Neonatology for Primary Care

Deborah E. Campbell, Deborah E. Campbell

• Éditeur: American Academy of Pediatrics
• Année: 2020
• ISBN:
  9781610024099
• Édition: 2
• Sujet: Medizin
• Sous-sujet: Pädiatrische Medizin

The revised and updated second edition covers practical approaches to caring for healthy and high-risk newborns and infants. The book covers maternal and fetal health, care of the newborn after delivery, breastfeeding, follow-up care, common congenital anomalies, the newborn with a heart murmur or cyanosis, neurologic findings, primary care issues relating to newborns and infants requiring intensive care, and health and developmental outcomes. More than 40 chapters cover step-by-step guidance on what to do, when to admit, and when to refer. Recommendations and lists detailed references within each chapter. New in the second edition:
8 new chapters added including:

• Prenatal Diagnosis
• Fetal Interventions
• Optimizing Nutrition for the Preterm, Very Low-Birth-Weight Infant After Discharge From Neonatal Intensive Care
• Newborn Immunizations and Immune Prophylaxis
• Balancing Safe Sleep and Other Recommendations for Newborns
• Vascular Anomalies
• Endocrine Disorders Presenting in the Newborn Period
• Shared Decision Making Around Home Technologies

PART 1: PERINATAL HEALTH

1.PERINATAL PREVENTIVE CARE: FETAL ASSESSMENT

E. Rebecca Pschirrer, MD, MPH

George A. Little, MD, FAAP

2.ASSISTED REPRODUCTIVE TECHNOLOGIES, MULTIPLE BIRTHS, AND PREGNANCY OUTCOMES

Christie J. Bruno, DO, FAAP

Alaina Pyle, MD, FAAP

3.PRENATAL DIAGNOSIS .

Diana S. Wolfe, MD, MPH

Barrie Suskin, MD, FACOG, FACMG

4.FETAL INTERVENTIONS

Barrie Suskin, MD, FACOG, FACMG

5.MATERNAL DEPRESSION

Marian F. Earls, MD, MTS, FAAP

Perinatal Preventive Care: Fetal Assessment

E. Rebecca Pschirrer, MD, MPH, and George A. Little, MD, FAAP

Pediatricians, as primary care physicians and as subspecialist neonatologists, consult and work collaboratively with obstetric providers in preconception counseling, fetal risk identification, and peripartum decisions. Historically, pediatricians first saw their newborn patients in the nursery, but only after the events of pregnancy and delivery; today, their initial interaction with the expectant mother may be during a prenatal pediatric visit. In addition, pediatricians assume primary responsibility for resuscitation, stabilization, and ongoing care of the neonate from the moment of birth. Knowledge about fetal health includes appreciation of the interaction of the fetus with the mother, her partner (if any), health professionals, and society. Many examples exist of the capacity for health professionals in the field of fetal medicine, as part of preconception and prenatal care, to prevent or treat problems and improve outcomes.

Parents and health professionals have good reason to be concerned about the immediate and long-term effects of agents or processes on the fetus. Infections, such as rubella, can result in the loss of the fetus or in multisystem disease. The magnitude and severity of manifestations of maternal alcohol consumption, tobacco use, or substance use during pregnancy may be evident in the infant’s physical appearance or behavior in the neonatal period and throughout the child’s life course. Furthermore, problems may not appear until a subsequent generation. The effects of diethylstilbestrol, which historically was given to mothers to reduce the risk of pregnancy complication or abortion, were not recognized until the appearance of clear cell carcinoma of the vagina in female offspring 10 to 20 years later.¹

Growth and development are as important to fetal medicine as they are to pediatrics, of which study of the fetus is merely the first phase. Human growth and development must be regarded as a continuum that begins with conception. This chapter outlines some of the normal physical and interactive aspects of fetal existence, and then discusses selected pathophysiologic states that may adversely affect that existence.

Maternal Conditions That Affect the Fetus and Newborn

Many authorities have pointed to socioeconomic status and social environment as causes of fetal risk. Delineation of specific influences is difficult, but poverty is undoubtedly important, as are nutrition and hygiene. Intrauterine infection is more frequent in mothers of lower socioeconomic status. Emotional influences on fetal loss have been discussed; in addition, the possibility that medical or socioeconomic deprivation contributes to fetal loss cannot be discounted. Knowledge of a patient’s race, ethnicity, and language and communication needs can assist in the provision of patient-centered care, facilitate appropriate risk assessments, and improve perinatal outcomes. Socioeconomic status, immigration, and health literacy may further moderate the effect of race, ethnicity, and language. Quality maternity and perinatal care can be influenced by a health professional’s identification and understanding of the cultural beliefs and experiences of the pregnant woman and her family, and by the expression and understanding of health care needs communicated by patients.²

The risk of adult health disorders, particularly obesity and metabolic syndrome, can be markedly influenced by early life events, such as maternal preexisting and pregnancy-related health conditions and environmental exposures. These pregestational and gestational factors affect both prenatal and neonatal growth trajectories. Alterations in embryonic and fetal nutrition as well as endocrine status during gestation can result in developmental adaptations that produce permanent structural, physiologic, metabolic, and epigenetic changes, thereby predisposing an individual to adult cardiovascular, metabolic, and endocrine diseases, particularly metabolic syndrome.

Maternal Nutrition

Maternal nutritional disorders, including situations in which gross deprivation is not apparent, represent a definite risk to the fetus. The supply of substrate to the fetus for growth originates with the maternal circulation and passes through an interface with fetal tissue at the placenta. Placental insufficiency can result in fetal growth restriction (FGR) that is not of maternal origin. The relationship between maternal and fetal nutrition is complex. Maternal dietary changes usually do not directly or rapidly influence fetal well-being; thus, the positive or negative effects of changes in maternal nutrition are not easily recognized. Maternal weight is an important concern.

Traditionally, 2 types of nutritional deficiency have been conceptualized: general caloric or energy-related deficiency states and specific deficiencies. Deprivation of maternal caloric intake to the point at which fetal growth is markedly impaired also may be associated with specific deficiencies. If maternal caloric deprivation is severe, fertility is decreased.

Women whose prepregnancy weight is below standard for height tend to have babies whose weight is less than expected. Women with obesity tend to have heavier babies. Problems such as hyperemesis gravidarum can result in fetal caloric deprivation. The mother’s expression of eating disorders, which often start during late childhood and adolescence, is a possible fetal risk.

Specific deficiencies are well recognized; their risk to the fetus can be reduced through public health and individual clinical interventions. Vitamin deficiencies are of interest, and problems such as congenital beriberi (lack of thiamine) and infant calcium disorders (lack of maternal vitamin D) are of historical interest and decreasing incidence. Studies have confirmed that the occurrence of neural tube defects can be reduced by consuming folic acid, with the best protection achieved when 0.4 mg is ingested from at least 1 month before conception through the first month of pregnancy.³

Minerals are a major concern in pregnancy. Iodine deficiency is said to be the most common cause of preventable mental deficiency in the world; treatment during pregnancy protects the fetal brain, with later treatment being much less beneficial to neurologic status.⁴ Zinc deficiency may also be associated with anomalies. Maternal anemia caused by reduced availability of iron is well known; as a result, the fetus and infant can have low iron stores, making the infant susceptible to iron deficiency if intake after birth is inadequate.

Environmental Exposures

Adverse reproductive and developmental effects have been linked to environmental exposures. Vulnerability to toxic insult varies with the rate of cell division and with the developmental state of the exposed tissues; rapidly dividing cells, such as spermatocytes, neural stem cells, and embryonic cells, are especially susceptible. Adverse birth outcomes include preterm birth and low birth weight, congenital malformation, spontaneous pregnancy loss, and neurodevelopmental impairment. Environmental factors, such as radiation, chemicals, and drugs, affect people of all socioeconomic classes. A woman’s preconception or prenatal history should include review of history of alcohol and smoking as well as secondhand smoke exposure, illicit substance use, and other environmental exposures. These environmental toxicant exposures include mercury intake through fish consumption; well-water nitrate exposures; exposures to chemical, physical, and/or biologic hazards in the workplace or community; and lead and other toxicant exposures in the home. It is important to be aware that men are also vulnerable to environmental toxin exposures. Male-linked factors (referred to as male-mediated teratogens) that have been identified as having the potential to cause damage to offspring include cocaine, alcohol, some pesticides and solvents (eg, dibromochloropropane and trichloroethylene), and heavy metals such as lead and mercury. Reviewing exposure and risk factors for potential exposure is important, particularly for exposure to mercury, lead, pesticides, and endocrine disruptors, such as phthalates, bisphenol A, and polybrominated diethyl ethers.^5–7 Many excellent resources regarding environmental exposures are listed at the end of this chapter. Radiation exposure in mammals causes fetal death, growth restriction, and congenital malformation, with the central nervous system (CNS) commonly affected. The relationship between embryonic or fetal irradiation and carcinogenesis is unclear. Effects are both dose- and rate-related. Death during the preimplantation period, malformation during early organogenesis, and cell deletion and hypoplasia during fetal life form a general pattern in animal studies. Guidelines exist for limiting radiation to the embryo and fetus during occupational exposure or elective diagnostic techniques; however, dilemmas often arise from lack of foreknowledge about pregnancy, nonelective medical evaluations, and emotional factors. When necessary, a radiation physicist should be consulted.

Air pollution can originate from multiple sources, such as car exhaust, power plants, factories, fires, and fumes from solvents. Of the many chemical components that constitute air pollution, 4 of the most dangerous pollutants are sulfur dioxide, carbon monoxide, nitrogen oxides, and particulate matter. Exposure to air pollution early in pregnancy can affect fetal development. Similarly, exposure to pesticides (organophosphates) and herbicides through contact with contaminated air, food, and groundwater can result in FGR and anomalies, such as limb reduction deformities and urogenital and musculoskeletal defects. Neurotoxicity can result from prenatal and postnatal exposure to lead and methylmercury, leading to neurodevelopmental and cognitive impairments; cerebral palsy; sensory deficits (blindness, deafness); and deficits in attention, fine motor function, language, visual-spatial abilities, and memory.

Chemicals in the environ...