Home NIV: Aims and Targets

Dan Adler, St.Gallen 2012

Aims of home NIV are:

To improve QoL and symptoms related to hypercapnia

(questionnaires)

To improve nocturnal SpO2 and correct nocturnal

hypoventilation (nocturnal SpO2/PtCO2)

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?)

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?

Patients on HMV admitted (yearly) to monitor NIV. 41/53 patients presented any abnormality (leaks, desaturation dips

or continuous desaturation) 20 OHS patients in stable condition admitted to monitor NIV

55% with PVA 40% with periodic breathing under NIV

48 patients admitted for a scheduled control in a phase of clinical stability. 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. 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:

Basic Monitoring SRI Questionnaire+ “Geneva” Questionnaire SpO2/PtCO2 monitoring Built-in software

PG/PSG Respiratory events classification Setting NIV using PSG When should you organize a PG/PSG under NIV?

New Tools: 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. Windisch W, J Clin Epidemiol

2003;56:752

English Version

French Version: www.isplf.org

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 N= 137 patients: COPD, restrictive disease,

OHS, NMD

SRI is more sensitive than SF36 to detect HRQL changes in this specific population

SRI totSF36

physicalSF36 mental

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

Janssens, Respir Med, 2008; Adler Sleep and Breathing 2011

8 item VAS assessing sleep, comfort, perception of synchronisation, airflow, leaks, noise.

Basic Monitoring: SpO2 monitoring is certainly not enough during NIV

Desaturation dropsSustained desaturation > 10min

Janssens, Thorax 2010

Both patterns are non-specific for the underlying mechanism leading to desaturation

Poor correlation between diurnal PaCO2 and mean nocturnal PtCO2

Paiva, ICM 2009

Sn= 3/(3+18)= 14.3%

Normal values of nocturnal oximetry do not allow to exclude nocturnal hypoventilation

CO2 35

CO2 60

2012 JIVD abstracts: Lamia and Muir, Niguyen-Baranoff and Rabec

Nocturnal SpO2 is not a surrogate marker of PCO2

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

PtCO2 adequately reflects PaCO2 during NIV

Advantages: Non-invasive No sleep

disruption Continuous

Storre, Respir Med, 2011

GazométrieGazométrie

Gazométrie

Gazométrie

Built-in Software: What can we trust? Many recent home

ventilators have built-in software which allows monitoring of items such as: Compliance Leaks Vt, MV, RR % of triggered cycles % of spontaneous

expiration ( cycling) AHI

Pasquina, Respiration 2012

Built-in Software + Monitoring system

Rabec. ERJ 2009

Normal Leaks

Hypoventilation?

Residual obstructive

events? PB ?

Built-in software: Validation of leaks and MV on a bench test

Rabec, ERJ 2009

R=0.947P<0.001

R=0.959P<0.0001

Bias: 0.7 L/min, not relevent!

Built-in software: Leaks in a non hermetic system are intentional.

Contal, Chest 2012

Total leak mesured

Total leak mesured

Leak above“intentional ones”

What are we talking about?

Built-in software: Software estimation vs mesured leaks on a bench test.

Contal, Chest 2012

Only 3 ventilators had narrow limits of concordance!

. “All ventilators are equal but some ventilators are more equal than others…”

Built-in software: Vt software estimation vs mesured Vt

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?

Battisti, Chest 2005

A= Effective PT product S= Surface of ideal PTP

A

A/S ratio

Wide differences between pressurization capatilities in home ventilators

Battisti, Chest 2005

Low % of spontaneous inspirations in very severe COPD Ineffective efforts?

Neural RR24/min

RR 14/ min

Correction of IE using PSG to set NIV

Neural RR=Effective RR

Adler, Sleep and breathing 2011

Built-in Software: SummaryDaily/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

PTT: Smith ,Thorax, 1999 PWA: Delessert, Sleep 2010

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

Obstructive or central event?

Luo, Chest 2009

PTT as a marker of inspiratory effort during NIV

Contal , ERJ 2012

PTT mirror

image of Poeso

PTT as effective as Peso for classification of respiratory events during NIV

Contal, ERJ 2012

EOG

EEG

Chin

Pressure

Flow

Thx & Abdmvt

SpO2

PWA

A B

Pulse Wave Amplitude Reduction: A surrogate marker of EEG-MA during NIV?

Adler, submitted

PWA Sn and PPV to detect EEG-MA related to respiratory events during NIV

Adler, submitted

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

Home NIV: Aims and Targets 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