Prematurity,
Neonatology, SIDS
Jay Green
Emergency Medicine Resident, PGY-2
July 19, 2007
Outline
Apparent Life-Threatening Events
 Sudden Infant Death Syndrome
 Other causes of apnea
 ±Quick snappers
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Won’t cover
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Fever/sepsis in the newborn
Bronchopulmonary dysplasia
Cerebral palsy
Obstructive hydrocehpalus
Case 1
5mo M, stopped breathing x ?1-2min
 Blue colour, limp
 Resolved before EMS arrived
 No vomiting, no sz activity
 Position - supine
 Noise - ?choking
 No abnormal eye mvts
 No intervention by parents
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Case 1 cont
OB Hx: no complications, SVD @ 38wks
 PMH: well child
 FHx
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– øApnea, øSIDS, øSz, øCHD
Case 1 cont
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O/E:
– Well-looking child
– Vitals
 HR 125, bp 85/55, RR 35, T 369
– Nothing remarkable to find
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Anything specific not to miss O/E?
– Fundoscopy, SpO2
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What is on your differential diagnosis?
Apparent Life-Threatening Event
ALTE
ALTE Definition

An episode that is frightening to the
observer and is characterized by some
combination of:
– Apnea
– Colour change
– Marked change in muscle tone
– Choking
– Gagging
National Institutes of Health Consensus Development
Conference on Infantile Apnea and Home Monitoring
ALTE Quick Stats
Incidence 0.5-6%
 4-8% of SIDS had a previous ALTE
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– Not considered same disease process
82% occur between 8am-8pm
 Usually < 6mo, avg 8-14wks
 Can be > 1yr
 13% risk of death if needed CPR and
discovered during sleep
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ALTE Hx/Exam
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Most NB parts of ED diagnostic evaluation
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History
– Colour, tone, resp effort
– Onset (sleep, feeding, awake), duration
– Position (prone, sitting, supine)
– Noises (stridor, choking)
– Eye movements
– Vomiting
– Intervention
ALTE - Exam
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PE usually normal
N = 73
 Dilated fundoscopic exam
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– Retinal hemorrhages in 1pt, child abuse in 4
Back to Case 1
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5mo M ?ALTE
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What would you like to do now?
– Labs?
– Imaging?
– Discharge patient?
ALTE Investigations
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50% have specific diagnosis found
– Infection, GI, Sz
ALTE Investigations
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196 infants with ALTE, mean age 2mo
83% hospital admission
50% had normal exam
25% had infection/fever
Diagnoses:
– Seizure (25%), GER (18%), febrile convulsion (12%),
LRTI (9%), apnea (9%)
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No infant subsequently died
65 infants with ALTE, mean age 7wks
 100% hospital admission (required)
 54% had normal exam
 Diagnoses:
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– GER (25%), unknown (23%), pertussis (9%),
Other LRTI (9%), Sz (9%), UTI (8%)
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No infant subsequently died
Thanks Yael!
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Investigation protocol
– 13% anemia, 33% ↑WBC (50% had inf)
– Metabolic screen, urine reducing substances,
ammonia not helpful
– ↓Bicarb in 20% - 7 dx with sepsis/sz
– ↑Lactate in 7, 5 had serious illness
– U/A, pertussis swab useful in 5% & 8%
– CXR abN in 9 who had N exam
Return to Case 1
Labs N
 CXR N
 ECG N
 Nasal swab, urine cultures pending
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What would you like to do now?
ALTE - Some Perspective
Pre-hospital study, retrospective
 N = 60, mean age 3.1mo
 83% no distress, 13% mild distress, 3%
moderate distress
 Diagnoses
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– Pneumonia (12%), sz (8%), sepsis (7%), ICH
(3%), bacterial meningitis (2%), anemia (2%)
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ALTE can be presenting sign of serious
illness, even in well-looking child Thanks Yael!
ALTE Disposition
Most studies recommend mandatory
period of inpatient observation
 Majority suffer only 1 event
 No single test has a high PPV for detecting
anything that will alter the outcome
 Recurrence rate for severe ALTE as high as
68% in one study
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– More likely in the few days after first event
ALTE Disposition
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If no cause for ALTE found
– Referred to as “apnea of infancy”
– ±home apnea-bradycardia monitoring
 Lack efficacy, frequent false alarms,
misinterpretation of alarm by parents
 Potential candidates
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Premature infants exhibiting apnea beyond term
Term infants with ALTE requiring resus
Siblings of 2+ SIDS victims
Infants with BPD/tracheostomies
ALTE Causes
Infection
 Seizure
 A/W Obstruction
 Breath-Holding Spells
 GER
 Metabolic
 Nonaccidental
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See EM Reports
Aug 7, 2006
ALTE  SIDS?
Prospective cohort study, N=141, 8yrs
 ?Association between SIDS & ALTE
 Conclusions
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– RF for all ALTE’s
 Common to SIDS: single parent, FHx infant death, smoking
during preg, marked night sweating
 Early behaviours: repeated apnea, cyanotic episodes, feeding
difficulties, marked pallor
– RF for “idiopathic ALTE”
 No common SIDS RF
– No subsequent SIDS deaths
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Conclusions
– ALTE/SIDS not part of the same disease
process
– SIDS prevention programs not expected to
lower ALTE frequency
ALTE Take-home Points
Scary + apnea, ∆colour, choking, ∆tone
 Usually < 6mo
 Well-looking ALTE  ?serious illness
 Inpatient work-up
 Not same disease process as SIDS
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Questions?
Case 2
4mo F, found blue, not breathing in crib
 EMS called, begin CPR, and patch in
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– Baby cyanotic, initial rhythm asystole, no resp
efforts
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What do you tell them?
– Continue CPR and come in?
– Call it in the field?
Sudden Infant Death Syndrome
Sudden death of an infant <1y old
 Remains unexplained after investigation:
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– Complete autopsy
– Examination of the death scene
– A review of the clinical history
National Institute of Child Health and Human Development
SIDS Fast Facts
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US data
– 0.72/1000 live births in 1998
– Declining incidence
– 3000 deaths/yr
95% < 6-8mo, peak 2-4mo
 1% < 1mo, 2% > 2yr
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What are some risk factors for SIDS?
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Maternal
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Smoking
Drug use
↓SES
Age<20 at G1
Ethnicity
↓Education
No prenatal care
Prenatal
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IUGR
Multiples
Prematuriy
BW < 2500g
What is the most important modifiable risk factor?
Prone sleeping 78%17%, SIDS ↓ 40%!
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Postnatal
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Prone sleeping
ETS
Warm temp
Loose bedding
Soft surface
Bed sharing
?infection
?GER
?arrhythmia
SIDS – What Happens?
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>70 theories: “triple-risk theory” – Rosen’s
Predisposing factors
Sleep
Immature Physiologic
cardiorespiratory
stuff control
Autonomic dysfunction
↓ baroreceptor reflex
↓vasomotor
Is sleep evercontrol
bad…I guess so…
↓central venous return, CO, bp
Prone sleep
Exacerbate these effects
URTI
Progressive
Various badness
bradycardia
that doesn’t help
Overheating
Poor lung perfusion  hypoxia
SIDS
Case 2 cont
4mo F just arrived in your ED
 CPR continuing
 Pupils fixed mid-dilated
 Rhythm asystole
 Unknown downtime
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How long do you continue the resus?
– ~3 rounds of drugs
SIDS Outcome
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After infant declared dead
– Blood, urine, skin samples
– Family meeting
– Coroner notified
 House inspection
 Autopsy
SIDS Pathologically Speaking
Nothing pathognomonic
 Some typical findings
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– PA smooth muscle hypertrophy
– RVH
– ↑ hepatic hematopoiesis
– ↑ periadrenal brown fat
– Adrenal medullary hyperplasia
– Carotid body abnormalities
– Brainstem gliosis
SIDS Effects
Guilt, blaming, social alienation
 ↑ miscarriage rate, divorce, infertility
 Potentially helpful steps:
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– Openly accepting grief reactions
– Allowing family to vocalize their feelings
– Clarifying misconceptions
– Allowing the family to hold/be along with infant
– Private place for family to gather
– Explanation of cause of death
Case 2 cont
Unsuccessful resuscitation
 Infant declared dead
 Parents inform you that infant has a twin
brother
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What should you do about this?
– Inform them there’s no increased risk?
– Admit the twin for observation?
SIDS - Twins
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Cohort studies looking at twins
– Variable findings, 2x increased risk of SIDS
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Any sibling of SIDS victims
– 5-6x increased risk of SIDS
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Reasonable to admit the twin for a period
of observation
SIDS Prevention
Non-prone sleeping (supine preferred)
 No sleeping in waterbeds, sofas, soft
mattresses/surfaces
 No soft materials in sleeping env’t
 Avoid bed-sharing and co-sleeping
 Avoid overheating
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Retrospective review, 10yrs  ?↑ risk with ↑ time
 All deaths < 1yr in Quebec  ?↑ risk with position
 No ↑ risk with
 396 SIDS deaths
premature infants
 Infants <1mo
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– 10.2% died sitting
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Infants >1mo
– 1.4% died sitting
– P<0.001
– RR 7.35
Conclusions:
-an excess of infants <1mo died
in sitting position compared to
those >1mo
-length of time in seat and
position may be NB contributors
SIDS Take-home points
Peak age 2-4mo
 Prone sleeping most NB modifiable RF
 SIDS death can be called in the field
 Resus of asystolic neonate x ~3 rounds
 Admit twin of SIDS victim
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Questions?
Apnea Definitions
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Pathological apnea
– Respiratory pause > 20sec or assoc with cyanosis,
pallor, hypotonia, bradycardia
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Apnea of prematurity
– Periodic breathing with pathological apnea
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Apnea of infancy
– Infant > 37wks, pathological apnea or shorter apneic
pauses & bradycardia, cyanosis, pallor, or hypotonia
– “Idiopathic ALTE”
Case 3
10d F breathing pauses lasting ~5s
 4-5 episodes/min, comes & goes
 Born at 39wks
 Uncomplicated preg/delivery to G1P1
 No fever, rash, lethargy
 Feeding well
 10-12 wet diapers/d, 3-4 seedy stools/d
 Regained birthweight at 7d
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Case 3
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O/E
– VS N
– Well looking child, no apneic episodes in ED
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What next?
– Labs?
– Imaging?
– Discharge?
– What do you think is going on?
Periodic Breathing
Normal
 3 or more pauses of >3sec with less than
20sec of N respirations between pauses
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Treatment?
– Caffeine
Methylxanthines
Helpful in apnea of prematurity and in
reducing periodic breathing
 Caffeine better than theophylline
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– Longer half-life
– Wider therapeutic index
– More reliable absorption
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Caffeine citrate 20mg/kg IV/PO load
– 5-8mg/kg OD
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Why do we use caffeine?
Caffeine – Mechanism of Action
Increases levels of 3’5’-cyclic AMP by inhibiting
phosphodiesterase
 CNS stimulant
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– Increases medullary resp center sensitivity to CO2
Stimulates central inspiratory drive
 Improves skeletal muscle contraction
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– Diaphragmatic contractility
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Prevention of apnea may occur by competitive
inhibition of adenosine
Caffeine
N=15 with periodic breathing (PB)
 Conclusions
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– Weak correlation btw GER and PB
– Theophylline/caffeine
 Marked reduction of PB
 Increases GER
Skopnik H et al. Effect of methylxanthines on periodic respiration and acid gastroesophageal reflux in newborn infants. Monatsschrift Kinderheilkunde 1990;138(3):123-7
Case 4
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4d M apneic episodes today lasting ~30s
– ?A bit blue during episodes
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Discharged from hospital today
Infant born @ 361 wks
Uncomplicated preg/delivery
O/E
– VS N, well child, no apneic episodes in ED
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Investigations?
Disposition?
What does this child have?
Apnea of Prematurity
Periodic breathing with apneic episodes >
20sec
 Usually resolves by 37wks gestation
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Management?
– Inpatient work-up/monitoring
– Caffeine citrate 20mg/kg IV/PO load
 5-8mg/kg OD
Apnea Take-home Points
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Periodic breathing is normal
– 3+ pauses >3sec with <20sec of N resps btw
Caffeine helps in periodic breathing and
apnea of prematurity
 Pathological apnea is >20sec
 Pathological apnea always deserves W/U
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Questions?
Quick Snapper #1
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5d M poor feeding & vomiting x 1d
D/C yesterday
Born 361, difficult labour, decels, forceps
Breast-fed, with bottle supplementation
Gaining weight x 2d
No bloody stools, non-bilious emesis, no fever
O/E
– Vitals N
– Abdo ?distended
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Investigations?
Quick Snapper #1
Necrotizing Enterocolitis (NEC)
Mucosal/transmural intestinal necrosis
 Most common GI emergency, but often
presents prior to d/c
 90% premature
 >32wks usually present in 1st week of life
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– Can be >3mo in VLBW infants
NEC Pathogenesis
Unknown
 Probably combination of
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– Mucosal injury (ischemia, infection,
inflammation)
– Host's response to injury (circulatory,
immunologic, inflammatory)
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RF
– Aggressive enteral feeding, birth-related
hypoxic-ischemic insults, infection
NEC
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Radiological appearance
– Dilated loops
– Pneumatosis intestinalis (present in 75%)
– Biliary tract air
– Pneumatosis gastralis
– Free air (only present in 50-75% with perf)
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Labs not diagnostic
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Treatment?
NEC Management
Consult peds surgery
 Admission
 NPO
 NG/OG
 Careful fluid/lyte mgmt (3rd spacing)
 ±Abx (amp/gent/flagyl)
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NEC Take-home Points
90% are premature
 Usually early but can be >3mo in VLBW
 Pneumatosis intestinalis specific for NEC
 Admit, NPO, Fluids, NG, ±Abx, ±Surgery
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Questions?
Quick Snapper #2
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6d F “off-colour” x 1-2 days - ?jaundice
Born 386, uncomplicated delivery via C/S
Feeding well, 10 wet diapers, 3 stool/d
Wt – regained birth weight today
No fever, lethargy, irritability
FHx: nothing metabolic/congenital
O/E
– Well-looking child, VS N
– Slight jaundice
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Investigations?
Quick Snapper #2
CBC N
 Total bili = 200μmol/L
 Conjugated bili not elevated
 U/A –ve
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What now?
Jaundice
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Indications for further work-up?
– Jaundice appearing <24h after birth
– Elevated conjugated bili
– Rapidly rising total serum bilirubin
– Total serum bilirubin approaching exchange
level or not responding to phototherapy
– Jaundice persisting beyond age 3 weeks
– Sick-appearing infant
Rosen’s
Neonatal Jaundice
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HUGE differential
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What does this infant have?
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Physiological jaundice
– 60% incidence 1st week of life
– Gradual bili increase until 3rd day of life
– Bili returns to N ~2wks
– Why does this happen?
Quick Snapper #2
6d F
 Jaundice, otherwise well-looking
 Bili 200
 Urine -ve
 ?Physiologic jaundice
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Management?
Neonatal Jaundice Management
Continue breastfeeding
 Monitoring
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– Homecare, FP
±Phototherapy
 ±Exchange transfusions
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Complications?
– Neurotoxicity, encephalopathy, kernicterus
Neonatal Jaundice Take-home Points
60% will get physiologic jaundice
 Conjugated hyperbili is pathological
 Jaundice in first 24h of life is pathological
 Know indications for further W/U
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The End
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Questions?