Complex Sleep Apnea:Complex Sleep Apnea: Clinical ChallengesClinical ChallengesComplex Sleep Apnea:Complex Sleep Apnea: Clinical ChallengesClinical Challenges

Brian J. Bohner, M.D.Brian J. Bohner, M.D.Diplomate ABSMDiplomate ABSM

Fellow AASMFellow AASM

CBTS CBTS Sept 14, 2012Sept 14, 2012

Complex Sleep ApneaComplex Sleep Apnea Clinical Challenges: Clinical Challenges:

ObjectivesObjectives

Definition of Complex Sleep Apnea

Causes of Central Apnea Developing on CPAP Therapy

Natural History

Diagnostic and Therapeutic Challenges

Case Study – T.Y.Case Study – T.Y.Case Study – T.Y.Case Study – T.Y. 54 Y.O. Male C/O:

1. Daytime Sleepiness/Fatigue2. 5-10 Awakenings per Night3. Snoring

PMH:1. HTN2. Lumbar Arthritis3. No history or symptoms of CHF

Medications:1. Celebrex2. Metoprolol3. No opiates

ROS:1. Chronic nasal congestion

Exam: Wt = 199 lbs, (BMI = 27) Moderate nasal congestion

ESS (Epworth Sleepiness Scale): 16

Baseline PolysomnogramBaseline PolysomnogramBaseline PolysomnogramBaseline Polysomnogram

Baseline PolysomnogramBaseline Polysomnogram

Polysomnogram Results:Polysomnogram Results:Polysomnogram Results:Polysomnogram Results:Apnea Index = 21.3Apnea + Hypopnea Index = 43.1Total Sleep Time = 4.8 HoursO2 Saturation Nadir = 84%

Trial of Automatic CPAP:

AHI 18. 22 min large leak.

CPAP Titration StudyCPAP Titration StudyCPAP Titration StudyCPAP Titration Study

CPAP Titration – CPAP Titration – Development Development

of Central Eventsof Central Events

CPAP Titration – CPAP Titration – Development Development

of Central Eventsof Central Events

Complex Sleep Apnea:Complex Sleep Apnea:DefinitionDefinition

Complex Sleep Apnea:Complex Sleep Apnea:DefinitionDefinition

Complex Sleep Apnea is a form of sleep apnea in which central apneas persist or emerge (CAI >5) during attempts to treat obstructive events with nCPAP or Bilevel PAP.

Patient CharacteristicsPatient CharacteristicsPatient CharacteristicsPatient Characteristics1. > 90% are Male (ref 14)2. BMI is slightly less than average

OSA patient (ref 16)3. ? Higher incidence of ischemic

heart disease or CHF (ref 15)4. Slight predominance in atrial

fibrillation, opiate use (ref 1 and 2)

5. ? Elevated nasal resistance (ref4)

Natural History of Complex Natural History of Complex ApneaApnea

• Prevalence of syndrome- 5.7 to 20%.

• In 78%- 92% of pts, CAs resolve within months in CPAP adherent patients.

• Of pts without Com SA on initial CPAP titration, 4% developed it on 3 mo f/u !!

• Ref 1 and 2

Polysomnographic Polysomnographic CharacteristicsCharacteristics

Polysomnographic Polysomnographic CharacteristicsCharacteristics

May have evidence of central events on baseline PSG (CAI >5) (ref 1)

Events more common in nREM sleep (ref 16)

Elevated Arousal Index (ref 16)

On F/U CPAP titration in 2-3 months, persistent CA more likely if severe OSA or CSA >5 (ref 1)

Clinical Impact of nCPAP in Clinical Impact of nCPAP in “Complex Apnea”“Complex Apnea”

Clinical Impact of nCPAP in Clinical Impact of nCPAP in “Complex Apnea”“Complex Apnea”

1. Residual or Worsening Symptoms(Fatigue, EDS, Depression) Secondary to Arousals/Disrupted Sleep

2. Higher Incidence of “CPAP Difficulty” (ref18)

3. ↑ Sympathetic Activity (ref 18)

A.Behavioral

B.Metabolic

1.Chemoreceptors

a.Carotid Bodies

b.Medulla

44

36

Eupnea

Apnea Threshold

CO2 Reserve

Controls of Breathing: AWAKEY

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Controls of Breathing - Controls of Breathing - SleepSleep

38Apnea

Threshold

REM

nREM

1. Loss of Behavioral Control

2. Narrow CO2 Reserve in nREM

3. Hypoxia Further Reduces pCO2

4. Metabolic Acidosis Widens CO2 Reserve

Y a

xis

=

pC

O2

CO2

ReserveApnea Threshold

CO2

Reserve39

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Controls of Breathing During SleepControls of Breathing During Sleep - -

CHFCHF

1. Pulmonary Afferent Receptors

pCO2

Apnea Threshold

2. Loop Gain

A. Increased Response to pCO2 B. Increased Lung to Peripheral

Chemoreceptor Circulation Time

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Controls of Breathing During SleepControls of Breathing During SleepEffects of nCPAP/Bilevel PAPEffects of nCPAP/Bilevel PAP

1. Effect of Opening Airway - ↑ Minute Ventilation (Increases plant gain)

2. Fragmented Sleep with Arousal – (discomfort/ elevated nasal resistance)

3. PAP induced distention of stretch receptors (Hering Breuer inflation reflex)

pCO2

Apnea Threshold

CO2

Reserve

Diagnostic ChallengesDiagnostic Challenges

1. Increasing number of patients not undergoing CPAP titration

2. Autotitrating PAP devices vary in ability to warn clinician of emerging central apnea

3. Failure to diagnose Complex Apnea may lead to poor compliance and abandonment of PAP therapy.

4. Overtitration may result in inappropriate dx.

Waveform Report Waveform ReportSo here is what’s going on So here is what’s going on

Therapy for Complex ApneaTherapy for Complex Apnea

1. Adaptive Servo Ventilation

2. nCPAPClose F/U, permissive flow limitation/ additional dead space

3. Supplemental 02

4. Medications benzodiazepines/ acetazolamide

Adaptive Servo Ventilation Adaptive Servo Ventilation (ASV)(ASV)

Adaptive Servo Ventilation Adaptive Servo Ventilation (ASV)(ASV)

Airway Pressure Device devised for Treatment of CSA/CSR as well as Complex Apnea

Automatic Pressure Support (Dynamically Calculated) to result in Consistent Tidal

Volume

Automatic Backup Rate (Calculated)

Multiple Studies show Effective Clinical Results in Treating Complex Apnea

RespironicsRespironics

BiPAP Auto SV

Responds to Peak Flow and Adjusts Pressure Support Accordingly

Manufacturers Suggestion for Settings:

Set EPAP or EPAP min Set PS 2-15 Set IPAP max = 25 Rate = auto

Breath to Breath

Pressure Support

Backup Breath

Stabilization of Breathing

BiPAP Auto SVBiPAP Auto SV

Res MedRes MedRes MedRes Med♠ VPAP Adapt SV

♠ Algorithm Directed at Measuring “Baseline” TV and Respiratory Rate

♠ Can Titrate for EPAP (EEP) or use “Default Setting” of 5 cm

♠ IPAP Suggestions: Set Min PS = 3 cm Set Max PS = 10 cm

The VPAP Adapt SV The VPAP Adapt SV ResponseResponse

The VPAP Adapt SV The VPAP Adapt SV ResponseResponse

VPAP Adapt SV (ASV mode on)

Airflow

HYPOPNEAAPNEA

Adapt SV responds to apnea by increasing support

(Apnea converted to a hypopnea & breathing quickly normalized by VPAP Adapt SV)

CSA/CSR Returns Without CSA/CSR Returns Without TreatmentTreatment

CSA/CSR Returns Without CSA/CSR Returns Without TreatmentTreatment

VPAP Adapt SV

Airflow

ASV mode turned off

(CSA/CSR rapidly returns)Off

Comparison Comparison

• VPAP Adapt ASV (n=35)

• Avg use 5.0

• Change ESS -2.5 • % nights > 4 h 67

• CMS compliant % 34

• BIPAP Auto ASV (n=41)

• 6.0• -4• 73.5 • 51

• Reference 3

Patient T.Y. On ASVPatient T.Y. On ASVPatient T.Y. On ASVPatient T.Y. On ASV

Therapeutic ChallengesTherapeutic ChallengesTherapeutic ChallengesTherapeutic Challenges

1. Adaptive Servo Ventilation costly

2. nCPAP may eventually be adequate therapy.

3. Other therapies not well studied.

Conclusions/ SuggestionsConclusions/ Suggestions

Clinicians caring for all OSA pts need proper training/ education given prevalence and natural history of Complex SA.

Difficult to predict patients who will develop the syndrome.

Prevalence of the syndrome highlights importance of CPAP titration study in OSA patients.

Conclusions/ Suggestions (cont)Conclusions/ Suggestions (cont)Conclusions/ Suggestions (cont)Conclusions/ Suggestions (cont)• Treatment decision generally pertains to ?

ASV vs close f/u on CPAP

• Insurance carriers may impact on these decisions

• Suggest confirming emergent CAs prior to ASV titration

• Consider 02 and pharmacologic agents

• Need to consider best therapy for pt, but sensitive to costs (CPAP titration/ ASV)

For More Info: www.smaminfo.com

ReferencesReferencesReferencesReferences

1. Javaheri The prevalence and Natural History of Complex Sleep Apnea JCSM No 3, 2009 205-211

2. Hoffman The Appearance of Central Sleep Apnea after Treatment of Obstructive Sleep Apnea

Chest Aug 2012 517-522

3. Kuzniar Comparison of two servo ventilator devices in the treatment of complex sleep apnea

Sleep Medicine (2011) 2010.09.017

4. Nakazaki Continuous positive airway pressure intolerance associated with elevated nasal resistance is a possible mechanism of complex sleep apnea Sleep Breath (2012) 16:747-752

ReferencesReferencesReferencesReferences

5 Efficacy of adaptive servoventilation in treatment of complex and central sleep apnea syndromes.Chest. 2007 Dec; 132 (6): 1839-1846.PMID: 18079219 [PubMed – indexed for MEDLINE]

6. CPAP should be used for central sleep apnea in congestive heart failure patients.J Clin Sleep Med. 2006 Oct; 15;2 (4): 394-398.PMID: 17557465 [PubMed – indexed for MEDLINE]

7. Brown LK, Casey KR.Complex sleep apnea: the hedgehog and the fox.Curr Opin Pulm Med. 2007 Nov; 13 (6): 473-478.PMID: 17901751 [PubMed – indexed for MEDLINE]

8. The significance and outcome of continuous positive airway pressure-related central sleep apnea during split-night sleep studies.Chest. 2007 Jul; 132 (1): 81-87. Epub 2007 May 2.PMID: 17475636 [PubMed – indexed for MEDLINE]

ReferencesReferencesReferencesReferences

9. Chest. 2007 Feb; 131 (2): 595-607. ReviewPMID: 17296668 [PubMed – indexed for MEDLINE]

10. Recognition and management of complex sleep-disordered breathing.Curr Opin Pulm Med. 2005 Nov; 11 (6): 485-493. Review.PMID: 16217173 [PubMed – indexed for MEDLINE]

11. Javaheri S.Acetazolamide improves central sleep apnea in heart failure: a double-blind, prospective study.Am J Respir Crit Care Med. 2006 Jan 15; 173 (2): 234-237. Epub 2005 Oct 20.PMID: 16239622 [PubMed – indexed for MEDLINE]

12. Kuzniar TJ, Golbin JM, Morgenthaler TI.Moving beyond empiric continuous positive airway pressure (CPAP) trials for central sleep apnea: a multi-modality titration study.Sleep Breath. 2007 Dec; 11(4): 259-266.PMID: 17541664 [PubMed – in process]

ReferencesReferencesReferencesReferences13. Kuzniar TJ, Pusalavidyasagar S, Gay PC, Morgenthaler TI.

Natural course of complex sleep apnea – a retrospective study.Sleep Breath. 2007 Sept 15; (Epub ahead of print)PMID: 17874254 [PubMed – as supplied by publisher]

14 . Lehman S, Antic NA, Thompson C, Catcheside PG, Mercer J, McEvoy RD.Central sleep apnea on commencement of continuous positive airway pressure in patients with a primary diagnosis of obstructive sleep apnea-hypopnea.J Clin Sleep Med. 2007 Aug 15; 3 (5): 462-466.PMID: 17803008 [PubMed – indexed for MEDLINE]

15. Morgenthaler TI, Gay PC, Gordon N, Brown LK.Adaptive servoventilation versus noninvasive positive pressure ventilation for central, mixed, and complex sleep apnea syndromes.Sleep. 2007 Apr 1; 30 (4): 468-475.PMID: 17520791 [PubMed – indexed for MEDLINE]

16 Morgenthaler TI, Kagramanov V, Hanak V, Decker PA.Complex sleep apnea syndrome: is it a unique clinical syndrome?Sleep. 2006 Sept; 7 (6): 474-479. Epub 2006 Aug 23.PMID: 16931153 [PubMed – indexed for MEDLINE]

ReferencesReferencesReferencesReferences17. Papacostas SS, Myrianthopoulou P, Dietis A, Papathanasiou ES.

Induction of central-type sleep apnea by vagus nerve stimulation.Electromyogr Clin Neurophysio. 2007 Jan-Feb; 47 (1): 61-63.PMID: 17375884 [PubMed – indexed for MEDLINE]

18. Pusalavidyasagar SS, Olson EJ, Gay PC, Morgenthaler TI.Treatment of complex sleep apnea syndrome: a retrospective comparative review.Sleep Med. 2006 Sept; 7 (6): 474-479. Epub 2006 Aug 23.PMID: 16931153 [PubMed – indexed for MEDLINE]

19. Thomas RJ.Effect of added dead space to positive airway pressure for treatment of complex sleep-disordered breathing.Sleep Med. 2005 Mar; 6 (2): 177-178. Epub 2005 Jan 25. PMID: 15716223 [PubMed – indexed for MEDLINE]

20. Wang D, Teichtahl H, Drummer O, Goodman C, Cherry G, Cunnington D, KronborglCentral sleep apnea in stable methadone maintenance treatment patients.Chest. 2005 Sept; 128 (3): 1348-1356.PMID: 16162728 [PubMed – indexed for MEDLINE]

Manual CPAP/ASV Titration

Procedure

Effective Date: Supercedes: All Others

Standard Operating Procedure Section ADULT PSG Chapter 4 Page 1 of 1 DEFINITION- Titration with Adaptive Servo Ventilation (ASV) is performed in patients with complex sleep apnea. This includes patients with emergent central apneas or Cheyne Stokes Breathing (CSB) on CPAP therapy. PURPOSE- This titration protocol is designed a.) CONFIRM the diagnosis in patients suspected of having complex apnea, when a diagnosis has not recently been confirmed by CPAP titration study, and b.) provide specific guidelines for proceeding to ASV titration based on response to CPAP titration. POLICIES- The initial portion of this titration study will be performed on CPAP to assure that CPAP alone will not be an adequate treatment for the patient’s sleep-disordered breathing. During the CPAP portion of the study, attempts will be made to adjust CPAP downward (to assure central apneas are not due to excessive CPAP pressure), or upward (if obstructive events are actually present). In patients with persistent central events or CSB, standard ASV titration will be conducted. PROCEDURES I. Order/CMN a. An order or CMN must be accompanied with H&P and previous PSG/Titrations. b. Hook up and preparation as per Adaptive Servo Ventilation (ASV) protocol. After lights out, patient is provided CPAP at “starting pressure” (if not designated on order, begin at 5cm). II. CPAP Titration will be performed first.

a. If central apneas are confirmed (5 in 15 minutes), reduce CPAP in 2cm increments, allowing 15 minutes at each setting.

b. If obstructive events are present, increase CPAP in 2cm increments, allowing 15 minutes at each setting.

c. If Cheyne Stokes breathing is confirmed, continue monitoring x 30 minutes to document the breathing pattern, then change to ASV support.

d. If central apneas persist with reducing CPAP pressure to a level at which obstructive events now occur (> 3 events in 15 minutes), change patient to ASV support.