VA- and VV-ECMO

A tutorial…

Alain Combes

Service de Réanimation

iCAN, Institute of Cardiometabolism and Nutrition

Hôpital Pitié-Salpêtrière, AP-HP, Paris

Université Pierre et Marie Curie, Paris 6www.reamedpitie.com

Conflict of interest

Principal Investigator: HEROICS trial HVHF after complicated heart surgery NCT01077349 Sponsored by GAMBRO

Principal Investigator: EOLIA trial VV ECMO in ARDS NCT01470703 Sponsored MAQUET, Getinge Group

Received honoraria from MAQUET, Getinge Group

The ECMO

extracorporeal circuit

Centrifugal pump

Membrane oxygenator

Controller

Cannulas

Tubing

The ECMO circuit:

Centrifugal pump

Electrical

Centrifugal pump

0->4000 RPM

Can deliver flows up to 8 L/min

Very reliable

Up to 21 days

The ECMO circuit:

Membrane Oxygenator

Hollow fiber membrane oxygenator

Polymethylpentene

Heparin-coated

High performance

CO2 elimination

Blood oxygenation

Low pressure drop

Long duration 15-21 d

The ECMO circuit:

Central Unit Controller

Flow alarms

The ECMO circuit:

Cannulas

Percutaneous insertion of the Cannulas (Seldinger) Drainage Cannula:

• Femoral Vein

• Long cannula: up to 60 cm

Return Cannula:

• Oxygenated blood

• Femoral artery

• Shorter cannula: 20-25 cm

Cannulas Diameter+++ 22 – 30 Fr for drainage 15 – 23 Fr for return

Poiseuille’s Law…

Flow function of the 4th power of cannula diameter

Maximize drainage cannula diameter

25-30 Fr

To decrease pump speed, pressure and blood trauma

VA-ECMO for refractory

cardiogenic shock…

ECMO is now the

first line device…

In the context of acute refractory cardiac failure

Extracorporeal Membrane

Oxygenation: ECMO/ECLS

ECMO = ExtraCorporeal Membrane Oxygenation:

Centrifugal Pump + Oxygenator: Heart-Lung support

Peripheral vascular access:

Femoral site (cannulas), Seldinger technique, limited cut-down

Advantages

Easy and rapid implantation if peripheral ECMO

• No sterno/cardiotomy, local anesthesia, Emergency situations

Provides high and stable output flow

Simultaneous cardiac and pulmonary assistance: ECMO

Bridge to: Recovery, Bridge, Transplantation, Withdrawal

“Low cost” (2 - 40 times cheaper / other devices)

ECMO program at La Pitié, Paris

020406080

100120140160180200220240260280

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Total

Post CPB

Medical

Portable ECMO

Program

ECMO: Cannulas

Therapeutic Strategy:

When to initiate mechanical assistance?

Parameters to evaluate: Etiology/Time course of the disease Treatments administered Clinical status, in particular neurological status:

• Is it futile to insert a device?

Other clinical signs associated with rapid deterioration of cardiac function: Nausea, abdominal pain, Alteration of

consciousness Tachycardia, rhythm disturbances Ionic disturbances, Acidosis Hepatic / Renal failure

Doppler-Echocardiography +++ LVEF <20% Signs of low cardiac output, Ao VTI <8cm

Independent predictors of ICU death

The classical indications of

mechanical assistance…

4 types of indications:

« Bridge to recovery »

« Bridge to bridge »

« Bridge to transplantation »

« Destination therapy »

But now… In the acute setting…

Bridge to whatever seems reasonable

Including “withdrawal” after a few days• If refractory MOF…

ECMO vs. BiVAD?

P = ns

Creatinine mol/dlT bilirubin mol/dl

Results of ECMO…

In the context of acute refractory cardiac failure

1993-2002 2002-2009

Long term survival: 68%, 4 (10%) patients had heart transplantation

Independent predictors of ICU death determined at admission:

SAPS II >56 (OR, 10.23) and troponin Ic >12 g/L (OR, 7.49)

ECMO after cardiac

arrest

3-year prospective observational study

ECMO for 59 patients

Aged 18–75 years

With witnessed in-hospital cardiac arrest of cardiac origin

Undergoing CPR of more than 10 min

Compared with patients

Receiving conventional CPR

Matching process based

On a propensity-score

ECMO

60 min

This poor outcome suggests that the use of ECLS should be more restricted following OH refractory cardiac arrest

The Mobile ECMO

rescue team at La Pitié

The Mobile ECMO rescue team at La Pitié:

2005-2009 experience for refractory cardiac failure…

The mobile ECMO rescue team

Centres Patients N (%)

Median distance (range), Km

Median time (range), min

Paris urban agglomeration (7 centres) 25 (29) 4 (4-18) 4 (4-26) Paris region (26 centres) 54 (62) 13 (4-53) 19 (7-46) Outside Paris region (4 centres) 8 (9) 88 (87-243) 60 (64-134) Total (37 centres) 87 17 (4-243) 20 (4-134)

The mobile ECMO rescue team

87 patients 2005-2009

57 males, 28 females

Mean age: 46.1 [13-76]

Etiologies

AMI 46%

Chronic DCM 16%

Other Acute HF= 38%

• Myocarditis 14

• Intoxication 5

• Rythmic 4

• Post-Partum 3

• Hypoxemia 2

• Takotsubo 3

• Anaphylactic 1

• Septic 1

One year survival = 35%

Comparison with in-house patients

In the multivariate analysis

Adjusted for the inotrope score

Stratified for diagnosis and CPR at ECMO start

Mortality at hospital discharge in the

Cardiac-RESCUE Program group was

not statistically different between groups

OR 1.48, 95% CI 0.72–3.00, p=0.29

ICU management of

VA-ECMO

ECMO limitations

Time limitation: 15 – 21 days for femoral ECMO

>2 months using central ECMO

Patient must remain supine

If femoral ECMO

Local Complications :

Hemorrhage, embolism, acute leg ischemia, infection

Stroke: ischemic, hemorrhagic

Pump highly pre- and afterload dependent

Non-pulsatile flow?

Pulmonary edema

Management of pulmonary

edema under peripheral ECMO

ECMO increases LV afterload+++ Solutions to decrease LVEDP

Dobutamine for improving LV ejection Decrease ECMO flow? Intra aortic balloon pump Atrial Septostomy Transeptal LA drainage Impella® 5.0 Switch from femoral to central ECMO

• With a LA, PA or LV drainage cannula…• Use 2 ECMO systems, as for a BiVAD

Driving Lines Surveillance

Frequent surveillance

No folding

No tension• May precipitate pump failure

Maintain lines along leg axis • For >40 cm

• To prevent vessel tear

Special attention when moving the patient…

Patient’s Surveillance

Watch for Leg Ischemia…

Especially if no reperfusion line inserted

Lines “kicking” hard…

Check for hypovolemia

TTE/TEE

CVP

Frequent in case of vasoplegia due to Multiple Organ Failure

Fluid challenge if patent hypovolemia

Check tip of drainage cannula

Should be placed in the RA

Fibrin deposition

The “Harlequin” syndrome…

Flow competition in the aorta

Recovering Heart vs. ECMO pump

If pulmonary function is impaired

“Blue head”: deoxygenated blood directed to the upper part of the body

“Red legs”: oxygenated blood in the lower part of the body

SpO2 probe, blood gases on Right hand/right ear lobe/Right radial artery

Switch to VV ECMO if persistent lung failure

Biological Surveillance

Anticoagulation

Heparin

aPTT: 45-60 sec, 1.5 x control

Aspirin

Stop if Platelets < 50 G/L

Initiate if Platelets > 75-100 G/L

Aspirin + Clopidogrel

When Platelets > 400 G/L

When early/massive fibrin deposition

Anticoagulation problems…

Massive bleeding… In case of MOF

• Massive hepatic failure• Consumption

Stop aspirin, clopidogrel Possible to stop heparin for a few hours… or days…

• The whole circuit is heparin-coated…

Transfusion thresholds • 7-8 g/dl for RBC• <20 G/L for platelets

Clotting Membrane/Cannulas Check for clotting if

• Decrased blood flow, PaO2, Hemolysis• LA/PA/LV drainage

Hemolysis

May occur due to Membrane failure

• Fibrin, Clot formation

Pump with highly turbulent flow Clotting in the cannulas High energy blood suction

• Hypovolemia• Pulmonary artery/Left atrium drainage cannula

• Recovery of native heart function

Bloody diuresis Check regularly serum free hemoglobin

Echocardiography

Flow : Aortic TVI TDI : Ea / Sa

Diastolic filling (E)

Systolic : Parameter (LVEF)

Parasternal short

axis

Echo is fundamental

At the time of cannula insertion

To verify correct positioning of the venous cannula

For daily surveillance

Heart recovery

• Evaluation of weaning success

Complications

• Pericardial effusion

• Tamponnade

• Intracardiac clotting

Weaning from

ECMO…

Echocardiographic criteria

Parameters at minimal ECMO flow

0

40

60

80

100

120

E,

cm

/s

Weaned Not Weaned

0

40

60

80

100

120

E,

cm

/s

Weaned Not Weaned

33 hemodynamically stable patients who tolerated an ECMO

weaning trial the day before successful/unsuccessful weaning

Parameters at minimal ECMO flow

0

10

20

30

40

50

60

70

80

Puls

e p

ressure

, m

mH

g

0

10

20

30

40

50

60

70

Eje

ction fra

ction,

%0

40

60

80

100

120

E,

cm

/s

Weaned Not Weaned

0

40

60

80

100

120

E,

cm

/s

Weaned Not Weaned

33 hemodynamically stable patients who tolerated an ECMO

weaning trial the day before successful/unsuccessful weaning

Parameters at minimal ECMO flow

0

5

10

15

20

25

E/E

a

Weaned Not Weaned

0

40

60

80

100

120

E,

cm

/s

Weaned Not Weaned

33 hemodynamically stable patients who tolerated an ECMO

weaning trial the day before successful/unsuccessful weaning

“Heavy” and/or

Expensive Devices

Not for the acute phase…

VV-ECMO for refractory

respiratory failure…

ELSO registry from 1986–2006

1,473 patients with severe respiratoryfailure

50% survived to hospital discharge

Median age was 34 years

Most patients (78%) supported withvenovenous ECMO

Multivariate logistic regression model

Pre-ECMO factors associated with increasedodds of death were

Increasing age

Decreased weight

Days on mechanical ventilation beforeECMO

Arterial blood pH < 7.18

Hispanic and Asian race vs. white race

VA ECMO vs. VV ECMO

The CESAR trial

Time from randomization to death

Log rank p = 0.03

Influenza A

(H1N1)v09 …

17 (25%)

Et al…

Et al…

Trauma patients

In lung tranplant

patients…

In the case of massive

pulmonary emboli

Can we rely on

guidelines???…

When to decide on the initiation of ECMO?

SDRA lié à la grippe H1N1

Recommandations pour la ventilation

A. Mercat, J-C.M. Richard, A. Combes, J. Chastre, J.D. Ricard, D. Dreyfuss, L. Brochard

Réseau de Recherche en Ventilation Artificielle

(REVA)

ECMO : potential indications

• Refractory hypoxemia: PaO2/FiO2 < 50, persistent *

Despite: FiO2 > 80 %, PEEP (≤ 20 cmH2O)

Targeting Pplat = 32 cmH2O, prone position +/- NOi

• Plateau Pressure ≥ 35 cmH2O

despite reducing PEEP to 5 cmH2O

AND Vt to 4 ml/kg with pH remaining ≥ 7,15

* : Should also account for disease’s type and evolution

Where to perform ECMO?

• Experienced centers:

• With Heart surgeons, intensivists, perfusionists, nurses….

• All experienced in the management of ECMO devices

• ECMO programs should include a

mobile ECMO retrieval team

• Available 24H/7D

• Nationwide or regional EMCO networks necessary

Management of

Venovenous ECMO

ECMO Circuit

configuration for acute

respiratory failure

Venoarterial vs. Venovenous?

Comparison of VV and VA

configurations

VV configuration

Only lung support

Minor cardiac effects

Closed loop

RV/LV pre and afterload mostly unaffected

RV afterload may decrease

Improved oxygenation

VA configuration

Heart and Lung support

Decreases RV preload and pulmonary blood flow

Increases LV afterload

May cause LV stunning

Decreases arterial pulse pressure

ECMO configuration for

acute respiratory failure

Should always be venovenous…

…Except in the case of severe

associated cardiogenic shock

Peripheral VA ECMO is not

indicated for ARF because…

Flow competition in the aorta

Heart vs. ECMO pump

If pulmonary function is impaired

The “Harlequin” syndrome

• “Blue head”: deoxygenated blood directed to the upper part of the body

• “Red legs”: hyperoxygenated blood in the lower part of the body

Not possible to rest the lungs

Vt, Pplat and FiO2 cannot be reduced

Peripheral VA ECMO is not

indicated for ARF because…

VA ECMO increases LV afterload

Risk of myocardial damage/stunning

Complications associated with the arterial line in VA femoro-femoral ECMO

Leg ischemia

Arterial embolism

Massive arterial hemorrhage

ELSO registry from 1986–2006

1,473 patients with severe ARF

50% survived to hospital discharge

Most patients (78%) supported with venovenous ECMO

2009

68 H1N1 patients who received ECMO

77% survived

Most patients (93%) supported with venovenous ECMO

Determinants of arterial blood

oxygenation and

decarboxylation on VV ECMO

Most important determinants of

arterial oygenation during VV ECMO

ECMO Blood flow

Should match cardiac output

Oxygen demand

SvO2

Hemoglobin concentration

Recirculation

Cannula position/cannula type

Pulmonary shunt volume

How to optimize blood oxygenation?

Minimize recirculation Cannulas adequately (re)positionned Fluid loading to correct hypovolemia Adjust pump flow

ECMO flow objective: Pump flow: the major determinant of oxygenation

• >5 - 6 l/min or >3 L/m² or >60% of CO

USE LARGE DRAINAGE CANNULAS!!!

Other parameters Red cells transfusion:

• Increased transfusion threshold to Hb >10 g/dl• Only if persistent low SaO2

VV ECMO Circuit

configuration for acute

respiratory failure

ECMO cannulas

Jugulo-femoral… Femoro-jugular?

One… Two… Three…???

Poiseuille’s Law…

Flow function of the 4th power of cannula diameter

Maximize inflow cannula diameter

25-30 Fr

To decrease pump speed and blood trauma

Flow required to maintain equivalent SvO2

Significantly less flow was required

during Femoro-Atrial VV ECMO

Femoro-Jugular configuration

27 Fr drainage cannula

19 Fr return cannula

Avalon Cannula:

Solution to recirculation???

Mechanical Ventilation of

the patient on

VV ECMO

Allow the lungs to REST!!!

Mechanical Ventilation of the

patient under VV ECMO

Main objective: Minimize VILI Plateau Pressure 20-24 cm H2O Vt set at 1-4 ml/kg of ideal body weight

• If assist controlled mode used

BiPAP or APRV mode possible

Other MV settings PEEP increased to recruit the lungs

• 10-15 cm H2O

FiO2 < 50% Resp Rate 30-35

Patient often deeply sedated and paralyzed at the initial phase

Cohorte REVA Grippe ECMO

Biological Surveillance

Same as for VA ECMO…

Weaning from VV ECMO

VV ECMO Weaning Protocol

Weaning test: Sweep gas flow set at 0 L/min

• FiO2 set at 0.21 on the membrane • Pump flow not modified

Adjust FiO2 and Vt on the respirator

The device may be withdrawn if PaO2 >60 mmHg, SaO2 >90% FiO2 on the respirator <60% Inspiratory plateau pressure <30 cm H2O and if echocardiography reveals no signs of

acute cor pulmonale For at least 1-2 hours and up to 12 hours

Should ECMO be used

for all severe ARDS

patients?

Are there still skeptics????

Hubmayr, Rolf D., M.D.rhubmayr@mayo.edu

At this time, we do not

support the position that as

a nation we should invest in

the development of

additional ECMO centers

Designing

a new trial…

EOLIA:

ECMO to rescue Lung Injury in severe ARDS

EOLIA: ECMO to rescue Lung Injury

in severe ARDS

Multicenter international randomized controlled trial

Best care possible in the ECMO arm

ECMO initiated asap for every patient randomized• Using the most recent ECMO technology

• CardioHelp, from Maquet

Inclusion of some non-ECMO centers with a mobile ECMO rescue team available from the referral center in less than 1 hour

• Transport of randomized patients to the referral center UNDER ECMO

• ECMO managed only in highly experienced centers

“Highly protective” MV• Plateau pressure limited to ≤ 20 cm H2O

EOLIA: ECMO to rescue Lung Injury

in severe ARDS

Best care possible in the control arm

MV protocolized using the “high PEEP – high recruitment” strategy of the EXPRESS trial

To limit plateau pressure <28-30 cm H2O

• Vt limited to 6 ml/kg IBW

“Ethical” cross-over option to ECMO if the patient develops refractory hypoxemia

EOLIA: ECMO to rescue Lung

Injury in severe ARDS

EOLIA: ECMO to rescue Lung

Injury in severe ARDS

Conclusion

Early and rapid recognition of refractory cardiogenic shock

VA-ECMO can save the life of up to 70% of the patients

Poor outcomes if MOF at the time of ECMO institution

For the most severe forms of ARDS, VV-ECMO:

Replaces pulmonary function, Allows ultraprotective MV

Should allow facilitated lung healing

Only experienced centers should run these programs

With a mobile ECMO retrieval team available 24H/7D

Still a controversy on the use of VV-ECMO

Need for a confirmation trial…

La Pitié: 1612 to 2012…