Care of the Late Preterm Infant

1. Care of the Late Preterm Infant Patricia A. Scott, MSN, APN, NNP-BC, C-NPT Vanderbilt University School of Nursing, Neonatal Nurse Practitioner Faculty Pediatrix Medical Group of Tennessee at Centennial Medical Center – The Women’s Hospital University of Tennessee Health Science Center DNP Student

2. Presentation Objectives • Discuss the definition and incidence of late preterm birth. • Discuss the incidence, risks for, and etiology of • respiratory distress in the late preterm infant. • Identify signs of hypo/hyperthermia. • Describe the physiology, assessment, and management • of hyperbilirubinemia and why the late preterm infant is • at increased risk. • Discuss why this population is at increased risk for • hypoglycemia and feeding difficulties.

3. Definition of the Late Preterm Infant • Infants born between 34 and 36 completed weeks of gestation • “Near term” thought to imply that these babies are “near enough” term to be physiologically the same (Engle, 2009)

4. Distribution of Preterm Births (CDC)

5. Morbidity and Mortality • Morbidity: not fully known • Mortality: 3 X higher than the term infant

6. What does the Late Preterm Infant Miss? • Vital period of maturation • Lung development • Brain maturation • Liver maturation • Vital period of growth • Body mass increases • Fat stores increase

7. Complications (Adamkin, 2009)

8. Late Preterm Care Delivery Issues • Longer hospital stays • Higher rate of readmission • Increased nursing care • Location of care varies

9. Most Common Complications • Respiratory distress • Temperature instability • Hyperbilirubinemia • Feeding challenges

10. Respiratory Distress

11. Respiratory Distress: Incidence • 35 to 36 week infants: 28.9% respiratory distress at birth compared to 4.2% of term infants • 35 to 36 week ventilated infants: RDS in 62%

12. Respiratory Distress • Delayed transition or respiratory distress? • Differential diagnosis includes: • TTN • RDS • Sepsis • PPHN • Congenital anomalies

13. Risk Factors for Respiratory Distress • Elective cesarean birth without the benefit of labor • Maternal complications • Fetal factors

14. Transient Tachypnea of the Newborn • Delayed reabsorption of lung fluid • Onset: 2 to 6 hours of life • Risk factors for TTN • Cesarean delivery • Precipitous delivery

15. Transient Tachypnea of the Newborn • Clinical presentation • Tachypnea • Grunting / flaring / retractions • Diagnostic studies • Blood gases • Chest x-ray • Septic work-up • Management / Outcome • Supportive care

16. Chest X-Rays

17. Respiratory Distress Syndrome • Immature lungs and surfactant deficiency • Onset: within minutes to hours of birth • Risk Factors • Prematurity • Cesarean delivery • Maternal diabetes • Second born twin • Perinatal asphyxia • Male gender

18. RDS: Clinical Presentation • Tachypnea • Grunting • Flaring • Retractions • Pallor or cyanosis • Decreased breath • sounds/fine rales • Hypotension • Decreased perfusion • Tachycardia

19. RDS: Diagnosis • Arterial blood gases • Hypoxemia • Respiratory acidosis • Chest x-ray • Infection should be ruled out

20. Chest X-Rays

21. RDS: Management • Provide a NTE • Oxygen support, as needed • Ventilatory support, as needed • Surfactant replacement therapy • As early as possible

22. RDS: Management • Fluid restriction • Monitor serum electrolytes • Minimal stimulation • Blood pressure support • Continued, comprehensive assessment

23. RDS: Outcome • Directly related to birth weight andgestational age • Affected by prenatal glucocorticoid treatment and surfactant replacement

24. Thermoregulation

25. Non-Shivering Thermogenesis • Cold stress → hypothalamus → epinephrine →brown fat metabolism • Function: heat production • Location: axilla, nape of neck, between scapulas, mediastinum, around the kidneys • Stores increase until 3-5 weeks postnatal life

26. Heat Transfer Mechanisms • Conduction • Convection • Evaporation • Radiation

27. Conduction • Heat transfer by direct contact • Varies with exposed surface area • Decreased ability to flex extremities • Decreased subcutaneous fat • Limited ability to VC peripheral blood vessels • Ways to minimize

28. Convection • Air currents move heat away from the body • Affected by ambient temperature, air flow velocity, and relative humidity • Ways to minimize

29. Evaporation • Liquid is converted into a vapor • Major source of heat loss at delivery/bathing • Losses through skin and respiratory system • Dependent upon air • speed and • relative humidity • Ways to minimize

30. Radiation • Transfer of radiant energy from the body • to objects without direct contact • Radiant warmer – heat gain • “Greenhouse effect” • Ways to minimize

31. Normal Temperature Ranges • Axillary temperature • Term: 97.9 – 99.5 ̊ F (36.5 – 37.5 ̊ C) • Preterm: 97.5 – 98.5 ̊ F (36.3 – 36.9 ̊ C) • Skin temperature • Term: 96.8 – 97.7 ̊ F (36 – 36.5 ̊ C) • Preterm: 97.2 – 99 ̊ F (36.2 – 37.2 ̊ C) • Rectal/tympanic not recommended

32. Radiant Warmers versus Isolettes • Advantages • Disadvantages • Wean to crib

33. Skin-To-Skin Care • Can be close to the • breast for feeding • Stable vital signs • and oxygenation • Improved sleeping • patterns and direct • social eye contact

34. Hypothermia: Clinical Presentation • Pale, cool to touch • Acrocyanosis • Respiratory distress • Apnea, bradycardia, central cyanosis • Irritability → lethargy • Progressive or chronic cold stress

35. COOLING Norepinephrine Release Brown Fat Utilization  Metabolic Rate Pulmonary VC Peripheral VC  R to L Shunting  O2 Delivery to Tissues Hypoxia Hypoxemia Free Fatty Acid Release  O2 Consumption Dependence on Anaerobic Metabolism ? DEATH Lactic Acidosis

36. Temp Instability: Differential Diagnosis • Arterial blood gas • Septic workup • Blood glucose • Electrolytes

37. Hypothermia: Treatment • Gradual re-warming • Prevent further heat loss • Frequent evaluation of temperature • Potential complications

38. Hyperthermia • Clinical presentation • Etiology • Treatment • Complications

39. Hyperbilirubinemia

40. Hyperbilirubinemia in the Late Preterm • ↑risk of significant hyperbilirubinemia • Immature liver • Higher bilirubin levels • Later bilirubin peak • Less vigorous feeding • 25% require phototherapy

41. Overview of Bilirubin Pathway

42. Neonatal Jaundice • Also called physiologic jaundice • Contributing factors: • Increased bilirubin load • Decreased hepatic uptake of bilirubin from plasma • Decreased bilirubin conjugation • Defective bilirubin excretion

43. Overproduction • Hemolytic disease • ABO and/or Rh incompatibility • RBC enzyme abnormalities • Glucose-6-phosphate dehydrogenase deficiency • PyruvateKinase Deficiency • Polycythemia • Extravascular blood • ↑ enterohepatic circulation

44. ↓ Excretion • ↓ hepatic uptake of bilirubin • ↓ bilirubin conjugation • Inadequate transport out of hepatocyte • Biliary obstruction

45. Overproduction + ↓ Excretion • Prematurity • Bacterial sepsis • Urinary tract infection • Intrauterine viral infections • Hypopituitarism • Hypothyroidism

46. Breastfeeding and Jaundice • Many advantages • Important to ensure good lactation support • Inadequate lactation associated with increased TSB level • Late preterm infant at risk for feeding problems • Less vigorous suck • Less stamina with feedings • Less coordination of suck and swallow • Less alert-awake states

47. Breastfeeding and Jaundice • May be prevented/reduced with frequent • feedings in first days of life • Late onset or prolonged hyperbilirubinemia • Affects 10-30% in 2nd to 6th week of life • Screen for risk factors to plan F/U • Unconjugatedbilirubin level > 12 mg/dl

48. Hyperbilirubinemia: History • Family • Obstetric • Neonatal • Decreasing gestational age • Apgar scores • LGA • Elevated PCV • Poor feeding

49. Hyperbilirubinemia: Clinical Presentation • Clinical presentation: • Jaundice may be the only presentation

50. Hyperbilirubinemia: Laboratory Data • Maternal and infant blood types, Rh, • and Coomb’s test • CBC/differential • Bilirubin levels