automated modes of ventilation: superior to traditionnal modes ? françois lellouche, md, phd
TRANSCRIPT
AUTOMATED MODES OF VENTILATION: SUPERIOR TO TRADITIONNAL MODES ?
François LELLOUCHE, MD, PhD
CONFLICTS OF INTEREST
- Research contracts with Drager medical
(travel expenses for the Canadian study on SmartCare)
- Research contracts with Hamilton medical to conduct Intellivent evaluation
(Salary of the research assistant)
- Program of research on automated ventilation and oxygen therapy:
Canadian for Innovation(Fonds des Leaders)/FRSQ grants
- President of a R&D compagny that develops automated systems for oxygen therapy
and mechanical ventilation
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Age pyramid US: 1950-2050
Millions of people
♀♂
Why automated modes are required ?
…. To the firstbaby-boomers !!
Angus JAMA 2000
patients on MV
Number of clinicians
Age PyramidComorbidities
Needham CCM 2005
Increasing number of patients with prolonged MV (> 96 hours)
Cost of MV : 16 billions of $/per year in 2003 60 billions of $/per year in 2020 (projection) Zilberberg, CCM 2008
0
100 000
200 000
300 000
400 000
500 000
600 000
700 000
n pa
tien
ts
2000 2020
0
2
4
6
8
10
12
14
16
18
Days of MV * I CU LOS * Hospital LOS *
Mill
ions
of
days
2000 2020
Prolongedmechanical ventilat ion
252.577
605.898
1.5
3.8
2.3
5.86.6
16.7
Data for USA
Failure of the knowledge transfertWeaning/protective ventilatory strategy
Rubbenfeld Respiratory Care 2004
Vilar Acta Anesthesiol Scand 2004
Scale Crit Care Med 2008
Why automated modes are required ?
…. To the firstbaby-boomers !!
ARMA Study6 vs 12 ml/Kg of PBW
FAILURE TO IMPLEMENT KNOWLEDGE
CHALLENGES FOR HEALTH CARE SYSTEM
AUTOMATED SYSTEMS
Mandatory Minute Ventilation
Evita (Dräger) Hewlett Anesthesia 1977
Automode Servo (Maquet) Holdt Resp Care 2001
ASV G5 (Hamilton) Laubscher IEEE Biomed Eng 1994
SmartCare Evita XL, V500 (Dräger) Dojat Int J Clin Monit 1992
ASV Intellivent G5 (Hamilton) Brunner 2002
COMMERCIALLY AVAILABLE AUTOMATED MODES
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Weaning protocols are efficient (Ely NEJM 1996, Saura ICM 1996, Kollef CCM 1997, Marelich 2000)
Weaning protocols are recommended (Mc Intyre Chest 2001, Boles ERJ 2007)
…..but many obstacles (Ely AJRCCM 1999, Vitacca ICM 2001) to implement weaning protocols trainings on a regular basis required, problems with new protocols and new practices acceptance…
Rationale for weaning automation
Control
Patient Monitor Alarms
Ventilator
Control
Patient Monitor Alarms
Ventilator in PSV
PatientPatient
Automated Weaning: SmartCare1) Automated adaptation of PSV level
2) Automated weaning protocol – automatic decrease of the PSV– automatic SBT
Ventilator in PSV
RR, TV, EtCORR, TV, EtCO2Input
Automated pressure support
Automated WeaningOutputAutomaticWeaningSystem
SmartCareProcessing
• Pressure support ventilationPressure support ventilation• Automated adaptation of the PS levelAutomated adaptation of the PS level
Comfort Zone : 15 < RR < 30 breath/minComfort Zone : 15 < RR < 30 breath/min
Tidal Vol > min level, ETidal Vol > min level, ETTCOCO22 < safety limit < safety limit
• Automated weaning strategyAutomated weaning strategy Progressive decrease of the PS levelProgressive decrease of the PS level Spontaneous breathing test before extubationSpontaneous breathing test before extubation Recommendation for extubationRecommendation for extubation
Dojat et al. Int J Clin Monit Comput 1992Dojat et al. Int J Clin Monit Comput 1992
PEEP and FiOPEEP and FiO22 are not managed by the system are not managed by the system
Automated Weaning : SmartCare
0
2
4
6
8
10
12
14
16
18
0:00 0:28 0:57 1:26 1:55 2:24 2:52
Time (h:min)
Level o
f P
ressu
re s
up
po
rt (
cm
H 2
O)
Observation MaintainAdaptation
Minimum level of PS
« Automated SBT »
EXTUBATION
Automated reduction of the
PSV level
Message: « separation from ventilator »
PEEP must be 5 cmH2O
Example of Weaning with «SmartCare »Example of Weaning with «SmartCare »
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Intellivent stems from ASV
• ASV = Pressure controlled and Pressure assisted mode
– Automatic transition from controlled to assisted ventilation
– Automatic adjustement of RR (Ti/Te) and TV (Pressure, cycling off) for
• Constant minute ventilation SET BY THE CLINICIAN WITH ASV
• Minimized work of breathing (based on patient’s respiratory mechanics: time
constant and resistance continuously evaluated)
• Minimized intrinsic PEEP
– Based on physiologic Otis and Meade equations
– With ASV NO ADJUSTMENT OF PEEP AND FiO2
INTELLIVENT
Otis, JAP 1950Mead, JAP 1960
Control
Patient Monitor Alarms
Ventilator
Control
Patient Monitor Alarms
PatientPatient
Automated Ventilation : Intellivent1) Ventilation controller: Automated adaptation of minute ventilation (RR, TV) / EtCO2
2) Oxygenation controller: Automated adaptation of PEEP and FiO2 / SpO2
RR, TV, EtCO2Input
Automated Ventilation (RR,TV)
Automated Oxygenation (PEEP/FiO2)
Output
AutomaticWeaningSystem
IntelliventProcessing
SpO2, Heart Lung Index
PEEP limitation - Heart-Lung Index (HLI)
HEART vs LUNG: not OK HEART vs LUNG: OK
Pulse oxymeterPlethysmogram
(mm)
Arterial Pressure(mmHg)
Airway Pressure(cmH2O)
Delta PP
Delta POP
Adaptive Support Ventilation
Still 3 knobs…
Intellivent: the NO knobs concept…
FULLY AUTOMATIC
Intellivent = fully automaticGender, patient height
estimation of the target minute ventilation
Clinical situations modifies the target for the controllers
Press Start !
Ventilation controller
ASV
Oxygenation controller
EtCO2
SpO2
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Dojat et al. AJRCCM 1996Dojat et al. AJRCCM 1996 Good performances of the system to predict extubation success/failuresGood performances of the system to predict extubation success/failures38 patients38 patients
Dojat et al. AJRCCM 2000Dojat et al. AJRCCM 2000Efficiency of the system to maintain the patient in a comfort zoneEfficiency of the system to maintain the patient in a comfort zoneReduction of time with high PReduction of time with high P0.10.1
56 modifications of PSV/24 hrs vs 1 modification PSV/24 hrs56 modifications of PSV/24 hrs vs 1 modification PSV/24 hrs10 patients10 patients
Dojat et al. AJRCCM 1992Dojat et al. AJRCCM 1992Maintain of the patients in the comfort zone 95% of timeMaintain of the patients in the comfort zone 95% of time19 patients 19 patients
INITIAL CLINICAL EVALUATIONS OF SMARTCARE(prototype = NéoGanesh)
Bouadma, Lellouche et al. Intensive Care Med 2005Bouadma, Lellouche et al. Intensive Care Med 2005Possibility to ventilate patients with the system during prolonged periods (up to Possibility to ventilate patients with the system during prolonged periods (up to 12 days)-Pilot study for multicenter RCT12 days)-Pilot study for multicenter RCT42 patients42 patients
YES
NO
YES NO
YES
EXTUBATI ON
NO
YES
YES
NO
Mechanical ventilationQuestion at least 2 times a day:
Weaning possible ?
Initiation of weaning• Stop or lowering of sedation• Level of Pressure Support : 20 cmH2O
Question at least 2 times a day: Spontaneous breathing test feasible ?
PS level 20 cmH2O above PEEP > 60 minutes ?
NO
Patient weaned but extubation not possible
- Level of consciousness OK- Efficient swallowing- Efficient cough
Extubation possible ?
Spontaneous breathing test during 30'First choice: Pressure support 10 cmH2O, ± PEEP 5 cmH2OOther choices: - T-piece trial- CPAP, flow 30 l/min. PEEP 5 cmH2O
Extubation criteria present ?
Extubation criteria (all must be present)- Respiratory rate 30/'- Pulse < 120/'- Syst. ABP < 180 and > 90 mmHg- No hemodynamic instability- PaO2 8.5 kPa and FIO2 0.40- pH > 7.30
Adaptation of PS and/or
PEEP level
Spontaneous breathing test feasible if after 60' withPS 20 cmH2O, PEEP 5 cmH2O (all must be
present):- Respiratory rate 30/'- Tidal volume 6 ml/kg- No hemodynamic instability- SpO2 90% and FIO2 0.40- No other contra-indication
Weaning possible if all following criteria are present:- Improvement of condition having led to intubation - Absence of uncontrolled severe infection- Correction of metabolic disorders- Adequate hemoglobin level - No hemodynamic instability- PaO2 > 8.5 kPa with FIO2 0.40 and PEEP 5 cmH2O
YES
NO
YES NO
YES
EXTUBATI ON
NO
YES
YES
NO
Mechanical ventilationQuestion at least 2 times a day:
Weaning possible ?
Initiation of weaning• Stop or lowering of sedation• Level of Pressure Support : 20 cmH2O
Question at least 2 times a day: Spontaneous breathing test feasible ?
PS level 20 cmH2O above PEEP > 60 minutes ?
NO
Patient weaned but extubation not possible
- Level of consciousness OK- Efficient swallowing- Efficient cough
Extubation possible ?
Spontaneous breathing test during 30'First choice: Pressure support 10 cmH2O, ± PEEP 5 cmH2OOther choices: - T-piece trial- CPAP, flow 30 l/min. PEEP 5 cmH2O
Extubation criteria present ?
Extubation criteria (all must be present)- Respiratory rate 30/'- Pulse < 120/'- Syst. ABP < 180 and > 90 mmHg- No hemodynamic instability- PaO2 8.5 kPa and FIO2 0.40- pH > 7.30
Adaptation of PS and/or
PEEP level
Spontaneous breathing test feasible if after 60' withPS 20 cmH2O, PEEP 5 cmH2O (all must be
present):- Respiratory rate 30/'- Tidal volume 6 ml/kg- No hemodynamic instability- SpO2 90% and FIO2 0.40- No other contra-indication
Weaning possible if all following criteria are present:- Improvement of condition having led to intubation - Absence of uncontrolled severe infection- Correction of metabolic disorders- Adequate hemoglobin level - No hemodynamic instability- PaO2 > 8.5 kPa with FIO2 0.40 and PEEP 5 cmH2O
Weaning process can begin if:
The cause of the respiratory failure is partially or completely controlled, including a
SpO2 90% under FIO2 0.5 and PEEP 5 cm H2O
Hemodynamic stability (Systolic Blood Pressure between 90 and 160mm Hg + Pulse
between 60 and 125 /minute + absence of uncontrolled arrhythmias)
Temperature < 39°C
Haemoglobin 8 g/dL
Absence of significant hydro-electrolytes abnormalities
Patients can follow simples orders and there is not need for high dose of sedatives
For neurological patients:
Glascow Coma Scale > 8, Intra-Cranial Pressure < 20 mmHg, Cerebral Perfusion
Pressure > 60 mmHg
Those patients who accomplish these criteria will follow a spontaneous breathing test (2 hours
T tube or Pressure Support Ventilation with 7 cm H2O of pressure support and Positive End
Expiratory Pressure 5 cm H2O). No tolerance to spontaneous breathing test will be
considerer if:
Respiratory Rate > 35 bpm + clinical manifestation *
Hypoxemia (PaO2 < 60 mmHg under O2 flow 4 L/min)
Acidosis (pH 7.3)
* Clinical manifestations: Systolic Blood Pressure 160 mmHg or 90 mmHg, Heart Rate
140 bpm or augmentation of 25% of baseline, new arrhythmia, lower conscience level,
sweating or agitation.
1. Patients will be extubated if they successfully complete the 2 hours spontaneous
breathing trial and they have an adequate cough
2. For patients that do not tolerate the spontaneous breathing test, weaning will continue
on Pressure Support Ventilation. Pressure Support will be adjusted to achieve a
respiratory frequency of 25-30 bpm and a good clinical adaptation. Pressure Support
will be diminished as soon as possible following patient’s clinical tolerance. Patients
will be extubated if tolerating low Pressure Support levels (next to 10 cm H2O) with
low PEEP levels ( 5 cm H2O) if clinical tolerance and cough are adequate.
1st Multicenter Randomized Study Objective of the study
Automated weaning Usual protocolized weaningVS
Primary end point:
Weaning time (inclusion first extubation)
Primary end point:
Weaning time (inclusion first extubation)
Lellouche et al, AJRCCM 2006,174:894-900
WEAN pilot studyCo-PI: K.Burns/F.Lellouche
RCTPILOT/ FEASABILITYSmartCare vs written weaning protocols8 CentersPrimary outcomeacceptance of weaning protocols
OUTCOME DATA
Variables Protocol Weaning (n=43)
Automated Weaning
(n=51)
p-value
Time to first extubation, days median (25-75) 4 (2-12) 3 (2-5) 0.02Time to first successful extubation, days median (25-75) 5 (3-19) 4 (2-7) 0.10Reintubation, n (%) 11 (25.5%) 9 (17.7%) 0.35Patients with prolonged ventilation (>21 days), n (%) 6 (18.2%) 0 0.01Ever had tracheostomy, n (%) 15 (34.9%) 8 (16%) 0.04Total duration of intubation, days median (25-75) 10.5 (8, 17.5) 12 (6, 25) 0.37Duration of ICU stay, days median (25-75) 9 (5, 25) 7 (5, 14) 0.13Duration of Hospitalization, days median (25-75) 31.5 (16. 49.5) 22 (14, 33) 0.19ICU death, n (%) 9 (20.9%) 9 (17.7%) 0.69
Feasibility for a larger RCT ?......
Automated weaning (SmartCare) vs local weaning protocols in post-surgical patients
Randomized Controlled TrialPost-op patients with MV > 9 hours300 patients included
94±144 hours (SmartCare)118±165 hours (Protocols)
(P=0.12)
Rose Intensive Care Medicine 2008
Randomized Controlled TrialMedical patients102 patients included
Schadler, ATS 2009Lellouche, AJRCCM 2006
In the context of increasing gap between needs and supply to manage patients on MV, both studies are positive :
Better (or same outcome) with less human interventions
EVALUATION OF INTELLIVENT = FULLY AUTOMATIC MECHANICAL VENTILATION
Feasibility study Does the system can safely manage stable patients after cardiac surgery ? Does the system reduce the workload ?
Context: recent data (from cardiac surgery database) showing the need to reduce tidal volume after cardiac surgery (prophylactic protective ventilation…)
Non parametric logistic regression
Impact of tidal volumes even in patients with normal lungs
3434 patients after CABG or valve surgeryMultivariate analysis High tidal volumes after cardiac surgery are independant risk factors for
- organ dysfunction- ICU Length of stay
Lellouche et al ATS 2010
Cardiac surgery= interesting to evaluate a fully automated system
• Dynamic clinical condition• Within 2-4 hours
– Temperature 35˚C 37˚C (↗CO2 production)
– FiO2 70 40-30%
– Controlled assisted ventilation
• Workload related to mechanical ventilation settings: – Adjustment of minute-ventilation– PEEP/FiO2 weaning
– Switch to PSV
Criteria for Consent SURGERY Inclusion criteria +
Exclusion criteria -
Consent ICU admission
Connection to a G5 ventilator
Settings by the anesthesiologist
15 minutes
Intellivent groupAutomated ventilation
Modified G5
Control group Protocolized Ventilation
G5 : SIMV+PSV
Randomization
4 hours
- Hemodynamic stability 1. < 3 red-cell Tf units within last 15 min 2. Epi or norepinephrine below < 1 mg/h 3. Bleeding <100 ml within last 15 min- No anuria
- Unexpected surgical procedure- Major complication during surgery- Early extubation expected (< 1 hour)- Broncho-pleural fistula- Study ventilator not available
Inclusion Criteria
Exclusion Criteria
Study design
Data from the ventilator recordedTiming of the interventionsTime with optimal/non optimal ventilation
RESULTS
- 90 consent signedDelayed surgery (morning to afternoon cases)Surgery postponed (emergent cases)Hemodynamic instability at ICU arrival
60 patients included from 07/2009 to 12/2009
. ALL THE PATIENTS COMPLETED THE STUDY
. 1 patient needed re-operation for massive bleeding 1 hour after the randomization (Intellivent group).
. Duration of the study (min):Control group Intellivent group P value 194 + 43 207 + 47 0.24
5
6
7
8
9
10
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15T
idal
Vo
lum
e (
ml/
Kg
PB
W)
Conventionnal
Intellivent
H0 H1 H2 H3 H4
* * *
RESULTS: MAIN OUTCOME
% n
Number of manual settings
148
5
Control arm
Intellivent arm
Control arm
Intellivent arm
Optimal ventilation (TV < 10ml/Kg of PBW, Pressure < 30, SpO2, EtCO2)
**
Why automated modes are required ?
SmartCare: automated adjustment of pressure support, automated weaning
Intellivent: automated mechanical ventilation
Clinical evaluationSmartCareIntellivent
Conclusion: even equivalent would be worth…..
PLAN
Computers in ICU: panacea or plague ?East TD, Respiratory Care 1992
Conclusion:
Even results equivalent to traditionnal modes would be worth…..in the demographic context
Several studies demonstrate positive results to reduce the duration of mechanical ventilation and potential for workload reduction
With…first generation systems
More evaluation required (Intellivent …)
Room for improvement in the next years
AUTOMATED MODES OF VENTILATION: SUPERIOR TO TRADITIONNAL MODES ?
AUTOMATED MODES OF VENTILATION: SUPERIOR TO HUMAN SETTINGS ?
We should accept that automated systems could be superior to humans for specific tasks…
THANKS !
PA BouchardC BouchardMC FerlandP Dubé….