Neonatal Pediatrics PDF

PEDIATRICS 1 NEONATAL PEDIATRICS ANA MARIE R. MORELOS, MD forms of external stimuli. Because infants thrive physically...

PEDIATRICS 1 NEONATAL PEDIATRICS ANA MARIE R. MORELOS, MD forms of external stimuli. Because infants thrive physically and psychologically only in the context of their social OUTLINE relationships, any description of the newborn’s developmental status I. Introduction has to include consideration of the parents’ role as well. (from 2023 a. Neonatology trans) b. Perinatology II. Fetal Growth and Development a. Embryo A. NEONATOLOGY b. Fetus ✎ Neonatology is a major subspecialty of pediatrics (from c. Aspects of Fetal Development 2024 trans) d. Milestones of Prenatal Development III. History in Neonatal Pediatrics Must include or consider Perinatal and Neonatal Medicine a. Demographic and Social Data Focuses on caring for the newborn infant (first 4 weeks.) b. Maternal Medical Conditions Neonate- 20 weeks to 1 month of life c. Previous Maternal Reproductive Problems Includes caring for the fetus beginning from 20 weeks d. Events Occurring in the Present Pregnancy gestation to 28 days of postnatal life e. Fetal Risk Factors f. Description of the Labor and Delivery IV. Fetal Physiology Prior to Transition B. PERINATOLOGY a. Fetal Circulation Maternal fetal medicine that focuses on caring for the fetus b. Fetal Pulmonary Status c. Endocrine Development and mother during pregnancy d. Hematologic Development 20-28 weeks gestation (fetal viability) to 4 weeks postpartum. V. Transition to Extrauterine Life ✎ ☤ Mabubuhay na yung fetus pag na deliver na siya (from a. Physiologic Changes 2024 trans) b. Neonatal Period Main concern is to provide for the best maternal/neonatal VI. Routine or Immediate Newborn Care outcome a. APGAR A healthy newborn is likely to come from a healthy b. EINC c. Assessment of Gestational Age pregnancy. d. Developmental Reflexes Continue to always consider the mother and the fetus. e. Physical Examination VII. Summary VIII. References II. FETAL GROWTH & DEVELOPMENT IX. Review Questions A. EMBRYO LEGEND Embryo: From conception until before the 8th week Human embryo: a discrete entity that has arisen from: Must Lecture Book ○ The first mitotic division when fertilization of a Know [lec] [bk] human oocyte by a human sperm is complete; or ○ Any other process that initiates organized development of a biological entity with a human OBJECTIVES nuclear genome that has the potential to develop Define terms: Neonatology and Perinatology up to, or beyond, the stage at which the primitive Discuss fetal growth and development streak appears; and has not yet reached 8 weeks Discuss history in neonatal pediatrics of development since the first mitotic division Discuss the transition from intra to extra uterine life Discuss physical examination of the neonate B. FETUS Discuss APGAR scoring Fetus: From the 9th week after conception until term while in Discuss essential intrapartum newborn care the uterus Discuss resuscitation at birth Fetal period: In humans, the development week 9 to 36 is Discuss vital signs, anthropometrics, and gestational age the fetal stage (second and third trimester) and during this Discuss developmental reflexes time organs formed in the embryonic period continue to Discuss subsequent newborn care develop and the fetus grows in size and weight Discuss newborn screening tests Discuss behavioral patterns and other concerns in the newborn period C. ASPECTS OF FETAL DEVELOPMENT Introduce conditions that will need specialized care for the ☤ The developing fetus is affected by social and newborn (red flags)INTRODUCTION environmental influences, including maternal nutritional status; substance use (both legal and illicit); and psychologic trauma I. INTRODUCTION ☤ The psychologic alterations experienced by the parents ✎ Transition from intra to extra uterine life during the gestation profoundly impact the lives of all ✎ APGAR, Ballad Score members of the family ✎ EINC & Comprehensive newborn care ☤ The complex interplay among these forces and the ✎ Vital signs, anthropometric measurements, reflexes somatic and neurologic transformations occurring in the fetus ✎ Sleep patterns, bowel & urinary patterns influence growth and behavior at birth, through infancy, and ✎ Newborn screening, medications, immunizations potentially throughout the individual's life ✎ The newborn (neonatal) period begins at the birth Four important points: (regardless of gestational age) and includes the 1st month of ○ (1) Somatic: Embryonic & Fetal periods life. During this time, marked physiologic transitions occur in ○ (2) Neurologic all organ systems, and the infant learns to respond to many ○ (3) Behavioral [PEDIA] Acerimo, Manalo, Manaloto TH Navarro Page 1 of 13 NEONATAL PEDIATRICS ○ (4) Psychologic changes in parents 13 B: Breathing and swallowing motions appear D. MILESTONES OF PRENATAL DEVELOPMENT 17 B: Grasp reflex appears WEEK DEVELOPMENT 20 S: Usual lower limit of viability; weight 460 g; 1 S: Fertilization and implantation (until about Day 6) length 19 cm; primitive alveoli formed, Embryonic period begins (Blastocyst) surfactant production begins B: the full range of neonatal movements can be 2 S: Endoderm and ectoderm appear (bilaminar observed (☤ when you do an ultrasound) embryo) 25 S: Third trimester begins; weight 900 g; length 3 S: First missed menstrual period; mesoderm 24 cm. Weight triples, body stores of protein, appears (trilaminar embryo: ☤ endoderm, fat, iron, and calcium increase. ectoderm, mesoderm): Somites begin to form: N: Neuronal migration complete but neural tube, blood vessels, heart tubes differentiation continues, rapid growth of N: Neural plate appears on the ectodermal neurons and glia, axons and dendrites form surfaces synaptic connections at a rapid pace making ✎ forerunner of the brain and CNS (from the CNS vulnerable to teratogenic or hypoxic 2024 trans) influences throughout gestation. ☤ Note: 3rd trimester onwards: rapid growth of 4 S: Folding of embryo into human-like shape; neurons and glia: needed in shaping of the arm and leg buds appear; crown-rump length 4- brain and neuronal circuits, formation of myelin 5mm sheaths, maintenance of neural pathways. N: Infolding produces a neural tube that will B: During the 3rd trimester, fetuses respond to become the CNS and a neural crest that will external stimuli with heart rate elevation and become the PNS. Neuroectodermal cells body movements which can be observed with differentiate into neurons, astrocytes, ultrasound. Fetal movement increases in oligodendrocytes, ependymal cells. Microglial response to sudden auditory tone but cells are derived from the mesoderm decreases after several repetitions. (This is ☤ Neurodevelopment in 4th week called habituation, a basic form of learning) 5 S: Lens placodes (future eyes), primitive 28 S: Eyes open; fetus turns head down; weight mouth, digital rays on hands 1,000- 1,300 g N: 3 main subdivisions of forebrain, midbrain, B: Grasp reflex now well developed and hindbrain are evident. The dorsal and ventral horns of the spinal cord have begun to 38 Term (36 weeks is considered term already) form, along with the peripheral motor and N: At Birth structure of the brain is complete. sensory nerves. Myelination begins at However, many cells will undergo apoptosis midgestation and continues for years. (cell death). Synapses will be pruned back substantially, and new connections will be 6 S: Primitive nose, philtrum, primary palate made. ✎ Pruning refers to the synapses being cut in order to develop 7 S: Eyelids begin; crown-rump length 2 cm, brain growing rapidly 8 S: Ovaries and testes distinguishable, III. HISTORY IN NEONATAL PEDIATRICS Rudiments of all major organ systems have developed N: The gross structure of the nervous system “What should we know in anticipation of a neonate’s has been established. On a cellular level, extrauterine existence?” neurons migrate outward to form the 6 cortical Neonatal period layers. ○ A highly vulnerable time as infants complete the ☤ first 7-8th weeks are very important because many physiologic adjustments required for this is where your development is so fast extrauterine existence involving the neuro and somatic. ○ This transition is uneventful for most full-term infants. ○ Management of the newborn should focus on 9 S: Fetal period begins; crown-rump length parental anticipatory guidance and early detection 5 cm; weight 8 g of conditions or complications that carry risk of morbidity or even death of newborns 10 S: face is recognizably human, the midgut Assessment of the newborn should begin with a review of returns to the abdomen from the umbilical cord, the maternal and family history, the pregnancy, and the rotating counterclockwise to bring the stomach, delivery small intestine, and large intestine into their Details of this history should include the following normal positions. information, which will guide further evaluation and management in the newborn period, to know more as we 12 S: External genitals distinguishable; lung anticipate the coming of the neonate development proceeds. B: Start of behavioral evidence of neural A. DEMOGRAPHIC AND SOCIAL DATA function: reflexive responses to tactile stimulation develops in craniocaudal sequence. [PEDIA] Acerimo, Manalo, Manaloto TH Navarro Page 2 of 13 NEONATAL PEDIATRICS Socioeconomic and social data C. PREVIOUS ○ Socio-eco-cultural risks: indigenous people, slum MATERNAL AND REPRODUCTIVE dwellers, mothers with low educational status, adolescence, lack of support group, poverty, PROBLEMS domestic violence, unwanted/unplanned pregnancy, substance abuse, poor coping skills Nullipara/Multipara (>5 children) ○ Socio-eco concerns: housing, food insecurity, Short interpregnancy interval access to health care – warrant social worker Uterine/ cervical anomalies evaluation ○ Stillbirth Age (2000 mL amniotic fluid volume on 3rd ○ The fetus is spared from brief episodes of trimester maternal nutritional deprivation. ○ Polyhydramnios is associated with the following ○ When malnutrition is severe and chronic, growth mechanisms: potential is restricted due to lack of nutrients. Interference with fetal swallowing and Iron deficiency: sub-optimal growth of fetus reabsorption of amniotic fluid - due to Iodine deficiency: limits intellectual potential of the newborn fetal neuromuscular dysfunction, Folate deficiency: neural tube defects in fetus obstruction of fetal GIT Mothers with PKU - unable to metabolize phenylalanine. Fetal polyuria - due to uncontrolled ○ Must balance phenylalanine intake of the mother, maternal DM, fetal renal disease, fetal ensuring that the fetus gets enough essential anemia, fetal heart failure amino acids. Congenital anomalies - neural tube ○ Excessive accumulation of phenylalanine is toxic defects, cleft lip/palate, diaphragmatic to the fetus' brain and may also cause miscarriage hernia, adenomatoid lung malformation and congenital cardiac malformations. Syndromes - achondroplasia trisomy 18 Maternal medications, toxins, teratogens and 21, Klippel-Feil, TORCH, fetal ○ recreational drugs, anticonvulsants, antibiotics, hydrops hormones, anticancer drugs, carbon monoxide, Other conditions PCBs, mercury, phthalates Oligohydramnios - 100 Fetal hemoglobin has high oxygen affinity for better oxygen uptake at the placenta Babies still get oxygen through on-going erythropoiesis HEMATOLOGIC CHANGES and erythropoietin that leads to RBC production and After birth, there is a decreased production of fetal eventually oxygen uptake hemoglobin Concomitant increase in hemoglobin β chain production Normal levels of adult hemoglobin achieved by 4-6 months V. TRANSITION TO EXTRAUTERINE LIFE of age A. PHYSIOLOGIC CHANGES CARDIAC EVENTS METABOLIC CHANGES After delivery, progressive increase in metabolic rate Increased systemic vascular resistance with separation from ○ Slowly in preterm infants the low-resistance placental vasculature To maintain blood glucose levels after separation from the ○ When the umbilical cord is clamped, the placenta low-resistance vascular bed of the placenta is ○ Surge in catecholamine and glucagon level and disconnected, leading to an increase in the decrease in insulin amounts newborn’s systemic vascular resistance ○ Gluconeogenesis and glycogenolysis in the liver ○ The increase in systemic vascular resistance leads ensure stable blood glucose until oral intake to a rapid and transient increase in cerebral blood volumes improve over the first few days after birth flow. Increased oxygenation and decreased blood Ketone bodies and lactate provide added energy for the flow leads to closure of the fetal cardiac shunts brain Leads to closure of right-to-left shunts Hepatic ketogenesis increase after the 12th hour ○ Foramen ovale Cortisol levels peak after delivery Closes when left atrial pressure is ○ Combined action of cortisol and thyroid hormones greater than right atrial pressure activate sodium channel activity which drives The pressure within the LA then resorption of lung fluid increases because of the increased Increased production and release of catecholamines, distal aortic pressure and the greater renin-angiotensin, and vasopressin amount of blood returning to the LA from ○ Increases cardiac output the lungs. With the left atrial pressure ○ Increases plasma glucose being greater than the right atrial ○ Increases free fatty acids pressure, the flap across the foramen ovale closes TEMPERATURE REGULATION ○ Ductus arteriosus At birth, infants covered in liquid (☤ amniotic fluid), resulting Left-to-right flow within minutes of in potential heat loss via evaporation ventilation then closure over days ○ Hypothermia can ensue due to conduction, Oxygenation of the ductus arteriosus convection, radiant heat losses further leads to increased calcium That’s why it’s very important for babies channel activity resulting in functional to be kept warm at birth closure. Smooth muscle cells of the Neonates with a higher body surface area, limited capacity to ductus arteriosus respond to increased generate heat via shivering, and decreased subcutaneous oxygen with inhibition of potassium fat for insulation channel activity, also causing ductal Brown adipose tissue lipolysis triggered by norepinephrine constriction can generate heat and peripheral vasoconstriction can PULMONARY CHANGES minimize heat loss Rapid lowering of pulmonary vascular resistance with onset Thyroid hormones surge after birth, possibly in response to of ventilation and increased oxygen exposure the relatively cold extrauterine environment ○ There is high vascular resistance during fetal life B. NEONATAL PERIOD but with delivery of newborn, there is now the onset of ventilation and increased oxygen Functionally stable circulatory status at 1 week exposure because pulmonary vascular resistance Anatomic closure of patent ductus arteriosus in 1-2 weeks is lowered Foramen ovale may remain open but without flow [PEDIA] Acerimo, Manalo, Manaloto TH Navarro Page 5 of 13 NEONATAL PEDIATRICS One circulatory circuit similar to adult