Transcript Update in care of the preterm infant

Update: “Late preterm infants –
a population at risk”
Susan Landers MD, FAAP, FABM
Pediatrix Medical Group
Seton Medical Center & Dell Children’s
Medical Center of Central Texas
Austin, TX
Preterm births in Texas: 1994-2004
National Center for Health Statistics, final natality data
Retrieved 12/03/2007 from www.marchofdimes.com/peristats.
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.
Preterm births in
US: 2004
National Center for Health
Statistics, final natality data
Retrieved 12/03/2007 from
www.marchofdimes.com/peristats.
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
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
Golden Rule
Late preterm infants are not
term babies.
If you expect them to act like
term babies, you will be
disappointed.
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
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
Davidoff et al. Semin Perinatol 2006; 30:9
2002 Infant Mortality Rates in US
per 1,000 live births
Martin et al. Births: final data for 2003. Nat Vital Stat Rep. 2005;54(2):1-116.
Higher rates of mortality
Late preterm infants, compared to term infants:




Early neonatal deaths (0-6 days)
Late neonatal deaths (7-28 days)
Post-neonatal deaths (>28 days)
Total infant mortality (0-1 year)
RR 5.2
RR 2.9
RR 2.0
RR 2.5
Causes of death:

Congenital anomalies, infections, asphyxia-related
disorders, respiratory failure, SIDS & external trauma
Kramer, et al JAMA 2000;284:843. Canadian & US births from 1985
& 1995. (n = US singletons 3,866,513 + Canada 726,435)
Clinical outcomes in near term babies
60
50
term
near term
40
%
30
20
10
0
temp
low glucose IV needed
instability
RDS
jaundice
Wang et al, Pediatrics 2004;114:372-376. Mass. Gen. Hosp. n=245.
Late preterm babies – respiratory morbidity
35
all resp disorders
30
RDS
TTN
25
20
%
15
10
Am J Ob Gyn 1992;166: 1629-45.
Am J Ob Gyn 1996;174:525-28.
5
Biol Neonate 1998;74:7-15.
0
34 wk
35 wk
36 wk
37 wk
38 wk
39 wk
European J Ob Gyn 2001;98:9-13.
Late preterm babies – morbidity in those with
early respiratory distress









Suspected sepsis
Antibiotic Rx > 7 days
Apnea, bradycardia, desaturation
Hypothermia, temp instability
Hypoglycemia
Feeding difficulties
NG or OG feedings
Phototherapy
NICU stay (days)
27%
33%
30%
98%
18%
27%
45%
57%
10
Am J Obstet Gynecol 2003:189:1053. Case Western, n=150
Late preterm babies – morbidities
in those without respiratory distress









Suspected sepsis
Antibiotic Rx > 7 days
Apnea, bradycardia, desaturation
Hypothermia, temp instability
Hypoglycemia
Feeding difficulties
NG or OG feedings
Phototherapy
NICU stay (days)
Am J Obstet Gynecol 2003:189:1053-1057.
3%
7%
5%
57%
9%
35%
21%
30%
7
Late preterm infants & complications of prematurity
during birth hospitalization
Outcome during
initial birth hosp.
Late preterm
morbidity
Term morbidity
OR (95% CI)
Feeding difficulties
32.2%
7.4%
Hypoglycemia
15.6%
5.3%
3.3 (1.1-12.2)
Jaundice
54.4%
37.9%
1.95 (1.04-3.67)
Temp. instability
10%
0
Apnea
4-12%
0
12 (4.5-24.3)
Respiratory distress
3.6-29%
0.6-4.2%
9.2 (2.9-37.8)
IV infusion
26.7%
5.3%
6.5 (2.3-22.9)
Sepsis evaluation
36.7%
12.6%
4 (1.8-9.2)
Mech ventilation
3.4%
0.9%
Engle, Tomashek, Wallman & COFN. AAP Clinical Report. Pediatr 2007;120:1390-1401.
Neutral thermal environment
 Body temperature at which baby’s oxygen
consumption is minimized
 Heat loss/heat transfer
 Radiant
 Conductive
 Evaporative
 Convective
 Nonshivering chemical thermogenesis
 Brown fat regulates
 Consumes O2 and glucose
↑ 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
Neutral thermal environment

Hypothermia < 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.
Infants at risk for hypoglycemia
Incidence
LBW & preterm
 SGA
 LGA
 IUGR
 IDM
 Perinatal stress

15 - 20 %
20 - 30 %
8 - 10 %
20 %
10 - 30 %
5 - 10%
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

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
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
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 @ www.bfmed.org
Breastfeeding Med. 2006; 1(3): 178-184.
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
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-swallowbreathing pattern

Feeding behavior in late preterm infants maturation in sucking variables
80
60
40
20
0
sucking press (mmHg)
sucking freq (min)
-20
-40
-60
-80
-100
32 wk
33 wk
34 wk
35 wk
36 wk
Mizuno, Ueda. J Pediatrics 2003;142:36-40. n=24 bottle-feeding infants
Feeding behavior in late preterm infants maturation in sucking variables
12
10
8
sucking duration (sec)
6
sucking efficiency
(ml/min)
4
2
0
32 wk
33 wk
34 wk
35 wk
36 wk
Mizuno, Ueda. J Pediatrics 2003;142:36-40. n=24 bottle-feeding infants
Feeding behavior in late preterm infants maturation in suck/swallow/breathing
Mizuno, Ueda. J Pediatrics 2003;142:36-40.
Feeding issues for late preterm babies:
Maturation of suck - swallow - breathing
 Progressive improvement 35-37 wk.
 Mature swallowing @ 35 wk.
 Mature respiratory pattern during feeding @
35-36 wk.
 Full (nutritive) breastfeeding possible @ 36
wk.
Car safety seats & respiratory instability
 AAP: “Observation in car seat for all infants < 37 wks”
 24% of near term babies do not fit securely
 O2 sat’s decline from 97% to 94% over 1 hr.
 Some have O2 sat’s < 90% for 20 minutes
 12% of near term babies have apnea
& bradycardia (in car seat)
Merchant et al. Pediatrics 2001;108:
647-652. (n=50 NT + 50 T)
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
Pattern of serum bilirubin
in near term babies
14
*
*
12
10
TSB
mg/dl
8
term
near term
6
4
2
0
1
2
3
4
Days of age
5
7
Sarici et al, Pediatrics 2004;113:775. Turkey “nomogram” n= 196/365.
Risk factors for severe hyperbilirubinemia
in babies >35 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/phototherapy
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 2004;114:297-316.
Risk nomogram for severe hyperbilirubinemia
in babies >35 weeks.
Bilirubin toxicity



Severe, unconjugated hyperbilirubinemia
Bilirubin encephalopathy
Kernicterus
Bilirubin encephalopathy
Hypertonia
 Arching
 Retrocollis
 Opisthotonus
 Fever
 High-pitched cry

Pre-discharge and Readmission TSB in 18
Babies with Kernicterus
Total Serum Bilirubin (mg/dl)
50
40
30
20
95th %ile
75th %ile
40th %ile
25th %ile
10
0
Age 12 24 36 48 60 72 84 96 108 120 132 144 156 168 hrs
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 > 10%)
 Starvation
 Hyperbilirubinemia
Maisels, MJ Pediatr 1995;96:730
Guidelines for Perinatal Care. AAP and ACOG. Fifth Edition, October 2002.
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 < 38 weeks gest, particularly
those who are breastfed, as at higher risk &
require closer surveillance.

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 2004;114:297-316.
Treatment options for jaundiced infants
“Clinical Practice Guideline : Management of hyperbilirubinemia in the newborn infant
35 or more weeks of gestation.” AAP, Pediatrics 2004;114:297-316.
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.
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 2006;30:28.
Indications for readmission to hospital
for neonates within first two weeks
 Bilirubin > 20 mg/dl
 Dehydration, Na > 150 mEq/l
 Weight loss > 10%
 Poor breastfeeding
 Rule-out sepsis
 Apnea
 Seizures
Maisels MJ, Kring E. “Length of stay, jaundice & hospital
readmission.” Pediatrics. 1998;101:995-998.
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 2004;114:708.
Arch Dis Child 2005;90:125.
Arch Pediatr Adolesc Med
2002;156:155.
Pediatrics 1998;101:995.
Factors associated with
readmission for jaundice






Prematurity 36-37 weeks gestation
Prematurity < 36 weeks gestation
Breastfeeding
LOS < 48 hours
Jaundice during initial nursery stay
Male gender
OR 7.7
OR 13.2
OR 4.2
OR 2.4
OR 7.8
OR 2.9
Maisels MJ, Kring E. “Length of stay, jaundice and hospital readmission.” Pediatrics.
1998;101:995-998. n=247/29,934 (0.8%)
# 1 challenge
Pediatrician’s 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 2003;32:308-316.
insufficient
breast stimulation,
incomplete
emptying
less stamina
less coordinated suck/swallow
less effective sucking
less alert / awake periods
Late preterm
infant
insufficient milk supply
insufficient milk transfer
Hypoglycemia
Jaundice
Poor weight gain
Readmission
Wight, N. Pediatric Annals 2003:32: 329-336
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

Transitioning preterm/near term infant
to breastfeeding




Physical assistance to latch
Asymmetric latch more effective
Contour breast to more easily fit into the baby’s mouth
Silicone nipple shield may be needed (temporarily)
Wight, N. Pediatric Annals 2003:32: 329-336.
Meier PP et al. Nipple shields for preterm infants. J Hum Lact
2000;16:106-113.
ABM Clinical protocols 3 &10 at www.bfmed.org
Strategies to transition preterm infant
to breastfeeding

Liberal supplementation
5 - 10 cc/feed day one
 10 - 30 cc/feed after first day
 EBM > pasteurized DBM > elemental formula >
standard formula > soy formula
 Ø glucose water

Wight, N. Pediatric Annals 2003:32: 329-336.
ABM Clinical protocols #10 “Breastfeeding the near-term infant” &
#3 “Hospital guidelines for supplementary feedings” at www.bfmed.org
Strategies for supplementation
of late preterm infants
1)
2)
3)
4)
5)
6)
Bottle feedings
Gavage feedings
Supplemental nursing systems
Cup feedings
Finger feedings
Pumping goes with any of these
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 2003;32:308-316.
Influence of bottle & pacifier use ?
1) Prevent successful breastfeeding
2) Markers of breastfeeding difficulty
3) Markers of decreased maternal motivation
4) True cause of early weaning or associated
with decline in breastfeeding?
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 2004;329;193-198. n=319.
Howard et al. “RCT of pacifier use, bottle, cup feedings & effect on BF…” Pediatrics
2003;111:511-518.n=700.
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 > 2-3% wt. loss/day or > 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 2007;120: 1390.
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