Pediatric Sleep Scoring Issues
Patrick Sorenson, MA, RPSGT
Infant & Pediatric Scoring
April, 2011
NESS
Newport, RI
Staging Section
Newborn: Sleep-Wake
Cycles
Ultradian
A newborn spends
approx. 70% of every
24 hrs in sleep.
Cycles last about 40-60
minutes
Feedings occur about
every 3-4 hours-use
demand not
schedules.
Quiet
sleep
Active
Sleep
Awake
REM/NREM
Developmental
Distributions
90%
80%
70%
60%
50%
REM
NREM
40%
30%
20%
10%
0%
Premies
Infants
Toddlers
Teens
Adults
Quiet Sleep (QS, Stage N)
Quiet sleep is analogous to NREM sleep
• EEG - characterized by high amplitude (14 to
35 µV), slow wave (0.5-5 Hz) patterns.
• Trace’ Alternant patterns consist of 2 to 6
second bursts of high amplitude slow waves
separated by 4 to 8 seconds of low-voltage
mixed activity. TA appears by about 28
weeks GA, becomes associated with QS by
~32 weeks. TA appears in its mature form by
~36 weeks.
Quiet Sleep-EEG
findings, cont.
• Sleep spindles appear by ~4 weeks and
develop rapidly through 8 weeks of age and
clearly characterize NREM sleep by 3 months
of age.
– Coincidental with the social smile.
• K-complexes first appear at ~4-6 months and
are fully developed by about 2 years of age.
Quiet SleepPhysiological Findings
• Slower cardiac rhythm as
compared to Active Sleep
• Slower respiratory rates
• Resting levels of muscle
tone
Active Sleep (AS, Stage R)
Active Sleep is analogous to REM sleep
• EEG is characterized by low-voltage fast
desynchronous activity w/bilaterally
synchronous REM’s.
• Variable frequency ranges from 14-35 µV
(usually in the 20-30 µV range).
Active Sleep (Stage R) Physiological Findings
• Increased or variable cardiac rate
• Increased or variable respiratory rate;
primarily costal in nature
• Out-of-phase chest and abdominal effort
channels. Inhibition of muscle tone in infant’s
chest wall musculature.
• Frequent brief movements, grimaces,
peeking, vocalizations, grunts, sucking,
tremors & squirming are all common in AS.
Esophageal pH
• Ability to interface pH equipment with
polygraph and slow-chart writer
• Examine the relationship between GER
and apnea
• GER is most commonly seen during
fussy wakefulness
• Document all feeds, meds and GER
episodes
2007 AASM Rules for Staging Children
• Pediatric sleep scoring rules start at 2 months postterm
• Same terminology as adults with addition of NREM
(N) as depending upon features seen.
• N = Ø K’s, spindles or high amp slow-wave (0.5-2 Hz)
• N2 = presence of K’s and spindles
• Once N2 & N3 features are present, begin scoring as
older child/adult – N1, N2, N3 & R.
• Usually 5-6 months PT, but sometimes as young as
4-4.5 months.
2007 AASM Rules for Staging Children –
Dominant Posterior Rhythm (DPR)
• DPR changes with age
– 3.5-4.5 Hz 3-4 months PT
– 5-6 Hz by 5-6 months PT
– 7.5-9.5 Hz by 3 years.
• Amplitude also changes
• Still score sleep onset if DPR ≤
50% of the epoch
• Eye movements are key!
Incidence of sleep
terrors
• Confusional arousals seen in about 510% of all children, though regular
nighttime awakenings are seen in 5070% of children 2-10 years old.
• Occur in about 3% of prepubertal
children and less than 1% of adults.
• Onset of symptoms is about 2-4 years.
Can occur at any age.
• General sleep architecture
w/vulnerable transition periods.
W
1
?
REM
2
3
4
1
2
3
4
Hour
5
6
7
8
Begin Respiratory
Section
The “How to”
• Sensor used to detect absence of airflow for identification of an apnea is an
oronasal thermal sensor
• Sensor for detection of airflow for identification of a hypopnea is a nasal air
pressure transducer without the square root transformation of the signal
• Acceptable sensors for detection of respiratory effort are either esophageal
manometry, or calibrated or uncalibrated inductance plethysmography
• Sensor for detection of blood oxygen is pulse oximetry with a maximum
acceptable signal averaging time of 3 seconds
• Acceptable methods for assessing alveolar hypoventilation are either
transcutaneous or end-tidal CO2 monitoring
Sleep Foundations
27
Oxygenation
Sensors
• Pulse oximetry
• < 3 seconds averaging time
• Pulsewave =
plethysmograph
Nasal pressure in children
• Need:
– More than one airflow measure.
– Way of simultaneously measuring
PCO2.
Dual PN / CO2 system
(commercial)
Age Criteria
• Criteria for respiratory events
during sleep for infants and
children can be used for children
<18 years, but an individual sleep
specialist can choose to score
children ≥ 13 years using adult
criteria.
Sleep Foundations
31
Normative data ages 1-17 y
6
5
4
N
3
2
1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17
Age (y)
Marcus, Am Rev Respir Dis 1992; 146:1235
Results
• Obstructive AI = 0.1 + 0.5 / hr
• Obstructive AHI = 0.2 + 0.6 / hr*
*Witmans, AJRCCM 2003; 168:1540
Normative data ages 1-15 y
Uliel, Chest 2004; 125:872
Results
• Mean obstructive AI = 0 / hr
• Mean obstructive AHI = 0 / hr
The Rules
Score a respiratory event as an obstructive apnea if it meets all of the
following criteria:
•
 Event lasts for at least 2 breaths (or the duration of 2 breaths as
determined by baseline breathing pattern)
•
 Event is associated with a >90% fall in the signal amplitude for
≥ 90% of the entire respiratory event compared to the pre-event baseline
amplitude
•
 Event is associated with continued or increased inspiratory effort
throughout the entire period of decreased airflow
•
 Duration of the apnea is measured from the end of the of the last
normal breath to the beginning of the first breath that achieves the preevent baseline inspiratory excursion
Sleep Foundations
36
Obstructive apnea
Definition
MEETS ALL OF THE
FOLLOWING:
• > 2 missed breaths
• > 90% fall in flow amplitude
• No arousal / SaO2 criteria
Mixed Events?
Score a respiratory event as a mixed
apnea if it meets both duration and
flow amplitude criteria, and it is
associated with absent inspiratory
effort in the initial portion of the
event, followed by resumption of
inspiratory effort before the end of
the event
Sleep Foundations
39
Central Events
Score a respiratory event as a central apnea if it is
associated with absent inspiratory effort throughout
the entire duration of the event and one of the
following is met:
•
•
 Event lasts 20 seconds or longer
 Event lasts at least 2 missed breaths (or the
duration of 2 breaths as determined by baseline
breathing pattern) and is associated with an
arousal, an awakening or a ≥ 3% desaturation
Sleep Foundations
40
Central Event
Central Apnea > 20 sec
(Infants)
Duration of apnea (sec)
40
36
32
28
24
20
16
0
2
4
6
8
10
12
14
16
Age (weeks)
Hunt, Pediatr Res 1996; 39:216
18
20
Infant CA, cont.
• Apnea of Prematurity: Slowed or retarded
maturation of the Arcuate Nucleus and
Carotid Chemoreceptors can inhibit natural
respiratory drive mechanisms
• Central Apnea commonly follow sighs as the
drive to breathe is temporarily inhibited
• Periodic Breathing consists of central pauses
of 3 or more seconds followed by normal
breathing for up to 20 seconds
Infant CA, cont.
• Periodic Breathing is most prevalent in
premature infants and is usually
separated by bursts of 2-4 quick breaths
between complete respiratory drive
inhibition
• By 3 months, normal PB consists of <
3% of total sleep time
• Respiratory drive seems to be reset at
birth
Apnea of Prematurity
Can worsen with:
• Anemia-below normal reduction of
erythrocytes in the quantity of hemoglobin.
• Septicemia-pathogenic microorganisms or
their toxins are present in the blood.
• Hypoxia-reduced O2 supply to tissue.
• GER-Gastroesophageal Reflux.
• Seizures-electrical disturbance of the CNS.
Pediatric Hypopnea Rules
Score a respiratory event as a Hypopnea if it meets all of the following criteria:
•
 Event is associated with a ≥ 50% fall in the amplitude of a nasal
pressure or alternative signal compared to the pre-event baseline
excursion
•
 Event lasts at least 2 missed breaths (or the duration of 2 breaths as
determined by baseline breathing pattern) from the end of the last normal
breathing amplitude
•
 The fall in the nasal pressure signal amplitude must last for ≥ 90% of
the entire respiratory event compared to the signal amplitude preceding
the event
•
 Event is associated with an arousal, awakening or ≥ 3% desaturation
Sleep Foundations
46
Hypopnea
Definition
• MEETS ALL OF THE
FOLLOWING:
• > 2 missed breaths
• > 50% fall in amplitude
• Arousal / awakening / > 3%
desaturation
RERA’s
Score Respiratory Effort Related Arousal (RERA) if conditions below are met:
•
When using a nasal pressure sensor all of the following must be met:
–  Discernable fall in the amplitude of signal from a nasal pressure
sensor, but it is less than 50% in comparison to the baseline level
–  Flattening of the nasal pressure waveform
–  Event accompanied by snoring, noisy breathing, elevation in the endtidal PCO2, transcutaneous PCO2, or visual evidence of increased work
of breathing
–  Duration of event is at least 2 breath cycles (or the duration of 2
breaths as determined by baseline)
Sleep Foundations
48
RERA definition (PN)
•
•
•
•
•
MEETS ALL OF THE FOLLOWING:
< 50% fall in amplitude
Flattened waveform
> 2 breaths
Snoring, WOB, CO2
Use of Pes for RERA
When using an Esophageal Pressure Sensor (Pes) all of the
following must be met:
•
 There is a progressive increase in inspiratory effort during
the event
•
 Event is accompanied by snoring, noisy breathing,
elevation in the end-tidal PCO2, transcutaneous PCO2 or
visual evidence of increased work of breathing
•
 Duration of the event is at least 2 breath cycles (or the
duration of 2 breaths as determined by baseline breathing
pattern)
Sleep Foundations
50
RERA definition (Pes)
MEETS ALL OF THE FOLLOWING:
• Progressive increase in
inspiratory effort
• > 2 breaths
• Snoring, WOB, CO2
Child with UARS
Flow
Chest
Abdo
Pes
*
*
*

Hypoventilation Rule
Score the presence of sleeprelated hypoventilation when
>25% of the total sleep time as
measured by either the
transcutaneous PCO2 and/or tidal
CO2 sensor(s) is spent with a CO2
>50 mm Hg.
Sleep Foundations
53
Noninvasive CO2 measurements
• Moderate to high correlations between
transcutaneous / end-tidal and arterial CO2.
• Largest discrepancies occur in hypercapnic
subjects or subjects with respiratory disease.
• End-tidal CO2 tends to underestimate arterial
CO2.
• Transcutaneous CO2 tends to have a smaller
bias then end-tidal PCO2, with a tendency for
overestimating CO2.
ETCO2 Waveform
•1. Inspiratory baseline
•2. Expiratory upstroke
•3. Expiratory plateau
•4. Inspiratory downstroke
ETCO2 is range-based.
Individual values are of little
use.
Torr & mm/Hg mean the same
thing
The capnograph trace
End-tidal measurements
• Breath-by-breath changes
• Need good waveform with
plateau
• Uncomfortable
• Poor signal:
– Mouth-breathing
– Secretions
– Tachypnea, small lung volumes
Transcutaneous measurements
• Slow response rate
• Well tolerated
• Problems:
– Burns – Required repositioning
every 4 hours
– Poor perfusion
– Skin lesions

Periodic Breathing Rule
Score Periodic Breathing if there
are: >3 episodes of central apnea
lasting > 3 seconds separated by
no more than 20 seconds of normal
breathing
Sleep Foundations
61
Sudden Infant Death Syndrome
(SIDS)
The sudden and unexpected death of
an infant for which sufficient cause
cannot be found by a death scene
investigation, review of the history, and
a postmortem examination.
Respiratory Drive Chart
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Birth-FT 1 week 2 weeks 3 weeks 1 month
Thermoregulation
Chemoreception
This graph shows the rate per 1,000 live births for infant deaths during the neonatal period (between the
ages of birth through 27 days) in the United States.
PSG night-to-night variability
(sleep architecture)
100
80
60
Night 1
Night 2
40
20
0
Sleep
Efficiency
REM
(% TST)
Arousal Index
(N/hr)
(%)
Katz, J Pediatr 2002; 140:589
PSG variability
(respiratory)
100
80
60
Night 1
Night 2
40
20
0
AHI
(N/hr)
SaO2 Nadir
(%)
Hypoventilation
(% TST)
Katz, J Pediatr 2002; 140:589
Reliability of infant
respiratory scoring
• Scoring of apnea
• Based on RIP
• k = 0.65
• After training: k = 0.85
Corwin, Pediatr Res 1998; 44:682
Summary
• Most scoring is similar to
former ATS pediatric criteria.
• Established the 1st criteria
for pediatric hypopnea
scoring.
Major differences between
pediatric and adult scoring
• CA scoring: > 20 seconds OR
associated abnormalities.
• Obstructive events: > 2
breaths.
• CO2 usually measured.
Time for questions?
• Please use microphone if
available.