Infant born before completion of 37 weeks. Major problem of preterm newborn is immaturity of all systems.
Characteristics of preterm infant
Small & scrawny-minimal subq fat, large head, skin-bright pink, abundant fine lanugo hair, soft & pliable ear cartilage
Undescended testes, few scrotal rugae
Labia majora is under-developed, labia minora & clitoris are prominent.
Sucking is absent or weak; swallowing, gag & cough reflexes are absent or weak.
Respiratory alteration in preterm
Lungs not fully mature, lack of sufficient surfactant, increased respiratory distress syndrome.
Thermoregulation in preterm
Heat loss is major problem - prone to cold stress. Little subq fat, thinner more permeable skin
Clinical problems of preterm newborn
Apnea, Patent ductus arteriosis, RDS, intraventricular hemorrhage, hypoglycemia, necrotising enterocolitis, anemia, hyperbilirubinemai, infection
Born after 42 weeks
Post-mature associated factors
5 or more pregnancies, history of prolonged pregnancies
Post-mature infant characteristics
Absence of lanugo, little vernix, abundant scalp hair, long fingernails, cracked skin, wasted physical appearance (aging of placenta), depletion of subq fat
Large for gestational age (LGA)
Best known condition associated with LGA is maternal diabetes.
Birth trauma, increased chance of c-section & induction, hypoglycemia, polycthemia - increased # of RBC's
Small for gestational age (SGA)
Newborns at or below the 10th percentile, may be preterm or postterm, IUGR - intrauterine growth restriction
Maternal factors contributing to IUGR
Maternal factors - smoking, lack of prenatal care, age extremes (under 16 over 40) Maternal disease - heart disease, substance abuse, PIH
Environmental factors contributing to IUGR
High altitude, exposure to x-rays, excessive exercise, work related exposure to toxins
Placental factors contributing to IUGR
Small placenta, infarcted area, abnormal cord intersections, placenta previa
Fetal factors contributing to IUGR
Congenital infections, malformations, chromosomal syndromes
Complications of SGA newborn
Prenatal asphyxia, aspiration syndrome, heat loss, hypoclycemia, polycythemia
Prenatal asphyxia - SGA
Chronic hypoxia in utero
Aspiration syndrome - SGA
In utero - fetus can gasp during birth aspirating amniotic fluid into lower airways Hypoxia can lead to relaxation of anal sphincter & passage of meconium
Heat loss - SGA
Diminished subcutaneous fat, depletion of brown fat in utero, large surface area extremities not contracted
Hypoglycemia - SGA
Inadequate supplies of enzymes to activate gluconeogenesis, increase in metabolic rate in response to heat loss, infant will have routine one touch
Polycythemia - SGA
Increased # of RBC's - considered a physiologic response to hypoxic stress, produce more RBC's to carry O2, causes an increase in bilirubin
Nursing care for high risk newborn
#1-Support respiratory function, thermoregulation, protect from infection, hydration, nutrition
Respiratory distress syndrome (RDS)
Also known as Hyaline membrane disease. Result of absence or deficiency in the production of surfactant.
Scattered atelectasis, overinflation of some areas, grunting, cyanosis on room air, tachypnea, nasal flaring
Ventilator support, surfactant replacement therapy, In severe RDS - partial liquid ventilation
Too much O2 can cause retina damage