The Late Preterm Infant (34 0/7 to 36 6/7 weeks)

1. The Late Preterm Infant(34 0/7 to 36 6/7 weeks) Physical Exam & Physiologic Challenges EB

2. Why is this a problem? • The Late Preterm Infant (LPTI) population has increased by 30% since the 1980’s and accounts for as much as 75% of all preterm births in the US. • Possibly due to increasing maternal age, increased use of fertility treatments, multiple gestation, increasing obesity rates, maternal morbidity. • One study reports that a cost of $51,600 is associated with each late preterm birth. EB

3. Physical Exam Findings • LPTI should essentially have a normal exam, but may have some of these variations: • Increased lanugo, increased vernix, thin appearing skin, more visible veins • Boys may have high rising testes and a smoother appearing scrotum • Girls may have more prominent labia minora EB

4. Physical Exam Findings • Decreased creases on soles of feet • Lack of fully developed cartilage in ear • Decreased subcutaneous fat • May have decreased tone, with resting tone not in flexed position • Most of the differences between a full term and late preterm infant are things you can’t see during a routine physical exam! EB

5. Risks to the Late Preterm Infant • Excessive sleepiness • Excessive weight loss • Feeding problems • Hyperbilirubinemia • Hypoglycemia • Respiratory distress • Sepsis • Hypothermia and temp instability • ED visits and readmissions • Development delay • Increased medical costs EB

6. Physiologic Challenges: Thermoregulation • Increased risk for COLD STRESS: • Less subQ fat to insulate and less brown fat/adipose tissue to generate heat • Immature skin does not function well as a barrier for evaporative heat loss • High surface area to body mass ratio • Higher metabolic rate and little reserve • Less muscle tone and activity EB

7. Cold Stress • Can lead to metabolic acidosis, increased metabolic rate, pulmonary vasoconstriction • Signs and symptoms may include: apnea, bradycardia, lethargy, poor tone, mottled or pale skin. • May contribute to poor transitioning and lead to unnecessary sepsis work ups. EB

8. Minimizing Cold Stress • Goal: neutral thermal environment in which infant maintains temp without increased O2 or glucose/energy demand. • Drying skin and hair with warm blankets after delivery and placing skin to skin • Swaddle in 2-3 blankets • Use of hats • Use radiant warmer as needed EB

9. Thermoregulation:Clinical Pathway Interventions • Increased frequency of VS and temp checks • Ensure neutral thermal environment • Frequent skin to skin • If not skin to skin, keep infant dressed with hat on and wrapped in 1-2 blankets • Continue delayed 1st bath • Hypothermia: slow rewarming with radiant warmer, check blood sugar. EB

10. Physiologic Challenges:Breathing • Development of terminal air sacs in the lungs continues in utero during weeks 34-36 6/7. • Alveoli are maturing and becoming lined with Type 1 epithelial cells. These cells are closer in proximity to capillaries to help with gas exchange. • Type 2 cells develop during this time also to secrete surfactant. • Immaturity can lead to poor lung compliance and increased pulmonary resistance. EB

11. Physiologic Challenges:Breathing • Less effective clearance of amniotic fluid • Difficult to maintain alveolar expansion • More likely to experience RDS, TTN, even respiratory failure. • Other risks include apnea, bradycardia, ALTE’s, SIDS EB

12. Respiratory Distress • Usually manifests in first hours after birth with grunting, flaring, tachypnea, retractions. • Risk increases if c-section delivery with no labor. • During labor, catecholamines are released which help with absorption of lung fluid and surfactant release helping to improve lung compliance. EB

13. Breathing:Clinical Pathway Interventions • More frequent VS and respiratory assessments • Pulse ox screenings with VS • Parent education regarding respiratory distress • If RR >60 breathes per minute, consider holding feeding temporarily EB

14. Physiologic Challenges: Energy and Metabolism • Regulation of temperature helps minimize risk of hypoglycemia • All babies have physiologic nadir of blood sugar between 1-2 hours of life. This decrease in blood sugar is more pronounced in the late preterm than full term infant. • Should have blood sugars monitored and have first feeding within 1 hour of life (if stable) and no less than every 3 hours after EB

15. Physiologic Challenges:Hypoglycemia • LPTI 3x more likely to suffer from hypoglycemia than term infants. • Decreased glycogen stores and adipose tissue • Immature liver enzymes less able to increase glucose production through gluconeogenesis • Immature pancreatic beta cells may secrete more insulin than necessary • Medical complications increasing demand. EB

16. Hypoglycemia • Sources vary as to what is a ‘normal’ glucose in infants. Reported ranges: 40-45 to 55-70. • 80% of total glucose is consumed by the brain • LPTIs cannot effectively use other forms of fuel such as ketones, amino acids, and glycerol to raise blood sugar. • This, combined with immature protective systems in the brain, make the LPTI more at risk for adverse neurologic outcomes related to hypoglycemia. EB

17. Energy and Metabolism:Clinical Pathway Interventions • Hypoglycemia protocol • Assess weight loss daily • Assess ability to eat safely: coordination of suck, swallow, breathe. • Early and effective feedings EB

18. Physiologic Challenges:Feeding & Nutrition • Risk for poor feeding & inadequate caloric intake • Mom at risk for delayed/low milk production, weak suck, small mouth, high energy demand with low stores, sleepy, uncoordinated suck/swallow/breathe, lack of hunger cues, ineffective milk transfer. • These mother baby dyads need extra help: • Assistance with latch, education on frequency of feeding and hunger cues, use of nipple shield, pumping, supplementing. EB

19. Feeding and Nutrition:Clinical Pathway Interventions • Early and effective feedings with assessment of milk transfer • Initiate feeding plan based on infants method of feeding. Feeding plan for discharge. • Assist mother with learning to pump. • Early supplementation or increased caloric formula for excessive weight loss as indicated in feeding plan EB

20. Physiologic Challenges:Hyperbilirubinemia • LPTIs have a later peak (day 5-7) and prolonged phase of elevated bilirubin. • Low milk intake and transient slower intestinal motility leads to slowing passage of meconium • This increases enterohepatic circulation and reuptake of bilirubin • Bilirubin conjugating enzyme activity is lower • Increased risk of readmission for jaundice. • Risk of kernicterus is higher EB

21. Minimizing Hyperbilirubinemia • Optimize feeding with increased milk intake • Consider early supplementation • Assist with meconium clearance • Prevent excessive weight loss • Keep moms and babies together and maximize stay in hospital • Monitor with TC or serum bilirubin checks • Start phototherapy at a lower threshhold. EB

22. Hyperbilirubinemia:Clinical Pathway Interventions • Serum bilirubin at 24 hours of life (obtain with newborn screen). • Early and effective feedings • Daily assessment of jaundice with clinical assessment and TC/serum checks • Maximize length of hospital stay EB

23. Physiologic Challenges:Immature Nervous System • Significant brain growth and maturation occurs in last 6-8 weeks of pregnancy • 34 weeker has 50% less brain volume than term infant • LPTI less able to control state regulation and regulate internal processes. • Decreased tone, positional apnea, disorganized suck/swallow/breathe, frequent startling, more spitting up, unpredictable response to stimuli (even when attempting to soothe) • Minimizing or clustering stimulation is helpful EB

24. Physiologic Challenges:Immature Nervous System • Because of the significant amount of brain growth, neuronal connections to be made, and overall nervous system development that still is occuring, the LTPI is at a higher risk for long term neurodevelopmental delays. • In severe cases, IVH and PVL, although this is not common EB

25. Immature Nervous System:Clinical Pathway Interventions • Encourage skin to skin • Minimize unnecessary stimulation • Allow uninterrupted periods of rest • Parent education of behavioral states, infant soothing techniques, developmental milestones, etc. EB

26. Physiologic Challenges:Immature Immune System • Less maternal antibody transfer across placenta as compared to full term infant. • Other risk factors are common to all infants, although preterm infants more susceptible. • Chorioamnionitis, ROM >18h, maternal fever. • Signs and symptoms can be vague. • Temp instability, respiratory distress, hypoglycemia, lethargy, jaundice, irritability, feeding difficulties. EB

27. Immature Immune System:Clinical Pathway Interventions • Handwashing! • GBS protocol • Evaluate maternal and infant risk factors that may predispose infant to infection • No sick contacts EB

28. LPTI Discharge Considerations:Suggestions from the AAP • Demonstrate weight gain • Competent feeding by parents preferred method • Able to maintain body temperature while dressed in open crib with normal room temp • Stable cardiorespiratory function • Parents educated on special needs of LPTI and competent in all care • PCP identified and close follow up arranged EB

29. Additional UNC LPTI Discharge Considerations • Discourage any discharge prior to 48 hours of age. • Feeding plan in place prior to going home • Late preterm specific parent education • PCP follow up within 24 (or 48) hours of discharge required. • Consider outpatient follow up with LC 24-48 hours after discharge. EB

30. References • Darcy, A. (2009). Complications of the Late Preterm Infant. Journal of Perinatal Neonatal Nursing, 23 (1), 78-86. • Hubbard, E., Stellwagen, L., & Wolf, A. (2007). The Late Preterm Infant: A Little Baby with Big Needs. Contemporary Pediatrics . • Mally, P., Bailey, S., & Hendricks-Munoz, K. (2010). Clinical Issues in the Management of Late Preterm Infants. Current Problems in Pediatric and Adolescent Healthcare, 40 (21), 218-233. • National Guideline Clearinghouse. (2010). Assessment and Care of the Late Preterm Infant. Evidence-based clinical practice guideline. • Oklahoma Infant Alliance. (2010, September). Caring for the Late Preterm Infant. A Clinical Practice Guideline. EB

31. References • University of California, San Diego Medical Center. (2006, October). Late Preterm Infant Policy Statement. • Raju, T., Higgins, R., Stark, A., & Leveno, K. (2006). Optimizing Care and Outcome for Late-Preterm (Near Term) Infants: A Summary of the Workshop Sponsored by the National Institute of Child Health and Human Development. Pediatrics (118), 1207-1214. • Ramachandrappa, A., & Jain, L. (2009). Health Issues of the Late Preterm Infant. Pediatric Clinics of North America (56), 565-577. • Verklan, M. T. (2009). So, He's a Little Premature...What's the Big Deal? Critical Care Nursing Clinics of North America, 21, 149-161. EB