Home NIV: Aims and Targets
Dan Adler, St.Gallen 2012
Aims of home NIV are:
 To improve QoL and symptoms related to hypercapnia (questionnaires)
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To improve nocturnal SpO2 and correct nocturnal hypoventilation
(nocturnal SpO2/PtCO2)
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To ensure that leaks are minimal, and estimated VE is adequate (What
information can we get from built-in softwares? Can we trust this
information?)
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To improve quality of sleep (Do we really need PSG during NIV? Is there a
surrogate marker for inspiratory effort and for cortical arousal?)
Why should we monitor NIV during sleep?
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Patients on HMV admitted (yearly) to monitor NIV.
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20 OHS patients in stable condition admitted to monitor NIV
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55% with PVA
40% with periodic breathing under NIV
48 patients admitted for a scheduled control in a phase of clinical
stability.
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41/53 patients presented any abnormality (leaks, desaturation dips or
continuous desaturation)
No IE during day NIV trial/ IE very frequent finding during sleep
30 COPD patients in stable condition (no overlap syndrome), ~1/3
patients complained of severe dyspnea immediately after
interruption of NIV in the morning.
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PVA found in all patients using PSG and subjective improvement of sleep
quality after setting NIV with a predefined approach
Rabec, ERJ 2009; Guo Chest 2007; Fanfulla Respiratory Medicine 2007; Adler Sleep and Breathing 2011
Presentation outline:
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Basic Monitoring
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PG/PSG
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SRI Questionnaire+ “Geneva” Questionnaire
SpO2/PtCO2 monitoring
Built-in software
Respiratory events classification
Setting NIV using PSG
When should you organize a PG/PSG under NIV?
New Tools:
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PTT (pulse transit time)
PWA (pulse wave amplitude)
SRI: The Severe Respiratory Insufficiency
Questionnaire

SRI questionnaire: Disease
specific measure of health-related
quality of life in patients receiving
HMV.
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Windisch W, J Clin Epidemiol
2003;56:752
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English Version
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French Version: www.isplf.org
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8 domains: respiratory complaints,
social functioning, sleep, anxiety,
social relationships, well-being and
physical functioning+ SRI summary
scale
Windisch, Breath 2011
NIV has a major impact on HRQL
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N= 137 patients: COPD, restrictive disease, OHS, NMD
SRI tot
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SF36 physical
SF36 mental
SRI is more sensitive than SF36 to detect HRQL
changes in this specific population
Windisch, ERJ 2008
SRI too long for routine clinical practice?
Windisch, ERJ 2008
If NIV is intended to improve sleep, we should aim at
maximal comfort during the night
8 item VAS assessing sleep, comfort, perception of synchronisation, airflow, leaks,
noise.
Janssens, Respir Med, 2008; Adler Sleep and Breathing 2011
Basic Monitoring: SpO2 monitoring is
certainly not enough during NIV
Desaturation drops
Sustained desaturation > 10min
Both patterns are non-specific for the underlying mechanism leading to desaturation
Janssens, Thorax 2010
Poor correlation between diurnal PaCO2
and mean nocturnal PtCO2
Sn= 3/(3+18)= 14.3%
Paiva, ICM 2009
Normal values of nocturnal oximetry do not allow to
exclude nocturnal hypoventilation
Nocturnal SpO2 is not a
surrogate marker of PCO2
CO2
60
CO2
35
2012 JIVD abstracts: Lamia and Muir, Niguyen-Baranoff and Rabec
Transcutaneous CO2 monitoring can
replace arterial PCO2 during NIV
3 modern PtCO2 monitor were compared
After correction of the technical drift
Storre, Respir Med, 2011
Transcutaneous CO2 monitoring can
replace arterial PCO2 during NIV
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Gazométrie
Gazométrie
Gazométrie
Gazométrie
PtCO2 adequately
reflects PaCO2
during NIV
Advantages:
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Non-invasive
No sleep disruption
Continuous
Storre, Respir Med, 2011
Built-in Software: What can we trust?
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Many recent home
ventilators have built-in
software which allows
monitoring of items such
as:
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Compliance
Leaks
Vt, MV, RR
% of triggered cycles
% of spontaneous
expiration ( cycling)
AHI
Pasquina, Respiration 2012
Built-in Software +
Monitoring system
Normal
Leaks
Hypoventilation?
Residual obstructive
events? PB ?
Rabec. ERJ 2009
Built-in software: Validation of leaks and
MV on a bench test
R=0.947
P<0.001
R=0.959
P<0.0001
Bias: 0.7 L/min, not relevent!
Rabec, ERJ 2009
Built-in software: Leaks in a non hermetic
system are intentional.
What are we talking about?
Total leak mesured
Total leak mesured
Leak above
“intentional ones”
Contal, Chest 2012
Built-in software: Software estimation vs
mesured leaks on a bench test.
. “All ventilators are equal but some ventilators are more equal than others…”
Only 3 ventilators had narrow limits of concordance!
Contal, Chest 2012
Built-in software: Vt software estimation vs
mesured Vt
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For most
ventilators,Vt is
underestimated
Underestimation
is worst with
higher pressures
Vt estimation is
little affected by
leaks
Contal, Chest 2012
Built-in software: Is set pressure reliable?
A= Effective PT product
S= Surface of ideal PTP
A/S ratio
A
Battisti, Chest 2005
Wide differences between pressurization
capatilities in home ventilators
Battisti, Chest 2005
Low % of spontaneous inspirations in very
severe COPD Ineffective efforts?
RR 14/ min
Neural RR
24/min
Correction of IE using PSG to set NIV
Neural RR=
Effective RR
Adler, Sleep and breathing 2011
Built-in Software: Summary
Daily/Weekly/etc… use
--
Respiratory rate
Accurate
Leaks
Accurate only in some ventilators
Vt
Underestimation of Vt in most
ventilators
Pressure
Wide variations in pressurization
capabilities. Knowledge of the technical
performance of your device is essential!
http://www.antadir.com/fr/professionnel
AHI
No validation. In progress…
% Triggered cycles
No formal validation. Usefull in clinical
pratice (controlled vs spontaneous
ventilation).
% of spontaneous expiration
No formal validation.
The final touch…
Janssens, Thorax 2010
Leaks
Gonzalez-Bermejo, Thorax 2010
Upper airways closure
“central”
“Obstructive”
Gonzalez-Bermejo, Thorax 2010
PB under NIV
Gonzalez-Bermejo, Thorax 2010
Use PSG+SpO2/PtCO2 to adapt NIV
settings
Type d’asynchronies identifiées
Modification du paramétrage proposée
Apnées ou hypopnées obstructives
Augmentation de l’EPAP ou si mauvaise tolérance
augmentation de la FR
Hypoventilation
Augmentation de l’aide inspiratoire et/ou augmentation
de la FR back-up
Respiration périodique
Baisse de l’aide inspiratoire si normocapnie (ASV?) ou
augmentation de la FR si hypercapnie
Auto-déclenchement
Corriger la fuite et éventuelle modification du
trigger inspiratoire
Double-déclenchement
Augmentation du temps inspiratoire ou de l’aide
inspiratoire
Effort non-récompensé
Correction de l’air-trapping: diminution de l’aide
inspiratoire, augmentation du trigger expiratoire et
éventuellement augmentation de la PEEP ou high
BURR
Pente de pressuriation concave
Augmentation de la pente de pressurisation
Adler, Sleep and Breathing 2011
New tools for NIV monitoring at home?
PTT: Pulse Transit Time
PWA: Pulse Wave Amplitude
Basic knowledge: PTT changes with
intrathoracic pressure swings
Basic knowledge: PWA reduction is a
surrogate marker of cortical arousal in
healthy subjects and in OSA
PTT: Smith ,Thorax, 1999 PWA: Delessert, Sleep 2010
Obstructive or central event?
Luo, Chest 2009
PTT as a marker of inspiratory effort during
NIV
Contal , ERJ 2012
PTT as effective as Peso for classification of
respiratory events during NIV
Contal, ERJ 2012
Pulse Wave Amplitude Reduction: A
surrogate marker of EEG-MA during NIV?
EOG
A
B
EEG
Chin
Pressure
Flow
Thx & Abd
mvt
SpO2
PWA
Adler, submitted
PWA Sn and PPV to detect EEG-MA related
to respiratory events during NIV
2474 respiratory events under NIV were analysed in 10 patients.
Sensitivity 89.1% and PPV 87% to detect EEG-arousal related to a respiratory
event under NIV
Adler, submitted
Home NIV: Aims and Targets
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HRQOL.
 SRI questionnaire
Nocturnal PtCO2 monitoring is mandatory.
 Diurnal ABG is not a surrogate marker
 Nocturnal SpO2 is not a good surrogate marker
Trust your built-in software only if it has been independently validated.
Use of PG/PSG only in special situations. In this case, take advantage of the
sleep study to adapt the NIV settings while the patient is asleep.
New ambulatory tools may be available in a near future.
 PWA is a surrogate marker of arousal related to respiratory events
under NIV
 PTT for classification between central and obstructive respiratory events
under NIV