Transcript Neonatology compressed

LMCC Review Course
“Neonatology”
Brigitte Lemyre, MD, FRCPC
Outline
Resuscitation principles, transition to
life
 Normal newborn care and assessment
 IUGR and LGA and their problems
 Prematurity and its complications
 Problems of the term infant
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Infant mortality:
9-10: 1000 births
Due to congenital anomalies, prematurity,
asphyxia, infections, SIDS
Normal baby at term:
HR: 120-160/min
RR: 40-60/min
Weight: 2.5-4.5 kg
BP: 50-80/30-40 mmHg
Gestational age and size
Gestation
28 weeks
30 weeks
33 weeks
35 weeks
37-40 weeks
Size
1.0 kg
1.5 kg
2.0 kg
2.3 kg
2.5 – 4.5 kg
Newborn Resuscitation
Initial steps
 Evaluate respiration
 Evaluate heart rate
 Evaluate color
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Remember - the usual problem in
the neonate is the lungs:
VENTILATION!
Fluid filled alveoli in utero
Diminished blood flow through fetal lungs
Importance of first
breath
Newborn Resuscitation
A: Airway
 B: Breathing
 C: Circulation
 D: Drugs
 E: Environment
 F: Fluids
 G: Glucose
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Special Circumstances in
Newborn Resuscitation
Meconium in amniotic fluid AND
depressed newborn (not crying, limp):
Intubate and suction below cords
 Suspect diaphragmatic hernia:
Intubate
 Pink when crying, blue when not:
Suspect choanal atresia and try an
oral airway
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The Apgar Score
Feature
0 points
1 point
2 points
Heart rate
Respiratory
Effort
0
Apnea
< 100
Irregular,
gasping
> 100
Regular,
crying
Color
Pale, blue
Pale or blue
extremities
Pink
Muscle tone Absent
Reflex
irritability
Absent
Weak,
Active
passive tone movement
Grimace
Active
avoidance
Principles of Routine Care
Ensure warmth and adequate nutrient
intake
 Monitor weight, hydration status
 Support breastfeeding
 Educate about infant care
 Anticipatory guidance
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Principles of Routine Care
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Prophylaxis for common problems
– Eye care: erythromycin ointment
– Vitamin K: 1 mg IM
Screening for disease: >24h
– PKU (1/15,000)
– Hypothyroidism (1/4000)
– Neurosensory hearing loss
– 24 other metabolic diseases (organic acid
disorders, FAOD, aminoacid disorders, sickle
cell and hemoglobinopathies, CAH, galactosemia,
endocrinopathies)
Blood group and Coombs if mother rH neg
The depressed newborn
Asphyxia
 Respiratory condition
 Hypovolemia/shock
 Drugs
 CNS Trauma
 Congenital malformations
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Perinatal Asphyxia
Must be documented by cordocentesis, fetal
scalp blood sampling, cord blood sampling
 pH < 7.00, base deficit > 15 mEq/L
 Encephalopathy
 Multiorgan involvement (heart, kidneys,
marrow, liver)
For perinatal asphyxia to have been cause of
later neurodevelopmental problem, must
document neonatal encephalopathy
The Newborn History
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The baby’s history is:
– the family history
– the mother’s past medical history
– the mother’s pregnancy history
(including any information about
screening tests, amniotic fluid)
– the labor and delivery history (including
the placenta and umbilical cord)
– the resuscitation history
Physical Examination
Vital signs
 Measurements: plot on curves
 Gestational age assessment
 Overall appearance
 System by system
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Most common anomalies
noted on initial exam
Skin tags
Polydactyly
10-15/1000
10-15/1000
Cleft lip or palate
Congenital heart defect
1-4/1000
1-4/1000
Congenital hip dysplasia
1-4/1000
Down Syndrome
1-4/1000
Talipes equinovarus
1-4/1000
Spina bifida
1-4/10,000
Most frequent birth injuries
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Asphyxia
Broken clavicle
Facial palsy
Brachial plexus injury
Fractures of humerus or skull
Lacerations or scalp injuries
Ruptured internal organs
Testicular trauma
Fat necrosis
Commonest Congenital
Abdominal Masses
Renal (55%)
 Genital (15%)
 Gastrointestinal (15%)
 Liver and Biliary (5%)
 Retroperitoneal (5%)
 Adrenal (5%)
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Common physical findings of
clinical significance
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Apnea, tachypnea, grunting
Bradycardia, cyanosis
Hypotonia
Absent or decreased femoral pulses
Heart murmur
Organomegaly
Absent red reflex
Jaundice
Plethora or pallor or diffuse petechiae
Disorders of gestation
length or of growth
Small for gestational age: <2SD below
 Large for gestational age: >2SD above
 Prematurity: <37 weeks gestation
 Postmaturity: >42 weeks gestation
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Small for gestational age:
etiologies
Constitutional: ethnicity
 Maternal: illness, Rx/R-OH/drugs,
nutrition
 Placental
 Fetal: genetic disorder, infections
(TORCH)
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Small for gestational age:
complications
Asphyxia
 Meconium aspiration
 Congenital malformations
 Hypoglycemia
 Hypothermia
 Hypocalcemia
 Polycythemia-hyperviscosity
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Small for gestational age:
Management
Optimal resuscitation
 Maintenance of body temperature
 Early feeds or administration of
glucose
 Meticulous history and physical
examination, including placenta
 Work-up for etiology
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Disorders of gestation
length or of growth
Small for gestational age: <2SD below
 Large for gestational age: >2SD above
 Prematurity: <37 weeks gestation
 Postmaturity: >42 weeks gestation
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Large for gestational age:
Etiologies
Constitutional
 Abnormal maternal glucose tolerance
 Syndromes: Beckwith-Wiedemann
Sotos
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Large for gestational age:
Complications
Asphyxia
 Birth trauma
 Hypoglycemia
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Large for gestational age:
Management
Optimal resuscitation
 Early feeds or administration of
glucose
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Disorders of gestation
length or of growth
Small for gestational age: <2SD below
 Large for gestational age: >2SD above
 Prematurity: <37 weeks gestation
 Postmaturity: >42 weeks gestation
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Risk Factors for Prematurity
-previous preterm birth/labour
-cervical/placental anomalies
-chorioamnionitis
-uterine distention
-twins/multiple pregnancy
-maternal medical conditions
-low pre-pregnancy weight
-maternal age
Risk Factors for Prematurity
–cigarette smoking
–high perceived stress
–bacterial vaginoses
–cocaine use
–urinary tract infection
–asymptomatic bacteriuria
Prematurity: Complications
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Respiratory distress syndrome
Bronchopulmonary dysplasia
Apnea of prematurity
Patent ductus arteriosus
Intraventricular hemorrhage
Periventricular leukomalacia
Necrotizing enterocolitis
Sepsis
Anemia
Retinopathy of prematurity
Respiratory Distress
Syndrome
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Etiology
– Anatomic immaturity of the lung
– Increased interstitial and alveolar lung
fluid
– Surfactant deficiency
Management
– Prevention: antenatal steroids
– Oxygen
– Positive pressure
– Surfactant
17
Weeks
Courtesy of Professor Louis De Vos
http://www.ulb.ac.be/sciences/biodic/index.html
22
Weeks
Courtesy of Professor Louis De Vos
http://www.ulb.ac.be/sciences/biodic/index.html
25
Weeks
Courtesy of Professor Louis De Vos
http://www.ulb.ac.be/sciences/biodic/index.html
Bronchopulmonary Dysplasia
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Respiratory symptoms, oxygen requirement
for at least 28 days, and X-ray abnormalities
at 36 wks postconceptional age
Pathophysiology: disturbed alveolarization
-Lung inflammation
-Mucociliary dysfunction
-Airway narrowing
-Hypertrophied airway smooth muscle
-Alveolar collapse
-Constriction of pulmonary vascular bed
Bronchopulmonary Dysplasia
Management:
–Prevention
–Nutrition
–Oxygen +/- ventilation
–Bronchodilators
–Diuretics
–Steroids: inhaled vs systemic
Apnea of Prematurity
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Central, obstructive, or mixed
Majority of <32 weeks
Treat with
– Adequate positioning
– Oxygen
– Methylxanthines
– CPAP
– Ventilation if necessary
Patent ductus arteriosus
Up to 42% of < 1500 g babies
 Management strategies:
-preload/afterload reduction
-Adequate oxygenation
-Optimize pH
-indomethacin
-surgery
-conservative management
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Metabolic Problems of
Prematurity
Hypoglycemia
 Fluid/electrolyte imbalance
 Hypocalcemia/hypomagnesemia
 Hyperbilirubinemia
 Hypothermia
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Intraventricular hemorrhage
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Common in < 1500 gm babies
Usually evident in 1st week of life
Reasons:
– highly vascularized germinal matrix
– less basement membrane to capillaries
– abnormal autoregulation
Prognosis good for small amount bleeding in
ventricles but poorer if large amount
intraparenchymally or if posthemorrhagic
hydrocephalus
Periventricular leukomalacia
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Ischemic lesion to watershed area around
ventricles in premature infants
Link to inflammation?
Most often shows up 3-4 wks after
delivery
Correlated with cerebral palsy
Necrotizing Enterocolitis
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1-5% NICU admissions
Multifactorial etiology
feeds, prematurity, ischemia, infection
Diagnosis: clinical and radiologic
Treatment:
– Decompression (NPO, NG tube)
– antibiotics
– surgery if necessary
Sepsis
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Suboptimal immune function in preemies plus
poor skin barrier, indwelling catheters
GBS and coliforms cause early onset sepsis
< 5-7 days of life
Nosocomial sepsis common in prems with most
common organism = coagulase negative
staphylococcus; fungi can also be problematic
in > 1 week of life
Anemia of Prematurity
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Reasons:
– decreased hemoglobin at delivery
– decreased RBC survival
– blunted erythropoietin response
– IATROGENIC
Treatment:
– prevention
– iron supplementation
– transfusion
– EPO
Retinopathy of Prematurity
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40-70% NICU survivors < 1000 g
Etiology: vasoconstriction leading to
abnormal vascular proliferation
Diagnosis: screening
Treatment: close monitoring, laser if
necessary
Disorders of gestation
length or of growth
Small for gestational age: <2SD below
 Large for gestational age: >2SD above
 Prematurity: <37 weeks gestation
 Postmaturity: >42 weeks gestation
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Postmaturity
Labour tends to be induced to avoid
problems of postmaturity, however if
dates not accurate may still occur
 Possible complications
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– growth disturbances
– asphyxia
– meconium aspiration syndrome
Problems of the Term
Newborn
Respiratory
 Cardiac
 Sepsis
 Digestive
 Jaundice
 Anemia, polycythemia, hemorrhage
 Renal
 Endocrine
 Neurologic
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Respiratory Distress in the
Newborn
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Respiratory system
Cardiac
Infectious
Neurologic
Metabolic
Upper airway
Maternal Rx
Musculoskeletal
Respiratory Problems in the
Term Newborn
Transient tachypnea of the newborn
 Pneumonia
 Meconium aspiration
 Pulmonary air leaks
 Congenital malformations
 Persistent pulmonary hypertension
 Pulmonary hemorrhage
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Transient Tachypnea of the
Newborn
Failure to clear lung fluid
 Associated with absent or short
labour or initial weak or absent
respirations
 Improves with time
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Pneumonia
Can initially be difficult to distinguish
from TTN/RDS
 Group B Strep #1
 Consolidation may appear after a few
days
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Meconium Aspiration
Syndrome
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Meconium-stained amniotic fluid
Intrauterine insult may lead to gasping
Meconium aspirated
– Pneumonitis
– Airway occlusion
– Pulmonary air leak syndrome
May lead to persistent pulmonary
hypertension
Congenital Malformations
Anomalies anywhere along airways,
extrinsic or intrinsic
 Atresias
 Cysts
 Diaphragmatic hernia
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Persistent Pulmonary
Hypertension
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Associated with
– asphyxia
– meconium aspiration
– sepsis
Right to left shunting, persistent fetal
circulation
Treatment:
– oxygenation, ventilation
– maintain blood pressure
– pulmonary vasodilators
Congenital Heart Disease:
presentations
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Cyanosis
– presents early
– defects with right to left shunts
– TOF, tricuspic atresia, TGA, TAPVR,
truncus arteriosus, pulm. atresia
Congestive heart failure
– fewer compensatory mechanisms so
common and can occur very quickly
– tachycardia, tachypnea, hepatomegaly,
feeding difficulty, cardiomegaly,
diaphoresis
Presentations of Congenital
Heart Disease
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Murmurs
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Dysrhythmias
Congenital heart disease:
Most commonly diagnosed
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Ventricular Septal Defect
Transposition of the Great Vessels
Tetralogy of Fallot
Coarctation of the Aorta
Patent Ductus Arteriosus
Endocardial Cushion Defect
Hypoplastic Left Heart
Sepsis: risk factors
Preterm rupture of membranes
 Prolonged rupture of membranes
 Maternal group B strep carriage
 Chorioamnionitis
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Neonatal Sepsis
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THINK OF IT!
– Signs may be subtle, non-specific
– Incidence bacterial sepsis = 1-5/1000 live
births
– Commonest organisms:
 group B streptococcus
 gram negatives (E coli, Klebsiella)
 enterococcus, H flu, staph species
 listeria
Work up and treat if suspect sepsis
– Use broad spectrum antibiotics
Ophthalmia neonatorum
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1st days - differentiate chemical vs infected
2nd-3rd wk - viral or bacterial
Gonococcal:
– within 5 days of birth
– gram negative intracellular diplococci
– if suspect, Penicillin asap
– highly contagious
Chlamydia:
– 5-14 days
– conjunctival scraping
– topical antibiotics
Congenital Infections
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CMV:
– 5-25/1,000 live births
– asymptomatic vs severe symptoms
– microcephaly, thrombocytopenia,
hepatosplenomegaly, chorioretinitis
– sequelae of hearing loss and developmental
delay
Rubella
– 0.5/1,000
– cataracts, rash, congenital heart disease,
developmental delay
Congenital Infections
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Toxoplasmosis:
– 0.5-1.0/1,000
– hydrocephalus, cranial calcifications,
chorioretinitis
Syphilis:
– 0.1/1,000
– snuffles, osteochondritis/periostitis,
rash
Herpes:
– vesicles, keratoconjuntivitis, CNS
findings
Congenital syphilis
Treat mother no matter what stage
of pregnancy
 If adequate maternal treatment and
no signs of infection in newborn, give
one dose IM penicillin
 If inadequate maternal treatment,
give 10 days of IV penicillin
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Neonatal herpes simplex
Only about 1/3 mothers have overt
signs
 Infection can be disseminated or
local
 Usually present at 5-10 days of age
 If suspect:
– Cultures, PCR
– Treat with acylovir
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Maternal hepatitis B carrier
Give baby hepatitis vaccine as soon as
possible after birth (first 12 hours)
 Bath
 Universal precautions
 Immune globulin in first 7 days
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HIV
Virus can be transmitted
transplacentally, intrapartum, or
postpartum
 Screen mothers
 Treat mothers with antiretrovirals
 Treat babies with AZT for 6 wks
 Universal precautions
 Look for other infections (HepB,
HepC)
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Digestive Disorders
Vomiting
 Diarrhea
 Constipation
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Vomiting in the Newborn
Not uncommon for some vomiting in
1st few hours after birth
 Overfeeding, poor burping
 DDx: Gastrointestinal obstruction
Increased intracranial pressure
 Bilious vomiting is a medical
emergency!
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Upper G-I problems causing
vomiting
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Esophageal:
– first feed, soon after feed
– excessive drooling
– if T-E fistula, risk aspiration
Small bowel atresias
Malrotation and volvulus Need to r/o
Achalasia
Chalasia/GER
Pyloric stenosis
}
Non-GI causes of vomiting
Sepsis
 Adrenal hyperplasia
 Meningitis
 UTI
 Milk allergy
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Lower GI Obstruction
Initially, distention, failure to pass
meconium… vomiting is later sign
 Extrinsic vs intrinsic obstruction
 DDx: Imperforate anus, Hirschprung,
meconium ileus, meconium plugs, ileal
atresia, colonic atresia
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Constipation
> 90% pass meconium in first 24 h
 Present at birth, consider causes of
GI obstruction
 Present after birth, consider
Hirschprung, hypothyroidism, anal
stenosis
 NB some breastfed babies normally
stool only once every 5-7 days
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Diarrhea
Infection
– E coli, salmonella, echovirus,
rotavirus, adenovirus
 Watch for fluid and electrolyte
imbalance
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Jaundice
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First 24 h, always abnormal
Etiology: unconjugated
1. RBC destruction/hemolytic :
– isoimmune, RBC membrane, enzymes,
hemoglobinopathies
– Hematoma
– Sepsis (mixed hemolytic and hepatocellular damage
– Hypoxia
2. Congenital/metabolic:
– Criggler-Najar
– Hypothyroidism, galactosemia
Jaundice
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Later onset: conjugated
1. Hepatocellular damage:
• Viral
• bacterial
• Metabolic: CF, tyrosinemia
2. Post hepatic:
• biliary atresia
• choledochal cyst
Jaundice - Work-Up
History and physical examination
 Bilirubin - total and direct
 Blood type and Coomb’s
 Hemoglobin
 Reticulocyte count
 Smear
 Septic workup
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Risk factors for kernicterus
Prematurity
 Hemolysis
 Asphyxia
 Acidosis
 Infection
 Cold stress
 Hypoglycemia
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Treatment of Jaundice
Nutrition/hydration
 Phototherapy
 Exchange transfusion
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Anemia
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Hemorrhage
– feto-maternal
– feto-placental
– feto-fetal
– intracranial or extracranial
– rupture of internal organs
Hemolysis
Treatment:
– Transfuse if necessary
Polycythemia-Hyperviscosity
Syndrome
Hematocrit > 65 or 70%
 “Sludging” of blood in organ
 May present with:
– respiratory symptoms
– CNS symptoms
– thrombocytopenia
 Treat by partial exchange transfusion
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Bleeding in the Newborn
Hemorrhagic disease of the newborn
 Thrombocytopenia
– immune
– infection related
– congenital
 Disseminated intravascular
coagulation
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Renal issues in the Newborn
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Most common site of congenital malformations
and hence abdominal masses
Renal vein thrombosis: complication of infant of
diabetic mother or polycythemia
Increased risk of UTI’s in uncircumcised males
(but still not as high as infant females)
All newborns have poor concentrating ability;
small prematures at high risk for
fluid/electrolyte imbalance
Endocrine issues in the
Newborn
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Congenital hypothyroidism
– Screen because too late if wait
– Signs = poor feeding, constipation,
prolonged jaundice, large fontanelles,
umbilical hernia, dry skin
Endocrine Issues in the
Newborn
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Congenital adrenal hyperplasia
– 21-hydroxylase deficiency most
common
– Signs = vomiting, diarrhea,
dehydration, shock, convulsions,
clitoris or phallic enlargement
– Watch for electrolyte imbalance
– If suspect, send lab tests and treat
Endocrine issues in the
Newborn
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Infant of diabetic mother
– Congenital malformations (especially important
to have good control preconception)
– Growth disturbances
– Metabolic disturbances: glucose, Ca+ +
– Respiratory distress syndrome and transient
tachypnea of the newborn: more prone
– Polycythemia: jaundice
– Cardiovascular problems: hypertrophic
cardiomyopathy
Hypoglycemia
BS <2.6 prem and bottle fed term
BS <2.0 breastfed
** No clear safe cutoff for all
 Lack of supply
 Lack of reserve (low glycogen): IUGR
 Inability to use/produce: metabolic
 Increased utilization: sepsis
 Increased insulin production
Hypoglycemia
Treat: supply 4-6 mg/kg/min term
6-8 mg/kg/min prem
 Look for cause, especially if severe or
persists beyond 48-72h of life
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Neonatal seizures: etiology
Asphyxia
Infection
Intracranial hemorrhage
Intraventricular hemorrhage
Infarction
Hypoglycemia
Congenital anomaly of CNS
Inborn errors of metabolism
Subarachnoid hemorrhage
46%
17%
7%
6%
6%
5%
4%
4%
2%
The Hypotonic Infant:
Etiologies
Central nervous system disease
 Spinal cord diseases
 Diseases of the peripheral nerve
 Diseases of the neuromuscular
junction
 Muscle Diseases
 Systemic diseases
 Metabolic diseases
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Work-up of Hypotonic
Infant
Exhaustive history
 Complete physical examination
 Imaging: CXR, U/S, CT, MRI
 Nerve conduction velocity,
electromyography
 Serum CPK, AST, CSF protein
 Muscle biopsy, nerve biopsy
 Molecular genetics (myotonic dystrophy,
Prader-Willi)
 Other
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