Laurent Brochard Toronto

Laurent Brochard Toronto

Synchronie Patient-Ventilateur

Conflicts of interest

• Our clinical research laboratory has received research grants for clinical research projects from the following companies: – Covidien (PAV+)

– Dräger (SmartCare)

– General Electric (FRC)

– Philips (NIV-sleep)

– Fisher Paykel (High flow)

– To the Hospital: Maquet (NAVA)

Dose of support? D

ysfu

nct

ion

Quantity of Ventilatory Support

Respiratory Distress

VILI VALI VIDD

Normal

Patient-Ventilator Asynchrony

Patient-Ventilator

Asynchrony

ICU ventilators

Servo I

Engström Galileo

Evita 4

Extend

Avea

PB 840

Pes

Paw

Good Synchrony: Paw follows Pes

time

Clinical consequences of asynchronies?

•Dynamic hyperinflation

•Excessive or insufficient ventilatory assistance

•2)

•1)

•3) •Sedation

•4)

•5) •Errors in assessing weaning readiness

•6) •Prolonged duration of ventilation

•Sleep fragmentation

•7) •Respiratory sequelae...

ICM 2006

Multivariable model : mechanical ventilation duration for the group of patients with asynchrony index>10% was 10 days, 95% CI

(4.1; 25.0) compared to 4 days, 95% CI (2.7; 5.6) for the group of patients with ITI <10% (p .0004).

De Wit CCM 2009

Blanch L et al. ICM 2015

Assistance in excess

• Apneas

• Ineffective Efforts or Missed Cycles

Pressure support ventilation

Pressure support ventilation

1 min Parthasarathy. AJRCCM 2002;166:1423

C4-A1

O3-A2

ROC

LOC

Chin

Leg

VT

RC

AB SpO2

EKG

Assist-Control Pressure Support Arousal

2002

Assist-Control, PEEP 10 cmH2O

Triggering asynchrony Chao et al., Chest 1997; 112: 1592-1599

Assist-control, ø PEEP

-2

0

2

4

6

0 2 4 6 8

Wasted Effort: Ineffective breath

Esophageal

Pressure

(cmH2O)

0

5

10

15

20

25

Airway

Pressure

(cmH2O)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8Pressure drop

Flow increase

Time (s)

Flow

(L/s)

Intrinsic

PEEP

Ineffective triggering

Start of patient’s effort

Start of ventilator insufflation

-0,6

-0,4

-0,2

0

0,2

0,4

0,6

0,8

0 2 4 6 8 10 12

-10

-5

0

5

0 2 4 6 8 10 12

0

5

10

15

20

25

0 2 4 6 8 10 12

Weak effort

Flow

(L/min)

Airway

Pressure

(cmH2O)

Esophageal

Pressure

(cmH2O)

-1

-0.5

0

0.5

1

0 3 6 9 12

0

10

20

30

40

0 3 6 9 12

Time (s)

-1

-0,5

0

0,5

1

1,5

0 3 6 9 12 15

0

10

20

30

0 3 6 9 12 15

Airway

Pressure

Flow

PSV

ACV

Flow

Airway

Pressure

Delayed

triggering Delayed cycling

Ineffective Triggering

Patient Respiratory Rate (min-1)

0

5

10

15

20

25

0 1 2 3

0

5

10

15

20

25

0 1 2

0

5

10

15

20

25

0 1 2 3

0

5

10

15

20

25

0 1 2

Airway Pressure (cmH2O)

Baseline PS-ZEEP

Baseline PS-PEEP

Optimal PS Optimal Ti

Time (s)

Intensive Care Med 2008

Thille et al., Intensive Care Med 2008

0

10

20

30

40

50

60

PS basal PS optimal

Asynchrony Index (%)

Baseline PS-PEEP

Optimal PS

Thille et al., Intensive Care Med 2008

Baseline PS Optimal PS

PS (cmH2O) 20.0 [19.5-20.0] 13.0 [12.0-14.0]

RR ventilator 16.1 [12.4-17.2] 22.4 [22.0-31.3] *

RR patient 26.5 [23.1-31.9] 29.4 [24.6-34.5]

Ti Ventilator (s) 1.3 [1.0-1.8] 0.8 [0.8-1.0] *

PTP (cmH2O.s/min) 61 [58-81] 82 [61-106]

VT (ml) 571 [487-638] 349 [336-368] *

VT (ml/kg, IBW) 10.2 [7.2-11.5] 5.9 [4.9-6.7] *

Reducing tidal volume to reduce patient-ventilator asynchrony

Thille et al., Intensive Care Med 2008

(Hidden) Assistance in excess

• Auto triggering

Short cycle and distortion of flow signal

No airway pressure drop at the beginning of the cycle

No effort

When to suspect

auto-triggering ?

During controlled ventilation:

• RR > adjusted RR

• Respiratory alkalosis

During assisted ventilation:

• Sudden increase or persistently

high respiratory rate

•Absence of an airway pressure

drop at beginning of the cycle

• PSV: short cycle with a flow

signal distortion

• ACV: abrupt airway pressure

increase

Imanaka H, et al. Crit Care Med 2000; 28:402-407

Insufficient Assistance

• Double triggering, breath stacking and short cycles

-5

0

5

10

0 2 4 6 8 10

-5

0

5

10

0 1 2 3

0

5

10

15

20

0 1 2 3

-0,8

-0,4

0

0,4

0,8

1,2

0 1 2 3

-0.8

-0.4

0

0.4

0.8

1.2

0 2 4 6 8 10

0

5

10

15

20

25

30

0 2 4 6 8 10

Flow

(L/min)

Airway

Pressure

(cmH2O)

Esophageal

Pressure

(cmH2O)

Beginning of patient’s effort

End of patient’s effort

Double Triggering

Continuation of

patient’s effort

A B

Under Assistance

ACV

KALLET et al., Critical Care Med 2006; 34:8-14

Excessive Sedation?

• Respiratory Entrainement or Reverse Triggering

A

EAdi (µV)

Paw (cm H2O)

Flow (L/sec)

Respiratory Entrainment

Akoumianaki E et al Chest 2012

Paw (cm H2O)

Flow (L/sec)

EAdi (µV)

Accidental observation…

Flow

Paw

Pes

VT

Clinical consequences: VT increase

Clinical consequences: double cycle

Tool: screen and ventilator waveforms

Education and Training

Automated Monitoring

Excessive Assistance : apneas, ineffective efforts

Insufficient Assistance : Short Insufflation & double cycles

Reverse triggering

Autotriggering

Patient Ventilator dys or a-synchrony