Ventilation et RCP de l’arrêt cardiaque:

Jean-Christophe M Richard

Pôle SAMU 74 Urgence et Réanimation Centre Hospitalier Annecy Genevois

INSERM UMR 955 Eq13 Créteil

CONFLICTS OF INTEREST

- Air Liquide Medical Systems (part time)

Financial support for research (Genève /Annecy/Angers)

- VYGON (personal fee for lectures)

- SHILLER

- MAQUET (NAVA)

- COVIDIEN (PAV+) (personal fee for lectures)

- DRAGER (SmartCare)

- GE (FRC)

Comment la ventilation est faite peandant la RCP?

Manual Bag ventilation and 30:2 Chest Compression ratio

1328 questionnaires / 545 complétés

Compressions seulement pendant les premiers secours: (29.6%)

Interruption des compressions pendant l’intubation : (48%)

Interruption des compressions pour ventiler après intubation : (18%)

Risques associés à la ventilation au Bag Mask

JAMA 2005

Risques associés: hyper ventilation

The Lazarus phenomenon refers to a ROSC that occurs after ventilation interruption.

The Lazarus phenomenon is the moststraight full illustration of the riskassociated with hyperventilationduring CPR.

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ICC 30:2

Vti (L)

Vte (L)

Gastric inflation (L)

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CCC 10/min

Vti (L)

Vte (L)

Gastric inflation (L)

30 insuflations 30 insuflations 60 insuflations

Ventilation & gastric inflation

N=5 cadavers

Standard deviations

Vti = 0,111

Vte = 0,165

Gastric Inflation = 2,3

Standard deviations

Vti = 0,099

Vte = 0,142

Gastric Inflation = 1,25

Standard deviations

Vti = 0,109

Vte = 0,103

Gastric Inflation = 1,170

Vt expiré : 319±165 ml (ICC 30:2) 341±142 ml (CCC 30:2) 277±103 ml (CCC 10/min)

Circulation Ventilation

Continuous Chest Compression strategy

Mécanisme des compressions thoraciques (CT)

• ETI + curarised subjects → Manual CC generates 156mL of VT (0 to 390mL)

• ETT + cardiac arrest subjects →Manual CC generates no VT

The median Vt per compression : 41.5 ml (33.0-62.1 ml) which was considerably less than measured dead space

ml

a

bc

d

e f

a. Ressort

b. Soufflet

c. Seringue

d. Prise de pression

dans le soufflet

e. Entré d’air

f. Stylet et Papier

millimétrique

f

Pressure transmitted into the

thoracic compartment

Change in lung volume: Vt and FRC

FRC

Reduction in lung volume below FRC induced by Chest compressionsF

low

P

aw

V

olu

me

Lung volume reduction below FRC

FRC

Cordioli et al. J Appl Physiol 2016

Flow limitation at PEEP 0

PEEP 3 cmH20 PEEP 0 cmH20

Lung airways closure limiting inspiratory flow during Chest compressions

Cordioli et al. J Appl Physiol 2016

For similar chest compressions, thoracic airways closure limits both Paw transmission and ventilation….

As results, thoracic airways closure may affect capnogram and therefore be informative regarding ventilation ….

ERC Guidelines 2015 on EtCO2 monitoring

1. To check proper placement of tracheal tube

2. To monitor respiratory rate to avoid hyperventilation

3. To assess quality of chest compressions

4. To detect ROSC without interrupting chest compressions

5. To predict outcome at 20 min

“Our Lack of confidence in the accuracy of EtCO2 measurement during CPR, and the need of

advance airway to measure EtCO2 reliably, limits our confidence in its use for prognostication” ….

EtCO2 depends on CO2 circulation but also on Ventilation !

Because EtCO2 oscillates according to chest compressions but also periodically according to ventilation we

hypothesized that the phenomenon of “thoracic airways closure” could affect capnogram….

Accidental observation: Periodic variation of EtCO2 during CPR

Capnogram (EtCO2 waveform) during CPR may varies periodically with chest compressions and ventilation….

EtCO2 recordings in OHCA versus TC Lung Model

EtCO2 recordings in OHCA versus TC Lung Model

Leturiondo M et al. Resuscitation 2018

CO

2

Time (s)CO

2 P

rod

uct

ion

L/m

in

ROSC

Methods 1: Bench model with CO2 (Toronto Lab)

D Luca Grieco, et al. (manuscript in preparation)

Insufflation from the

ventilator

Alveolar CO2 CO2 Wash out by fresh gas

Results 2: Bench model with CO2 (Toronto Lab)

How to interpret EtCO2 oscillating or non-oscillating pattern ?

CO

2

Airways opening measurements

P-P

aw

CO

2

ITP

CO

2

Intra thoracic measurements

D Luca Grieco, et al. (manuscript in preparation)

Methods 2: Thiel cadaver model with CO2 (CAVIAR lab)

D Luca Grieco, et al. (manuscript in preparation)

Results 3: Thiel cadaver model with CO2 (CAVIAR lab)

Airway transmission

P-P

aw

CO

2

Human cadaver recordings

Airway closure

CLINICAL OBSERVATIONAL STUDY : 100 OHCA patients:

Results 5: Clinical observations (Annecy Hospital)

D Luca Grieco, et al. (submitted)

What EtCO2 patterns teach us about ventilation quality ?

Results 6: Clinical observations (Annecy Hospital)

D Luca Grieco, et al. (manuscript in preparation)

Which EtCO2 value is the best surrogate of alveolar CO2 ?

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25

50

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100

Patients

CO

2 (

mm

Hg

)

OHCA

N=90 Patients

CLINICAL OBSERVATIONAL STUDY : 100 OHCA patients:

EtCO2 values collected in 1 capnogram for each patient

CLINICAL OBSERVATIONAL STUDY : 100 OHCA patients:

Results 5: Clinical observations (Annecy Hospital)

D Luca Grieco, et al. (submitted)

What EtCO2 patterns teach us about ventilation quality ?

Figure 3.R1

Figure 5.R1

CPV : Cardio Pulmonary Ventilation ( Monnal T60 )

4 paramètres pour guider la RCP

• fCT, la fréquence des compressions thoraciques

• % CT, le % de compressions thoraciques continue (fraction CPR)

• P-P, Feed back sur la force des compressions thoraciques

• CO2, EtCO2 expiré max

SU

RV

IVA

L

TIME

Brain perfusion guided therapy

4 7 10

Airway Closure? guided therapy

ETCO2 guided therapy

Annecy CPR Round Table :Two phase time sensitive model to OHCA

High Quality CPREarly Defibrillation

Cardiac Pump

Goal Directed OptimizationCardiac and Thoracic Pump

Consider ECMO

CONCLUSIONS

• La ventilation pendant la RCP doit être revisitée pour en limiter les effets délétères circulatoires.

• Favoriser les CT continues doit être une prioritaire.

• La ventilation pendant la RCP est nécessaire car la fermetures des petites voies aériennes intra

thoracique limite la ventilation liée aux simples CT.

• Des outils de monitoring de l’EtCO2 spécifiquement adaptés à la RCP sont nécessaire pour la

pratique

• La valeur maximum d’EtCO2 est celle qui reflèterait le mieux le CO2 alvéolaire et l’état circulatoire

• L’analyse des variations d’EtCO2 pourrait aussi renseigner sur la qualité de la ventilation