Transcript srbd-ctc-lecture-12-27-16-ken-he-for-posting

Sleep Related Breathing
Disorders
Ken He, MD
Clinical Instructor, GIM
Hospitalist and Sleep Section, VAPSHCS
With slides adapted from “Sleep Disordered Breathing” by Vishesh Kapur,
MD (Harborview) and “PAP Devices” by Brian Palen, MD (Seattle VA)
Overview of SRBD
Review of case studies
Classification of SRBD
Pathogenesis of SRBD
Select treatment options for SRBD
Inpatient management of SRBD
Case #1
You are called to the bedside by RN to evaluate a
patient with oxygen desaturations during sleep.
You observe intermittent apneas of irregular
durations. No snoring is heard. There are
occasional thoracoabdominal movements
associated with hyperpnea followed by sigh.
Case #1
Chart review notes:
52 yo M with Hx of HTN, DM, and PVD admitted
for non-healing, infected foot ulcer. Amputation
is planned tomorrow. Medications include
lisinopril, insulin, and aspirin.
Focused exam reveal VSS, BMI 33, MM2, SpO2
96%  85%, normal cardiopulmonary exam.
Case #1
What is the most likely diagnosis?
a) Obstructive sleep apnea
b) Central sleep apnea
c) Sleep-related hypoventilation
d) Sleep-related hypoxemia
Breathing Disorders During Sleep
Abnormal
Breathing Rhythm
Obstructive
Sleep Apnea
Central
Sleep Apnea
Abnormal
Gas Exchange
Hypoventilation
Hypoxemia w/o
Hypoventilation
Sleep Related Breathing Disorders
OSA
Upper airway
obstruction
CSA
Unstable Ventilation
Disorders
Disorders
Obstructive
Sleep Apnea
Syndrome
Cheyne-Stokes
Breathing
Opioid-induced
CSA
Hypoventilation
Hypoxemia
Inadequate
Ventilation
Ventilation/
Perfusion
Mismatch & Other
Disorders
Disorders
Neuromuscular
Disease
COPD
Obesity
Obesity
Pulmonary Embolism
Hepatopulmonary
Syndrome
Lung volume
Ventilatory
control
stability
Oropharyngeal
dilator muscle
activity
Craniofacial
anatomy
Sleep state
stability
OSA
Pathogenesis
Rostral fluid
shifts
Screening
STOP-BANG
S = loud snoring
OSA Risk
T = tired/fatigue
O = observed apneas
Low risk = 0-2
P = blood pressure
B = bmi >35
Intermediate risk = 3-4
A = age >50
N = neck >16 inches
G = male (guy)
High risk = 5-8
Case #1
How will you manage this patient?
a) Supplemental oxygen
b) Positive airway pressure
c) Reassure patient and RN
d) Positional therapy
e) Obtain inpatient sleep study
Oxygen
Advantage
• Tolerability
• Improves SpO2
• Superior to placebo
Disadvantage
• Does not affect AHI
severity
• Prolongs respiratory
event duration
• Worsens hypercarbia
• Inferior to CPAP
• Unknown long term
consequences, no
mortality benefit
Positional
Peri-operative
• >80% of OSA undiagnosed at time of surgery
• Increased post-op complications
• Management
– Transient post-op PAP use
– Supplemental oxygen
– Positioning is often limited post-op
– Respiratory therapy assistance
– Pulmonary / Sleep consultation
PAP Devices
Then
Now
The Business
Respironics
ResMed
• Continuous
• Continuous
– CPAP
– Auto-CPAP
– CPAP
– Auto-CPAP
• Bi-level
– Without Backup rate (E0470)
• BiPAP™
• BiPAP Auto
– With Backup rate
(E0471)
• BiPAP S/T
• BiPAP Auto SV Advanced (servo)
• BiPAP Auto S/T with AVAPS
– Average Volume Assured
Pressure Support
• Bi-level
– Without Backup rate
(E0470)
• VPAP™
• VPAP COPD
• VPAP Auto
– With Backup rate
(E0471)
• VPAP ST
• VPAP Adapt SV (servo)
• VPAP ST-A with iVAPS
– Intelligent Volume Assured
Pressure Support
The Business
Respironics
• Continuous
– CPAP
– Auto-CPAP
• Settings
– Minimum 4 cm
– Maximum 20 cm
ResMed
• Continuous
– CPAP
– Auto-CPAP
• Settings
– Minimum 4 cm
– Maximum 20 cm
What is CPAP?
CPAP: Continuous Positive Airway Pressure
Catelleto M et al., Medscape reference
Respironics Auto Titrating CPAP
Event classified as an Obstructed Airway Apnea
CPAP Pressure increased (after 2-OA’s)
No Flow
Response!
Backup Breaths
ResMed Auto Titrating CPAP
Case #1
Discharge Planning?
a) Referral to sleep center
b) Supplemental oxygen for home
c) Setup PAP device
Case #2
You are called to the bedside by spine cord
injury RN to evaluate a patient with low oxygen
saturations during sleep.
You observe a normal respiratory pattern. No
snoring is heard. There appears to be a
associated thoracoabdominal movements
throughout the respiratory cycle.
Case #2
Chart review notes:
38 yo M with Hx of AIS C5 SCI secondary to climbing
injury admitted 2 days ago for his scheduled annual
SCI evaluation. Health is at baseline. Medications
include baclofen, fluoxetine, and prazosin. No hx
lung disease.
Focused exam reveal VSS. BMI 28, MM2, SpO2
87%, normal cardiopulmonary exam, trace
dependent edema. Your MS-3 counts RR of 26.
Case #2
What is the most likely diagnosis?
a) Obstructive sleep apnea
b) Central sleep apnea
c) Sleep-related hypoventilation
d) Sleep-related hypoxemia
Sleep Related Breathing Disorders
OSA
Upper airway
obstruction
CSA
Unstable Ventilation
Disorders
Disorders
Obstructive
Sleep Apnea
Syndrome
Cheyne-Stokes
Breathing
Opioid-induced
CSA
Hypoventilation
Hypoxemia
Inadequate
Ventilation
Ventilation/
Perfusion
Mismatch & Other
Disorders
Disorders
Neuromuscular
Disease
COPD
Obesity
Obesity
Pulmonary Embolism
Hepatopulmonary
Syndrome
Hypoventilation
Inadequate ventilation
to maintain a normal
PaCO2
Normal values:
V E = VT x f
Awake 35-45
mm Hg
Awake
hypoventilation
: > 45 mmHg
NREM = Awake
+ 3-7 mm Hg
REM = Awake +
5-9 mm Hg
Hypoventilation
• AASM definition for adult sleep-related
hypoventilation:
– PaCO2 (or validated surrogate) > 55 mmHg for ≥ 10
minutes OR
– PaCO2 ≥ 10 mmHg during sleep compared to awake
supine value and > 50 mmHg for ≥ 10 minutes.
• Surrogates
– End-tidal PCO2 (ETCO2)
– Transcutaneous PCO2 (TCCO2)
End Tidal CO2
• Measures alveolar CO2
• 2-5 mm Hg lower than PaCO2
• difference when there is dead space
– Sleep
– COPD
– Severe obesity
– Pulmonary embolism
End Tidal CO2
• Requires assessment of
a wave form plateau
• Not always technically
feasible with ongoing
respiratory therapy
Transcutaneous CO2
• TCCO2 measures capillary CO2
• Technology improved
– Less heat
– No need to reposition sensor
• Not prone to some pitfalls of
ETCO2
– Lung disease
– During PAP therapy
Hypoventilation Pathogenesis
Increased work
• Increased upper airway
resistance
• Increased thoracic mass
WON’T
BREATHE
Reset of respiratory
chemostat
Decreased ability to
ventilate in sleep
• Renal bicarbonate retention
• Diminished muscle tone
• Loss of chest/lung compliance
Decreased respiratory
drive
• Decreased ventilatory
response to CO2 and O2
CAN’T
BREATHE
Case #2
How will you manage this patient?
a) Supplemental oxygen
b) Positive airway pressure
c) Reassure patient and RN
d) Positional therapy
e) Obtain inpatient sleep study
Case #2
Further daytime testing reveals:
• Semi-recumbent awake SpO2 95%
• ABG pH 7.36, PaCO2 45
• Bedside spirometry
– FEV1 2 liters, 45% of predicted
– FVC 2.5 liters, 40% of predicted
– MEP +100, MIP -40
Treatment
• Increase ventilation by providing pressure
and/or rate support
– Bi-level PAP (S mode, no backup rate)
– Bi-level PAP (ST mode, with backup rate)
– Average/Intelligent Volume Assured Pressure
Support (AVAPS/iVAPS)
• Positional
– Use gravity to improve lung expansion
CPAP and Bi-Level
IPAP
EPAP
Pressure Support
Window
CPAP
IPAP: Inspiratory Positive Airway Pressure
EPAP: Expiratory Positive Airway Pressure
Bi-Level
Respironics
• Without Backup rate (E0470)
– BiPAP™
– BiPAP Auto
• With Backup rate
ResMed
• Without Backup rate (E0470)
– VPAP™
– VPAP COPD
– VPAP Auto
(E0471)
– BiPAP ST
– BiPAP Auto SV Advanced (servo)
– BiPAP AVAPS
• Average Volume Assured
Pressure Support
• With Backup rate
(E0471)
– VPAP ST
– VPAP Adapt SV (servo)
– VPAP ST-A with iVAPS
• Intelligent Volume Assured
Pressure Support
Bi-Level
Respironics
• Without Backup rate (E0470)
– BiPAP™
– BiPAP Auto
• With Backup rate
(E0471)
– BiPAP ST
• Settings
– Minimum EPAP 4 cm
– Maximum IPAP 25 cm
– PS variable, not fixed
ResMed
• Without Backup rate (E0470)
– VPAP™
– VPAP COPD
– VPAP Auto
• With Backup rate
(E0471)
– VPAP ST
• Settings
– Minimum EPAP 4 cm
– Maximum IPAP 25 cm
– PS variable, fixed
Standard Bi-Level
Indications
• OSA
– High pressure requirements
– Comfort
• Hypoventilation
Contraindications
• CSA
– Must have a backup rate
 Modes: CPAP, S
(spontaneous)
 ResMed VPAP
•Trigger/cycle sensitivity
•Ti Control:
Insp Time min/max ,
Rise Time
 Respironics BIPAP
•Bi-Flex
•Rise Time
Auto titrating Bi-Level
Indications
Contraindications
• OSA
• CSA
• ? Hypoventilation
– High pressure requirements
– Comfort
•ResMed VPAP
•Titrates with a fixed pressure support window (that you set) by adjusting EPAP
based on obstructive events
•Respironics BiPAP
•Titrates EPAP based on obstructive apneas and snoring
•Titrates IPAP based on hypopneas and air flow limitation(s)
Bi-Level ST (backup rate)
Respironics
• BiPAP ST
– Modes: CPAP, S, ST, PC, T
ResMed
• VPAP ST
– Modes: CPAP, S, ST, T
• Does NOT auto titrate
• Indications:
•
•
•
CSA
Hypoventilation
Intolerance or poor response to
ASV or VAPS
Case #2: Discharge Planning
a) Referral to sleep center
b) Supplemental oxygen for home
c) Setup PAP device
Device Qualification
COPD
Restrictive
•
•
•
E0470 (BPAP S)
– ABG (PaCO2 > 52 mmHg – Awake
on prescribed FiO2) &
– Nocturnal Oximetry (SpO2 ≤ 88%
≥ 5 min – on 2lpm or prescribed
FiO2) &
– OSA (has been considered and
ruled out)
E0471 (BPAP ST)
– After use of E0470
• ABG shows PaCO2 ≥ 52 or
change ≥ 7 mm Hg
• PSG or Noc oximetry on
E0470 shows SpO2 ≤ 88% ≥ 5
min
E0470 or E0471 (per tx MD)
– Neuromuscular condition or
Thoracic cage abnormality and 1
of the following:
• ABG (PaCO2 > 45 mmHg )
– Awake on prescribed
FiO2
• Nocturnal Oximetry
– (SpO2 > 88% ≥ 5 min –
on prescribed FiO2)
• For Neuromuscular dz only:
– MIP (< 60 cmH2O) or
– FVC (< 50% predicted)
Device Qualification
Central
Hypoventilation
•
•
E0470
– ABG (PaCO2 > 45 mmHg – Awake on
prescribed FiO2) &
– Spirometry (no evidence of obstructive
process) & either:
– ABG (during sleep or immed upon
awakening)
• PaCO2 worsened ≥ 7 mm Hg OR
– Oximetry demonstrates SpO2 ≤ 88% ≥ 5
min not caused by OSA
•
E0471 (After use of E0470), either:
– Awake PaCO2 worsened ≥ 7 mm Hg OR
– Oximetry demonstrates SpO2 ≤ 88% ≥ 5
min not caused by OSA &
– Spirometry shows no evidence of
obstruction
E0470 or E0471 (per tx MD)
– Diagnosis of CSA via full
attended PSG
Case #3
You are called to the bedside by RN to evaluate a
patient with oxygen desaturations during sleep.
You observe intermittent apneas of regular
durations. No snoring is heard. There appears
to be a rhythmic pattern of thoracoabdominal
movements followed by no movement.
Case #3
Chart review notes:
71 yo M with Hx of HFrEF 35%, pAfib, and CKD
admitted for worsening dyspnea on exertion,
weight gain, and orthopnea. IV diuresis is ongoing.
Medications include lisinopril, carvedilol,
spironolactone, furosemide, and warfarin.
Focused exam reveal HR 100 irregular, BP 95/68, RR
22, BMI 33, MM3, SpO2 96%  91%, JVD, S3,
bilateral rales, leg edema.
Case #3
What is the most likely diagnosis?
a) Obstructive sleep apnea
b) Central sleep apnea
c) Sleep-related hypoventilation
d) Sleep-related hypoxemia
Sleep Related Breathing Disorders
OSA
Upper airway
obstruction
CSA
Unstable Ventilation
Disorders
Disorders
Obstructive
Sleep Apnea
Syndrome
Cheyne-Stokes
Breathing
Opioid-induced
CSA
Hypoventilation
Hypoxemia
Inadequate
Ventilation
Ventilation/
Perfusion
Mismatch & Other
Disorders
Disorders
Neuromuscular
Disease
COPD
Obesity
Obesity
Pulmonary Embolism
Hepatopulmonary
Syndrome
Central Sleep Apnea
Unstable ventilation
High Loop Gain
Cheyne Stokes
Breathing
Brainstem
Dysfunction
Opioid-induced
Sleep Apnea
High Loop Gain CSA:
What is Cheyne Stokes Breathing?
CSB Patient Diagnostic Study
6 minute screen, each block is 30 seconds
Ventilatory Control
• During wake
– All systems engaged
Behavioral
pH
Control of
Breathing
PaO2
PaCO2
Ventilatory Control
• During sleep
– Loss of behavioral control
– Increased apneic
threshold
PaCO2
• PaCO2 level below which
breathing stops
Control of
Breathing
pH
– Loss of wakefulness drive
• PaCO2 level rises with sleep
PaO2
– Decreased
chemosensitivity
Ventilatory Instability
• PaCO2 regulated by automated negative feedback control
• Central apneas occur when PaCO2 is below apneic
threshold
– More likely when average PaCO2 is close to the apneic
threshold
Loop Gain
• The measure of the propensity of a negative feedback
control system to oscillate
• Disturbance  Ventilatory Control System  Response
(e.g. hypopnea/apnea)
(e.g. hyperpnea)
• Loop Gain = Response/Disturbance
• Increased feedback for input (high loop gain) leads to
unstable ventilation and PaCO2 levels
Dempsey JA, J Physiol 2004
White DP, AJRCCM 2005
White DP, Orlando 2005
Unstable Temperature Control
Unstable Ventilatory Control
Central Sleep Apnea
Unstable ventilation
High Loop Gain
Cheyne Stokes
Breathing
Brainstem
dysfunction
Opioid-induced
Sleep Apnea
Sleep & Breathing During Opioid Use
Sleep & Breathing
During Opioid Use
Opioids
Ataxic breathing & bradypnea (150 second screen)
Opioid related Sleep Apnea
• Effects on rhythm
generators in medulla
– Opiate sensitive neurons
– Pre-Botzinger complex
• Prevalence
– 30% of patients on
methadone
maintenance
– 70% of sleep clinic
patients on chronic
opioids
– Dose dependent
Wang et al. Chest 2005; 128:1348-1356.
Walker JM et al. J Clin Sleep Med 2007; 3(5): 455-61.
Case #3
How will you manage this patient?
a) Supplemental oxygen
b) Positive airway pressure
c) Reassure patient and RN
d) Positional therapy
e) Treat the underlying disorder
f) Obtain inpatient sleep study
CSB Therapy
• Goal is to reduce loop gain
– Heart failure therapy
– CPAP
– Adaptive servo-ventilation
– Oxygen
– Avoidance of supine position
– Promote REM sleep
Servo Ventilation
Servo Mechanism: A device used to control a desired
operation via the use of feedback.
What is ASV?
• Adaptive Servo Ventilation
• Variable bi-level or pressure support device
– Base pressure 8/5
– Adjusts pressure support to supplement ventilation when
decreases to <90% of average ventilation
– Initiates breath if no effort
Airflow
VPAP Adapt SV
(ASV on)
RESMED
Respironics BIPAP Auto SV Advanced
Servo Ventilation Algorithm
4 Minutes
On a breath by breath basis peak flow is captured
Peak flow is monitored over a moving 4 minute window
As 1 breath is added, the initial breath falls off
At every point w/in this 4 minute period an Average Peak Flow is calculated
The Peak flow target = 95% peak flow average
Slide courtesy of Respironics
Respironics BiPAP Auto SV Advanced
Servo Ventilation Algorithm – Decreased Flow
IF: Peak flow falls below target
THEN: autoSV increases pressure support
Slide courtesy of Respironics
Servo Ventilation
Indications
Contraindications
• Periodic Breathing
• Hypoventilation
• Heart failure with reduced
ejection fraction ≤ 45%
– Cheyne-Stokes
• Central Sleep Apnea
– Idiopathic
– Medication
– Neurologic
• Treatment Emergent Central
Sleep Apnea
Servo Ventilation
Respironics
• Without Backup rate
(E0470)
(E0470)
– VPAP™
– VPAP COPD
– VPAP Auto
– BiPAP™
– BiPAP Auto
• With Backup rate
ResMed
• Without Backup rate
• With Backup rate
(E0471)
– BiPAP ST
– BiPAP Auto SV Advanced (servo)
– BiPAP AVAPS
• Average Volume Assured
Pressure Support
–
–
–
–
(E0471)
VPAP ST
VPAP Adapt SV (servo)
Auto VPAP Adapt SV
VPAP ST-A with iVAPS
• Intelligent Volume Assured
Pressure Support
Baseline
CPAP 20
Adapt SV
EEP 5
PS min 3, max 15
Adapt SV
EEP 9
PS min 7, max 15
Case #3: Discharge Planning
a) Referral to sleep center
b) Supplemental oxygen for home
c) Setup PAP device
Sleep Related Breathing Disorders
OSA
Upper airway
obstruction
CSA
Unstable Ventilation
Disorders
Disorders
Obstructive
Sleep Apnea
Syndrome
Cheyne-Stokes
Breathing
Opioid-induced
CSA
Hypoventilation
Hypoxemia
Inadequate
Ventilation
Ventilation/
Perfusion
Mismatch & Other
Disorders
Disorders
Neuromuscular
Disease
COPD
Obesity
Obesity
Pulmonary Embolism
Hepatopulmonary
Syndrome
Hypoxemia
Etiology
Treatment
Ventilation
perfusion mismatch
Treat underlying
disorder
Hypoventilation
Oxygen
Right to left shunt
PAP therapy
Altitude / low
ambient O2
Diffusion limitation
CSA
Opioids
CHF
OSA
COPD
Hypoventilation
Other Hypoxemia
Putting it All Together
OSA
CSA
Hypoventilation
Overlap Synd.
CPAP
Auto CPAP
Bi-Level
Treatment
emergent
CSA?
Servo
Ventilation
Bi-Level
Volume Assured
Pressure
Support
Limitations of Loaner PAP
• Inaccurate settings
• Advanced modes NOT available
• Decreased comfort level
– PAP delivery algorithm may vary
– Mask fit
• Device availability
Key Points
• SRBD takes on various forms
• Management of SRBD is not always
straightforward
• PAP modalities have different indications /
limitations
• Inpatient sleep studies are challenging
• Inpatient device setups may be limited by RT
knowledge
Inpatient Evaluation Algorithm
PAP Type
Indicated
Contra-indicated
CPAP
OSA
CSA
Auto titrating CPAP
OSA
CSA
Hypoventilation
Bi-Level
OSA
Hypoventilation
CSA
Bi-Level with rate
Hypoventilation
CSA
Auto titrating Bi-Level
OSA
Hypoventilation
CSA
Servo Ventilation
CSA
Hypoventilation
Volume Assured Pressure
Support
Hypoventilation
Overlap Syndrome