Download Neonatal Withdrawl Syndrome

Definition of Neonatal
Abstinence Syndrome (NAS)

A condition that an infant experiences
when withdrawing from certain drugs
that his/her mother took during
pregnancy
Incidence

5-10% of deliveries nationwide are to
women who have abused drugs during
pregnancy (excluding alcohol)
Pathophysiology
Drugs of abuse are often of low molecular
weight, water-soluble, and lipophilic
 They are easily transferred across the placenta
to the fetus, and across the blood-brain barrier of
the fetus
 1/2 life of drugs usually prolonged in the fetus
 Drugs either bind to CNS receptors, or affect the
release and reuptake of various
neurotransmitters
 They have long lasting effects on developing
dendritic structures and are toxic to fetal cells

Risk Factors Associated with
an Increased Incidence of
Drug Abuse
Poor socioeconomic circumstances
 Poor education
 Teenage mother
 Poor prenatal care

Other Conditions Associated
with Drug Abuse
Multiple drug abuse
 Poor nutritional status
 Anemia
 Infectious Disease (Hep B, syphilis, HIV,
and other STDs)
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Obstetric Complications
Associated with Drug Abuse
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IUGR
Fetal Distress
PROM
Premature Delivery
Chorioamnionitis
Specific to cocaine: HTN, cardiac
arrhythmias, CVA, abruption, respiratory
arrest, fetal demise
Diagnosis

History:
 Many drug users withhold information
 Details of the quantity and duration of abuse
are unreliable

Labs:
 Urine tox only reflects intake from the last
few days prior to delivery
 False positive immunoassays can occur (i.e.
morphine positive if took in poppy seeds or
codeine from cold/cough medicine)
 More specific chromatography or mass
spectrometry may determine the source
Diagnosis

Labs:
 Meconium analysis reflects drug usage over a
longer period and is more sensitive than urine
○ Disadvantage = specimen requires processing prior
to testing
 Hair analysis is the most sensitive test available
○ Qualitative relationship exists between amount of
drug use and amount incorporated in the hair
○ Newborn hair can be obtained to reflect exposure
during last trimester, and can be obtained later
should symptoms occur where in-utero drug
exposure was previously unsuspected
Diagnosis

Physical Exam:
 Signs and symptoms vary with the
drug(s) used by the mother
 Severity of withdrawal may not correlate
with dose or duration of drug exposure
Signs and Symptoms

CNS
 Hyperirritability
 Increased deep tendon and primitive
reflexes
 Increased muscle tone
 Tremors and myoclonic jerks
 High-pitched cry
 Wakefulness
 Seizures
Signs and Symptoms
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Metabolic/Motor/Respiratory
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Fever
Mottling
Sweating
Lacrimation
Sneezing/congestion
Moaning
Yawning
Hiccups
Increased rooting reflexes
Uncoordinated suck and swallow
Failure to gain weight
Tachypnea/nasal flaring
Signs and Symptoms

GI
 Regurgitation
 Loose stools/diarrhea
Diagnosis
Patients are usually observed for at least 3-5
days for S/S of withdrawal before they are
discharged home
 Abstinence scoring is a way to assess
withdrawal signs
 There are several abstinence scoring systems,
but none have been adopted as the standard
 The Finnegan scoring system is the most
comprehensive and widely used

 A score of 7 or less is considered mild withdrawal and
infants do well with non-pharmacologic comfort measures
 Repeated scores of 8 or more generally indicate the need
for pharmacologic therapy
Studies On NAS

Limitations:
 Urine tox screens do not reflect drug
exposure throughout pregnancy
 Many women who use drugs are multiple
drug users, and also drink alcohol and
smoke cigarettes
 Therefore, it is difficult to isolate the effect
of one drug
Opiates
Most frequent cause of NAS
 Onset of symptoms: Minutes after
delivery to 2-3 days of life
 Clinical course: Variable, can show any
of the s/s mentioned before, s/s can
persist up to 3-6 months
 Prognosis: Good, minimal teratogenicity,
good catch up growth by 1-2 years,
most have normal cognitive and motor
development at 5-6 years with long term
follow-up

Barbiturates
S/S similar to opiates except onset
usually later (4-7 days after birth)
 Duration of s/s usually 2-6 weeks, but
can last as long as 4 months

Benzodiazepines
Not much is known about
benzodiazepines
 S/S similar to opiate withdrawal
 Onset: usually not until 1st few days
after birth
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 However, there has been a reported case
where s/s started 21 days after birth with
chlordiazepoxide use
Alcohol
Foremost drug used today
 Onset: 3-12 hours after delivery
 S/S: More CNS effects, less severe and of
shorter duration than withdrawal from opiates
 More concerning is the risk for Fetal Alcohol
Syndrome
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 35-40% risk in infants born to alcoholic women
 related to alcohol dose
 major cause of mental retardation today
Fetal Alcohol Syndrome (FAS)
 Criteria for FAS:
○ Prenatal or postnatal growth retardation
○ CNS involvement: developmental delays,
behavioral problems
○ Dysmorphic Facial Features: microcephaly,
microphthalmia, short palpebral fissures,
poorly developed philtrum, thin upper lip,
hypoplastic maxilla
 Numerous congenital anomalies are
associated with FAS
 Many don’t meet the criteria, but present
with fetal alcohol effects
Fetal Alcohol Syndrome
Stimulants
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Less common cause of NAS
Usually see s/s that represent the direct
effects of the stimulants themselves
Onset/Duration: Within first 72 hours
S/S: Tremors, high pitched cry, irritability,
excessive suck, hypertonia, tachycardia
Cocaine and Methamphetamine exposed
fetuses have a high rate of spontaneous
abortions, stillbirths, IUGR, prematurity,
and asphyxia related to placental abruption
Stimulants
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Cocaine
 Causes vasoconstriction and decrease in
placental blood flow with consequent fetal
hypoxia
 Acts as a teratogen because of the vascular
effects: CNS & CV anomalies, limb defects,
intestinal atresia
 Prognosis:
○ Usually there is good catch up growth by 1 year
○ There may be speech and behavioral problems
as children get older
○ Studies have shown no difference with respect to
intellectual ability in children who were drugexposed vs. placebo
Stimulants
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Methamphetamine
 Withdrawal symptoms are less severe
 Prognosis: Unclear, may be associated
with neurocognitive deficits
Marijuana
Studies have suggested an increased
risk of prematurity and lower birth weight
 Prognosis: Higher incidence of ADHD
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SSRIs
Cause NAS in up to 1/3 of neonates exposed
in utero
 Onset/Duration: Severely effected present in
1st 48 hours of life and resolve within 48
hours
 S/S: Tremors, hypertonia, irritability, GI
disturbance, respiratory distress
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 S/S usually self-limited & does not require
pharmacologic intervention

Paroxetine with greatest propensity to cause
NAS
Treatment
See Nursery Protocol
 Manifestations of drug withdrawal in
some infants will resolve within a few
days and drug therapy is not required
 The infant’s withdrawal score should be
assessed to monitor the progression of
symptoms and adequacy of treatment
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Treatment
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Treatment should always begin with nonpharmacological measures
 Supportive care:
○ Minimize stimulation - keep baby in a darkened
and quiet environment if possible
○ Swaddling and positioning - use gentle
swaddling and positioning that encourages
flexion rather than extension
○ Prevent excessive crying with a pacifier,
cuddling, etc.
○ Feeding should be on demand if possible
Treatment
Decision for pharmacologic treatment is
based on the infant’s abstinence scores
and mechanism of action of the drug
that the infant was exposed to
 The goal of therapy is to allow the infant
to withdraw without excessive excitation
that leads to withdrawal symptoms
causing discomfort
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Treatment
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Medication Choices and Doses  Morphine Sulfate: high dose = 80-100 mcg/kg
q4 hrs; low dose = 30-40 mcg/kg q4 hrs
 Methadone: 0.05 – 0.2 mg/kg q12-24 hrs
 Buprenorphine: 13.2 mcg/kg/day in 3 divided
doses
 Phenobarbital: Loading = 16mg/kg per 24 hrs;
Maintenance = 2 – 8 mg/kg/day in 2 divided
doses
 Diazepam: 1 – 2 mg q8 – 12 hrs
Treatment
Once a pharmacologic dose has been
advanced to its peak to keep patient
comfortable, the dose is gradually
weaned so the infant can tolerate mild
symptoms of withdrawal
 The length of time it takes to wean an
infant off medication varies from infant to
infant
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Treatment
Opioid withdrawal using oral morphine
sulfate has been shown to be most effective
 Dose can be increased by 20% q8 hrs until
s/s of withdrawal are controlled
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 Max dose: 0.2mg/kg/dose
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Weaning process varies between providers
 Usually the peak dose is maintained x 72hrs,
then wean by 20% every other day
Treatment
Additional use of Phenobarbital and/or
Diazepam is much debated because of
added depressant effects on an infant
who is already on a narcotic
 Phenobarbital mostly used for CNS
withdrawal symptoms
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 It is preferred for non-opiate related NAS
Breastfeeding

Alcohol – Not recommended if use is
excessive
 can cause drowsiness, diaphoresis, deep
sleep, weakness, decreased linear growth,
abnormal weight gain, and decreased
maternal milk production
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Nicotine – Controversial
 crosses into breast milk
 may decrease milk production and cause
the baby to have poor weight gain
Breastfeeding
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Amphetamine - Not recommended
 May cause irritability and poor sleeping
habits
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Cocaine - Not recommended
 May cause irritability, vomiting, diarrhea,
tremors, seizures
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Marijuana - No clear recommendations
 Limited studies
Breastfeeding
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Methadone – Compatible with breastfeeding
 Most opiates are compatible with
breastfeeding except for heroin
 Minimal amounts cross into breast milk and
there is poor oral bioavailability
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Heroin - Not recommended
 May cause tremors, restlessness, poor
feeding, vomiting
Breastfeeding
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SSRIs - Generally safe for breastfeeding
 Sertraline and Paroxetine have minimal
transfer into human milk
 Fluoxetine produces significant plasma
concentrations in some breastfeeding
infants, which can cause:
○ colic, irritability, feeding and sleep disorders,
slow weight gain
 Infants should be monitored for irritability
and poor feeding, or breast milk can be
pumped and dumped
Long Term Management
During the first few years, children
exposed to drugs in utero can have
neurologic problems
 This places a difficult child in a difficult
environment
 Close follow-up and social services
involvement may be required
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