Central Sleep Apnea in Adults:
Causes and Treatment
Timothy Daum MD
Spectrum Health
Grand Rapids
Rogers, R. Chest 2008;133:598
The majority of sleep apnea we
see is obstructive in nature:
Central Sleep Apnea
• At most 10% of sleep study population
• Pathogenesis
– Distinguishing characteristics
• Approach to management
Central Sleep Apnea
• Sleep transition central apnea
• Congenital Alveolar Hypoventilation
– Ondine’s Curse
• CHF
– Cheyne-Stokes Periodic Breathing
•
•
•
•
•
Stroke or Other Neurologic Insult
High Altitude Periodic Breathing
Narcotics
Treatment Emergent Central Apnea
Complex Sleep Disordered Breathing
CSA: Symptoms
• Disrupted, unrefreshing sleep
• Many complain of insomnia
• Excessive daytime sleepiness
Sleep Transition Central Apnea
• Common with recurrent arousals
– OSA, PLMS
• CO2 will climb from 40 to 45 in normal
sleep
• Robust ventilatory response with arousal
• CO2 driven below ventilatory threshold
• Apnea with sleep onset
Sleep Transition Central Apnea
Sleep Transition Related Central
Apnea
Congenital Alveolar
Hypoventilation
• Ondine’s curse
• Due to recently recognized genetic
abnormality
• Affected individuals have higher CO2 set
point
• Usually identified in infants
– Milder cases found in adults
• Responds well to timed Bilevel Pressure
CSA and CHF
• Up to 40% of those with reduced LVEF
• Most common with:
– More advanced age
– Male
– Atrial fibrillation
• Presence of CSA portends a worse
prognosis
SDB in CHF Patients
New York Heart Association
Level I
Level II
Level III
Level IV
OSA
CSA
CSA and CHF:
Cheyne-Stokes Periodic Breathing
• Note period length of 60-90 sec
• Note circulation time. Usually over 30 seconds in CHF.
CHF and CSA: Pathogenesis
• Dyspnea leads to hyperventilation and hypocapnea
while awake
• With sleep onset, hypocapnea leads to apnea and
hypoventilation
• With increased circulation time, hypercapnea
becomes significant before blood gets from lungs
to brain stem leading to marked hyperventilation
• Hyperventilation leads to hypocapnea
• Repeat
CHF and CSA: Treatment
• Main therapy is optimize medical
management of CHF
• Positive airway pressure shown to:
–
–
–
–
Improve exercise tolerance
Improve LVEF
Decrease catecholamines
Quality of Life
• No proven benefit on mortality
CHF and CSA: Alternative
Treatments
• Oxygen
– May decrease dyspnea and hyperventilation
• Theophylline
– Respiratory stimulant
• Adaptive Servo Ventilation
CSA and CVA
• Present in 26% of acute stroke patients
• Continues in 7% long term
• Remember the high incidence of OSA in
stroke patients as well
– Unclear if this precedes CVA
CSA and Narcotics
• Can be seen in up to 50% of chronic narcotic
users.
• Prevalence almost certainly increasing.
Treatment Emergent Central
Apnea
• Titration of CPAP beyond that needed to
resolve obstructive events can lead to the
development of central events with
arousals.
• Important to differentiate from complex
sleep apnea
– Central events seen before obstructive events
controlled
Complex Sleep Disordered
Breathing
• Traditional classification is obstructive vs
central sleep apnea
• Recently recognized group of patients who
start out looking like mostly OSA but
develop prominent CSA with CPAP
• Central apneas develop before obstructive
events controlled
Complex SDB: Baseline
Complex SDB: CPAP
What Do We Know About
CompSA?
• Prevalence: Estimated to be 15% of SDB
population
• About 50% don’t ever respond to CPAP
– Residual symptoms (fatigue, sleepiness, depression)
– Intolerance to therapy
• Dramatic improvement during REM sleep (reverse
of pattern seen in OSA)
• No distinguishing clinical profile
Morgenthaler et al, Sleep, 2006
CSA: Treatment
CSA: Treatment
• Maximize medical therapy of underlying
condition
– Diuretics; afterload reduction; beta-blockers,
biventricular pacers for CHF
– Minimize narcotics and other sedatives
• Trial CPAP
– Often unresponsive
Adaptive Servo Ventilation
• Servo: Any type of self-regulating feedback
system or mechanism
• VPAP Adapt SV
– ResMed
• BiPAP auto SV
– Respironics
PAP Therapy
™
How Does it Work?
• Creates a Target Ventilation
– The ASV algorithm monitors recent average minute
ventilation (~3 min window)
– It continuously calculates a target ventilation
throughout the night (90% of recent average
ventilation)
• Ventilates to the Target
– Algorithm monitors patient ventilation and compares it
to the target ventilation
– Adjusts pressure support up or down as needed to
achieve target
End Expiratory Pressure (EEP)
• EEP = EPAP
• Default EEP = 5 cm H20
– May adjust in 1-2 cm increments to resolve any upper airway
obstruction (for CHF patients wait 40 minutes before adjusting)
EEP: manually
titrate like CPAP
to hold airway
patent
Pressure
(cm H20)
Time
Pressure Support (PS)
• Pressure support = IPAP - EPAP
• Pressure support varies between limits
– minPS (default 3 cm H2O)
– maxPS (default 10 cm H2O)
• Values are adjustable but defaults work in almost all cases
maxPS
Pressure
(cm H20)
minPS
Time
Gives Support Only When
Needed
The ASV algorithm automatically adjusts the magnitude of pressure
support breath by breath to:
– Provide minimal, comfortable support during the over-breathing
phase (hyperpnea) or during normal breathing
– Increase support during under-breathing
(hypopnea or apnea)
Normal
breathing effort
Central apnea
(no spontaneous effort)
Pressure
(cm H20)
Time
Support When Needed
Effort
Flow
FG
SpO2
Normalized Breathing:
10 Minutes Into Session
Effort
Flow
FG
SpO2
Greatest Reduction in
Central Apnea Index
• 83% further reduction
in CAI compared to
CPAP
• 50% reduction
compared to bilevel
Teschler et al, AJRCCM, 2001
Normalizes Total Arousal Index
• Partial improvement
with oxygen and
CPAP
• Normalization with
bilevel and ACS
Teschler et al, AJRCCM, 2001
Significant Increase in Deep Sleep
• SWS+REM = % time
spent in deep,
restorative sleep
• Large increases in
SWS+REM with ASV and
bilevel but not with either
O2 or CPAP
Teschler et al, AJRCCM, 2001
CMS Guidelines for CSA
(E0471)
Conclusion
• By now, you should be able to:
– List the ideal types of patients for VPAP Adapt SV
– Describe how the VPAP Adapt SV treats patients
– Discuss the results of studies using ResMed’s Adaptive
Servo-Ventilation algorithm
– List the keys to successful treatment
– State the qualifying criteria and reimbursement
guidelines for the VPAP Adapt SV