Transcript APNEA, - University of Arizona Department of Pediatrics

APNEA,
ALTE,
and SIDS
Valerie Vickers RNC
Apnea Program Coordinator,
UMC
V Vickers 2002
APNEA is a nonspecific
indicator of distress
Failure of a system
Early indicator of
deterioration
Many known cause of apnea
can be diagnosed and treated.
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PERIODIC BREATHING
•Thought to be benign
•PB  Apnea  SIDS???
Definition of Periodic Breathing:
3 or more pauses for greater than 30
seconds duration with less than 20
seconds of respiration between pauses.
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APNEA
Cessation of respiratory airflow
CENTRAL
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No respiratory effort, no nasal airflow
Developmental phenomenon
OBSTRUCTIVE
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 respiratory effort, no nasal airflow,  HR
Caused by aspiration, laryngospasm or
poor airway control
MIXED
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Both obstructive and central
PERCENTAGE OF APNEA:
 Central 40-45%
 Obstructive 10-15%
 Mixed 40-45%
More premature = more mixed
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INCIDENCE OF APNEA:
•25 % of infants under 2500
grams at birth
•80% of infants under 1000
grams at birth
•25% of infants of all
gestational ages (Rigatto)
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Reflex Effects of APNEA
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sinus bradycardia
drop in blood pressure
change in cerebral blood flow
Apnea and periodic breathing are
common in premature infants after the
first 24 to 48 hours of life.
Premature infants sleep 80% of the
time, term infants 50%. Apnea only
occurs with active sleep.
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CNS Immaturity
 number of synaptic connections
and incomplete dendritic
arborization - cause  sensitivity of
respiratory center to CO2
therefore  in afferent traffic to
reticular formation and reduction
and fluctuation of respiratory center
output
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Other factors contributing to
decreased inspiratory effort:
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 activity of protective respiratory
reflexes
 minute ventilation
diaphragmatic fatigue
soft compliant chest
Therefore
mixed apnea occurs
frequently in premies.
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PATHOLOGIC APNEA
Apnea > 20 seconds with cyanosis,
abrupt, marked pallor or
hypotonia, or bradycardia < 100
bpm
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APNEA OF PREMATURITY (AOP)
 PB with pathologic apnea in a premature infant
 Diagnosis of exclusion
 Usually resolves by 37 weeks post conception but
occasionally persists for several weeks past term
ASYMPTOMATIC PREMATURE INFANTS
 Premature infants who never had AOP or
whose AOP has resolved
SYPMTOMATIC PREMATURE INFANTS
 Premature infants who continue to have
pathologic apnea at the time when they
otherwise would be ready for discharge
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If no other cause found,
the diagnosis is AOP.
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Diagnosis of exclusion
Most common form of apnea in premies
Developmental characteristics are primary
cause due to poor development of both CNS
and airway control
AOP is probably caused by abnormality
in the central control for breathing:
Decreased inspiratory effort and blunted
response to CO2 and O2 plus prolonged
brainstem conduction times result in
hypoventilation and hypercarbia
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Apnea is Associated with Many
Clinical Conditions:
 Intraventricular bleed
May see hypoventilation, apnea or respiratory arrest
 Subtle seizures
Along with fluttering eyelids, drooling or sucking,
tonic posturing
 Sepsis
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Bacterial (GBS, staph. Proteus, Listeria,
Coliforms
Viral (RSV, paraflu, herpes, CMV
Chlamydial
NEC
 Congestive Heart Failure
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PDA and CHD
Due to decreased lung compliance
Respiratory muscle fatigue
Chest wall distortion
Hypoxemia
 Respiratory Distress Syndrome
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Due to atelectasis,  work of breathing, fatigue
May lead to chronic lung disease
 Anemia
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oxygen carrying capacity of blood 
Arterial pressure perfusing CNS 
 Polycythemia
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 blood viscosity and  blood flow to CNS
begins at 2-4 hours of age
 High temperature of environment
 Feeding problems
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overdistention of stomach
aspiration
GER (gastroesphogeal reflux) with or without
aspirations
• due to laryngospasm
• stimulation of irritant receptors in lower esophagus
causing ‘reflux apnea’
• some reflux is common (laundry issue only?)
 Metabolic conditions
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Hypoglycemia
Hypocalcemia
Hypernatremia
Alkalosis
 Others
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Myelomeningocele
Meningitis
ALTE
“APPARENT LIFE THREATENING
EVENT”
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Frightening event to the observer
Combination of apnea
Color change
Marked change in muscle tone
Over 37 weeks conceptual age
Careful Evaluation of Episode
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Obtain accurate report including feeding and
sleeping history
Physical exam, vital signs
Temperature of isolette
CBC, lytes, ABG’s, pulse ox
Blood and viral cultures
Chest xray
Cranial ultrasound
Echocardiogram
pH probe, barium swallow
Placement of feeding tubes (OG/NG)
Computer monitor reports if available
Sleep study
TREATMENT OF APNEA
Dependent on Etiology
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Least invasive
Treat underlying causes
Non-pharmacologic vs
pharmacologic
TREATMENT:
NON-PHARMACOLOGIC
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Tactile stimulation
 neutral ambient temperature
Address feeding issues / GER
Oxygen
Mechanical CPAP / ventilation
• CPAP markedly reduces apneic
episodes with an obstructive
component
• Improves patency of upper airway
by activation of dilator muscles or
by passive splinting
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TREATMENT:
PHARMACOLOGIC
• May treat more severe AOP with
methylxanthines.
• Methylxanthines effect
neurotransmitters and increase
the transmission of impulses
across nerves and synapses.
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METHYLXANTHINES
CAFFEINE
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2.5 - 5 mg /kg / day once per day
(therapeutic range 8-15 mcg/ml)
THEOPHYLLINE
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3-6 mg/kg/day divided in 2 doses
per day
(therapeutic range 6-12 mcg/ml)
METHYLYXANTHINES
(cont.)
Caffeine is often preferable:
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More centrally active
Not metabolized by the liver
However - many pharmacies
do not carry it
Methylxanthines can exacerbate GER
- use the right drug for treatment
NOTE: Neither drug has had
controlled study for efficacy
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GOAL: HOME DRUG FREE
 Goal is to discharge without
methylxanthines
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No apneic events for 5 days
If discharge on methylxanthines,
standard in this community is also
discharge with monitor
May discharge with monitor only and
no medications (rare)
HOME MONITORS
At Risk Group:
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Infants less than 1000 grams
Infants who continue to apnea and bradycardia
Infants requiring methylxanthines to control
apnea
Infants with severe reflux
Infants with tracheostomies
Less risk but for family’s peace of mind
• Infants with severe BPD requiring oxygen
• SIDS sibling or twin of SIDS
• Infants with non-repeated ALTE
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CRITERIA FOR SUCCESS
OF HOME MONITORING
 Training is crucial!
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Apnea class including CPR
Caregivers have adequate time to
use equipment prior to discharge
 Support is imperative!
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Support system includes: medical,
technical, psychosocial, community
support
 Choose the right monitor!
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TERMINATION OF MONITOR USE
 Usually by 6 months of age
 No significant apnea for 2 months
 If on methylxanthines, 1-2 weeks after
discontinuation of medications and not
significant apnea
 Resolution of primary problem
MONITORING CANNOT
GUARANTEE SURVIVAL
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SUDDEN INFANT DEATH
SYNDROME (SIDS)
Sudden death of any infant or young
child which is unexplained by
history and in which a thorough post
mortem fails to demonstrate and
adequate cause of death.*
*Definition taken from the NIH Consensus
Development Conference on Infantile Apnea and
Home Monitoring
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SIDS STATISTICS
 1-2 deaths per 1000 live births per year
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with Back to Sleep campaign in the US - 
by 40%
leading cause of death in infants older than
one month
 Most common age for SIDS is 2-4 months
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99% of deaths before 6 months
1 % of deaths 6-12 months
extremely rare in the 1st month of life
infants have change in response to hypoxia
around 6 months of age
SIDS FACTS
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SIDS risk for an infant with AOP or who has
had an ALTE is at no greater risk than the
general population
Premature infants have a slightly greater risk
which increases as their gestational age
decreases
Home monitoring of infants has NOT
decreased the incidence of SIDS
The SIDS sibling is not at greater risk of SIDS
than the general population
SIDS PREVENTION
Research indicates that SIDS is
more complex than a single
abnormality in a single system.
 Failure of arousal mechanism
 Ethnicity is a factor
 Back to Sleep campaign
 AAP discourages the use of monitors
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SIDS RESEARCH
Research indicates that SIDS is more complex
than a single abnormality in a single system.
 Research findings:
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Supine sleeping position most protective, side lying better
than prone but not protective as supine
Overheating contributory
Smoking contributory
Any breastfeeding is protective
Research indicates SIDS is a malfunction in arousal
CHIME study indicates that normal infants have apnea,
bradycardia and desaturations into the 70’s - question
why they can recover and the infant who dies of SIDS
does not
Tachycardia then bradycardia prior to fatal event - not
necessarily proceeded by apneic event