcome of the child, guilt many women feel after delivering prematurely, and anxiety about future pregnancies. The difficulty of caring for these complicated, challenging children results in significant parental stress and can interfere with parents’ ability to properly bond with their babies. Health professionals should be alert to signs of a parent feeling overwhelmed, because a higher caregiving burden is associated with an increased incidence of child welfare reports, such as child neglect.
Box 43.3. Physician Support and Education of Parents of or Caregivers for Preterm Infants
•Understand parental/caregiver expectations.
•Legitimize parental/caregiver fears.
•Be a source of support and encouragement.
•Provide consistent, honest information.
•Assume the role of the overall coordinator of care.
•Provide referrals to outside resources, including respite care.