Update: Late preterm infants – a population at risk

1
Update Late preterm infants a population at
risk

• Susan Landers MD, FAAP, FABM
• Pediatrix Medical Group
• Seton Medical Center Dell Childrens Medical
  Center of Central Texas
• Austin, TX

2
Preterm births in Texas 1994-2004 National
Center for Health Statistics, final natality
data Retrieved 12/03/2007 from
www.marchofdimes.com/peristats.
3
Low birth weight infants born in Texas
1994-2004 National Center for Health Statistics,
final natality data Retrieved 12/03/2007 from
www.marchofdimes.com/peristats.
4
Preterm births in US 2004 National Center for
Health Statistics, final natality data Retrieved
12/03/2007 from www.marchofdimes.com/peristats.
5
Clinical care issues for preterm infants

• Site of care (transitional nursery vs. NICU)
• Eye care, Vitamin K
• Skin care, bathing, clothing
• Weighing (lbs vs. grams)
• Sleep position
• Skin-to-skin holding
• Hepatitis immunization
• Metabolic/state newborn screening
• Hearing screening
• Circumcision
• Car seat study

6
Clinical care challenges for late preterm
infants

• Transitional difficulties
• Hypothermia, temperature instability
• Hypoglycemia
• Respiratory distress (TTN RDS)
• Hyperbilirubinemia
• Poor breastfeeding
• High risk for re-hospitalization

7
Golden Rule Late preterm infants are not term
babies. If you expect them to act like term
babies, you will be disappointed.
8
Definitions

• Late preterm babies born 34 0/7 to 36 6/7 wk.
  gestation (after onset of LMP)
• Near-term babies born 35 0/7 to 36 6/7 wk.
  gestation
• Big preemies born 34 to 36 wk. gestation
• Borderline term babies born 37 0/7 to 37 6/7
  wk. gestation
• Term babies born 37 0/7 to 41 6/7 wk.

AAP, ACOG, WHO, NIH
9
Reasons for recent increase in preterm birth
rates

• Older maternal ages at delivery
• Increased use of assisted reproductive
  technologies
• (IUI, IVF)
• More multiple gestations
• (mean gestation at del twins 35.3, triplets
  32.2 wks)
• Increasing rates of medical indications for
  C-section
• PPROM, preeclampsia, diabetes, chorioamnionitis
• Increasing rates of labor inductions

10
Davidoff et al. Semin Perinatol 2006 309
11
2002 Infant Mortality Rates in US per 1,000 live
births
Martin et al. Births final data for 2003. Nat
Vital Stat Rep. 200554(2)1-116.
12
Higher rates of mortality

• Late preterm infants, compared to term infants
• Early neonatal deaths (0-6 days) RR 5.2
• Late neonatal deaths (7-28 days) RR 2.9
• Post-neonatal deaths (gt28 days) RR 2.0
• Total infant mortality (0-1 year) RR 2.5
• Causes of death
• Congenital anomalies, infections,
  asphyxia-related disorders, respiratory failure,
  SIDS external trauma

Kramer, et al JAMA 2000284843. Canadian US
births from 1985 1995. (n US singletons
3,866,513 Canada 726,435)
13
Clinical outcomes in near term babies

Wang et al, Pediatrics 2004114372-376. Mass.
Gen. Hosp. n245.
14
Late preterm babies respiratory morbidity

Am J Ob Gyn 1992166 1629-45. Am J Ob Gyn
1996174525-28. Biol Neonate 1998747-15. Europe
an J Ob Gyn 2001989-13.
15
Late preterm babies morbidity in those with
early respiratory distress

• Suspected sepsis 27
• Antibiotic Rx gt 7 days 33
• Apnea, bradycardia, desaturation 30
• Hypothermia, temp instability 98
• Hypoglycemia 18
• Feeding difficulties 27
• NG or OG feedings 45
• Phototherapy 57
• NICU stay (days) 10

Am J Obstet Gynecol 20031891053. Case Western,
n150
16
Late preterm babies morbidities in those
without respiratory distress

• Suspected sepsis 3
• Antibiotic Rx gt 7 days 7
• Apnea, bradycardia, desaturation 5
• Hypothermia, temp instability 57
• Hypoglycemia 9
• Feeding difficulties 35
• NG or OG feedings 21
• Phototherapy 30
• NICU stay (days) 7

Am J Obstet Gynecol 20031891053-1057.
17
Late preterm infants complications of
prematurity during birth hospitalization
Engle, Tomashek, Wallman COFN. AAP Clinical
Report. Pediatr 20071201390-1401.
18
Neutral thermal environment

• Body temperature at which babys oxygen
  consumption is minimized
• Heat loss/heat transfer
• Radiant
• Conductive
• Evaporative
• Convective
• Nonshivering chemical thermogenesis
• Brown fat regulates
• Consumes O2 and glucose

19
? Risk of hypothermia characteristics of
preterm infants

• Thin skin (insensible water loss)
• Decreased subcutaneous fat (insulation)
• Large BSA (heat loss)
• Decreased glycogen stores
• Smaller brown fat stores
• Less ability to attain flexion position
• Increased energy requirements for growth

20
Neutral thermal environment

• Hypothermia lt 37 weeks gestation
• Consumes substrate (glucose) oxygen
• Adds stress increases metabolic rate
• Causes lethargy, hypotonia, weak suck, poor
  feeding
• Treatment
• Clothing blankets, hats
• Radiant warmer v. incubator temperature control
• Servo-controlled to skin (36-36.5C or 96.8-97.7F)
• Servo-controlled to ambient air (manual control)
• Relative humidity room temperature
• Skin-to-skin care for enhanced breastfeeding
• Merenstein GB and Gardner SL, Handbook of
  Neonatal Intensive Care. Third edition 1993.
  Mosby Yearbook, pp 100-114.

21
Infants at risk for hypoglycemia
Incidence

• LBW preterm 15 - 20
• SGA 20 - 30
• LGA 8 - 10
• IUGR 20
• IDM 10 - 30
• Perinatal stress 5 - 10

22
Clinical presentation of hypoglycemia

• Asymptomatic (common)
• Symptomatic (non-specific)
• Abnormal respirations tachypnea, apnea,
  respiratory distress, cyanosis
• Cardiovascular signs tachycardia, bradycardia
• Neurological signs jittery, lethargic, poor
  suck, temperature instability, irritability,
  seizures
• Hypothermia

23
Etiology of hypoglycemia in preterm infants

• Low glycogen reserves, depleted quickly
• Immature hepatic enzymes for gluconeogenesis
• Unregulated insulin production during
  hypoglycemia /- hyperinsulinism
• Inability to mount ketogenic response to
  hypoglycemia
• Preserved plasma concentrations of
  catecholamines increased cerebral blood flow

24
Hypoglycemia management (ABM)

• Selective screening of glucose preferred
• Institutional protocols
• Initial screen within 30 to 60 min. of age
• If baby symptomatic, do blood glucose in addition
  to screen.
• Individualize screening schedules

25
Hypoglycemia management

• Some babies require testing every hour until
  glucose is normal
• Once glucose is stable, screen glucose every 2 to
  4 hours, or prior to feedings
• Offer early feeds of breastmilk, or donor milk,
  or formula
• Feed every 2 to 3 hours with breastmilk /-
  formula
• ABM clinical protocol _at_ www.bfmed.org
• Breastfeeding Med. 2006 1(3) 178-184.

26
Feeding issues for late preterm babies

• Temperature stability
• Neurological maturity function
• Oral-motor coordination
• Cardio-respiratory control
• Brainstem respiratory centers
• Coordinated feeding behavior
• Suck-swallow-breathe

27
Practical feeding issues for late preterm babies

• Immature sucking efficiency
• Weak sucking pressure
• Low sucking frequency
• Immature swallowing
• Abnormal tongue movements
• Breathing abnormalities
• Oxygen desaturations
• Uncoordinated suck-swallow-breathing pattern

28
Feeding behavior in late preterm infants -
maturation in sucking variables
Mizuno, Ueda. J Pediatrics 200314236-40. n24
bottle-feeding infants
29
Feeding behavior in late preterm infants -
maturation in sucking variables
Mizuno, Ueda. J Pediatrics 200314236-40. n24
bottle-feeding infants
30
Feeding behavior in late preterm infants -
maturation in suck/swallow/breathing
Mizuno, Ueda. J Pediatrics 200314236-40.
31
Feeding issues for late preterm
babiesMaturation of suck - swallow - breathing

• Progressive improvement 35-37 wk.
• Mature swallowing _at_ 35 wk.
• Mature respiratory pattern during feeding _at_ 35-36
  wk.
• Full (nutritive) breastfeeding possible _at_ 36 wk.

32
Car safety seats respiratory instability

• AAP Observation in car seat for all infants lt
  37 wks
• 24 of near term babies do not fit securely
• O2 sats decline from 97 to 94 over 1 hr.
• Some have O2 sats lt 90 for 20 minutes
• 12 of near term babies have apnea
• bradycardia (in car seat)

Merchant et al. Pediatrics 2001108 647-652.
(n50 NT 50 T)
33
Jaundice in breastfed infants (two conditions)

• Breastfeeding jaundice Breast non-feeding
  jaundice
• Abnormal dysfunctional
• Within the first week of life
• Usually in primiparous or first time BF mothers
• Usually in near-term, or large preterm infants
• Breastmilk jaundice Breast milk jaundice
• Normal physiologic
• After the first week of life

34
Pattern of serum bilirubin in near term babies


TSB mg/dl
Days of age
Sarici et al, Pediatrics 2004113775. Turkey
nomogram n 196/365.
35
Risk factors for severe hyperbilirubinemia in
babies gt35 weeks.

• Pre-discharge bili (TSB or TcB) in high risk zone
• Jaundice in first 24 hrs.
• Blood group incompatibility, Coombs test, other
  hemolysis
• Gestational age 35-36 weeks
• Previous sibling with hyperbilirubinemia/photother
  apy
• Cephalohematoma or bruising
• Exclusive breastfeeding
• East Asian race
• Large weight loss after birth

Clinical Practice Guideline Management of
hyperbilirubinemia in the newborn infant 35 or
more weeks of gestation. AAP, Pediatrics
2004114297-316.
36
Risk nomogram for severe hyperbilirubinemia in
babies gt35 weeks.
37
Bilirubin toxicity

• Severe, unconjugated hyperbilirubinemia
• Bilirubin encephalopathy
• Kernicterus

38
Bilirubin encephalopathy

• Hypertonia
• Arching
• Retrocollis
• Opisthotonus
• Fever
• High-pitched cry

39
Pre-discharge and Readmission TSB in 18 Babies
with Kernicterus
95th ile 75th ile 40th ile 25th ile
40
Kernicterus in breastfed infants

• Near term babies are over-represented among
  kernicterus cases in national registry.
• RISK FACTORS
• Near-term babies
• Poor breastfeeding
• Poor follow-up
• Dehydration (excessive weight loss gt 10)
• Starvation
• Hyperbilirubinemia
• Maisels, MJ Pediatr 199596730
• Guidelines for Perinatal Care. AAP and ACOG.
  Fifth Edition, October 2002.

41
AAP Guideline Recommendations

• Promote support successful breastfeeding.
• Establish nursery protocols for eval of jaundice.
  
• Measure TSB or TcB in infants jaundiced in first
  24 hours.
• Visual estimation of jaundice leads to errors,
  especially in darkly pigmented infants.
• Interpret bili levels according to age in hours.
• Recognize infants lt 38 weeks gest, particularly
  those who are breastfed, as at higher risk
  require closer surveillance.

42
AAP Guideline Recommendations

• Perform systematic assessment on all infants
  before DC for risk of severe hyperbili.
• Provide parents with written verbal info about
  jaundice.
• Provide appropriate follow-up based on time of DC
  risk assessment.
• Treat newborns, when indicated, with phototherapy
  or exchange transfusion.
• Clinical Practice Guideline Management of
  hyperbilirubinemia in the newborn infant 35 or
  more weeks of gestation. AAP, Pediatrics
  2004114297-316.

43
Treatment options for jaundiced infants
Clinical Practice Guideline Management of
hyperbilirubinemia in the newborn infant 35 or
more weeks of gestation. AAP, Pediatrics
2004114297-316.
44
Monitoring treatment options for jaundiced
infants - practical points

• Do not supplement non-dehydrated breastfed
  infants with water or dextrose-water.
• Mothers should nurse 8 to 12 times per day for
  first few days.
• Protocols for assessing jaundice should include
  nursing staff obtaining TSB or TcB without MD
  order.
• Obtain pre-DC bili /- assess clinical risk
  factors.
• All infants seen in first few days after DC.
• Delay DC if appropriate F/U cannot be ensured.

45
Rehospitalization of newborn infants
5.3 - 9.6 for 33-37 weeks gestation 3.6 - 4.4
at 38-42 weeks gestation
Escobar Semin Perinatol 20063028.
46
Indications for readmission to hospital for
neonates within first two weeks

• Bilirubin gt 20 mg/dl
• Dehydration, Na gt 150 mEq/l
• Weight loss gt 10
• Poor breastfeeding
• Rule-out sepsis
• Apnea
• Seizures
• Maisels MJ, Kring E. Length of stay, jaundice
  hospital readmission. Pediatrics.
  1998101995-998.

47
Factors associated with readmission for late
preterm infants
Breastfeeding Jaundice in nursery Short hospital
stay (never in NICU) Asian race Diabetic
mother Teen mother Lower SES
Pediatrics 2004114708. Arch Dis Child
200590125. Arch Pediatr Adolesc Med
2002156155. Pediatrics 1998101995.
48
Factors associated with readmission for jaundice

• Prematurity 36-37 weeks gestation OR 7.7
• Prematurity lt 36 weeks gestation OR 13.2
• Breastfeeding OR 4.2
  
• LOS lt 48 hours
  OR 2.4
• Jaundice during initial nursery stay OR 7.8
• Male gender OR 2.9
• Maisels MJ, Kring E. Length of stay, jaundice
  and hospital readmission. Pediatrics.
  1998101995-998. n247/29,934 (0.8)

49
1 challenge
Supporting breastfeeding in the late preterm
infant
50
Pediatricians role in supporting breastfeeding
of the late preterm infant

• Support encourage breastfeeding
• Lead management team (RN, RD, IBCLC)
• Provide continuity of care
• Understand pump-induced lactation
• Skills to transition preterm infant to
  breastfeeding
• Oversee care of mother-infant dyad

Morton, JA The role of the pediatrician in
extended breastfeeding of the preterm infant.
Pediatric Annals, May 200332308-316.
51
Late preterm infant
Wight, N. Pediatric Annals 200332 329-336
52
Transitioning preterm/near term infant to
breastfeeding

• Challenges with positioning and latch
• proportionately larger head
• weak neck muscles
• smaller mouth in relationship to areola
• limited physical reserves
• propensity to fall asleep at breast from fatigue
  rather than satiety

53
Transitioning preterm/near term infant to
breastfeeding

• Physical assistance to latch
• Asymmetric latch more effective
• Contour breast to more easily fit into the babys
  mouth
• Silicone nipple shield may be needed
  (temporarily)
• Wight, N. Pediatric Annals 200332 329-336.
• Meier PP et al. Nipple shields for preterm
  infants. J Hum Lact 200016106-113.
• ABM Clinical protocols 3 10 at www.bfmed.org

54
Strategies to transition preterm infant to
breastfeeding

• Liberal supplementation
• 5 - 10 cc/feed day one
• 10 - 30 cc/feed after first day
• EBM gt pasteurized DBM gt elemental formula gt
  standard formula gt soy formula
• Ø glucose water
• Wight, N. Pediatric Annals 200332 329-336.
• ABM Clinical protocols 10 Breastfeeding the
  near-term infant
• 3 Hospital guidelines for supplementary
  feedings at www.bfmed.org

55
Strategies for supplementation of late preterm
infants

• Bottle feedings
• Gavage feedings
• Supplemental nursing systems
• Cup feedings
• Finger feedings
• Pumping goes with any of these

56
Strategies to transition late preterm infant to
full breastfeeding

• Extended rooming-in prior to DC
• Practical, individualized approach
• Mother uses pumping efforts of her infant
• Time-limited breastfeeding
• Liberal supplementation pumping
• with or without test weights
• Plan adjusted as progress made
• growth, strength stamina
• Morton, JA Pediatric Annals, May
  200332308-316.

57
Influence of bottle pacifier use ?

• Prevent successful breastfeeding
• Markers of breastfeeding difficulty
• Markers of decreased maternal motivation
• True cause of early weaning or associated with
  decline in breastfeeding?

58
Cup feedings - controversial strategy or
beneficial method ?

• Cup feedings safe and effective
• Cup feedings as good as, or better than, bottle
  feedings
• Preserve breastfeeding in preterm term infants
  who need multiple supplemental feeds.

Collins et al. Effects of bottles, cups
dummies on BF in preterm infants RCT Br Med
Journal 2004329193-198. n319. Howard et al.
RCT of pacifier use, bottle, cup feedings
effect on BF Pediatrics 2003111511-518.n700.
59
Minimum criteria for DC late preterm infants -
1.

• Feeding competency, temp stability no medical
  illness
• Not expected to meet competencies before 48
  hrs.
• MD directed medical care F/U visit 24-48 hrs
  after DC
• Stable VS x 12 hrs.
• At least one stool passed.
• 24 hrs of successful feeding, either breast or
  bottle
• No dehydration, if gt 2-3 wt. loss/day or gt 7
  of birth wt.
• Formal evaluation of BF position, latch, milk
  transfer x 2/day
• Feeding plan documented
• Risk assessment for severe hyperbilirubinemia
  F/U apt.
• PE wnl
• No bleeding x 2 hrs after circumcision

AAP COFN. Pediatr 2007120 1390.
60
Minimum criteria for DC late preterm infants -
2.

• All maternal infant labs done known
• HepB vaccine given or apt made
• Metabolic screening done F/U apt made
• Car safety seat study passed
• Hearing assessment documented
• Family, environmental social risk factors
  assessed
• Maternal competency documented for
• expected urine and stool output.
• cord care, hand hygiene
• thermometer use, clothing layers
• signs sx of illness, assessment of jaundice
• Safe sleep environment
• Safety issues, e.g. car seat, second hand smoke