1) ECMO and ECCO2R are being re-examined as alternatives to invasive mechanical ventilation for critically ill patients, as the technologies have improved. 2) Specifically, ECMO is being used instead of mechanical ventilation for some patients awaiting lung transplantation, with promising results. 3) While ECMO and ECCO2R may help reduce ventilator-induced lung injury and duration of mechanical ventilation, more research is still needed to determine if they can fully replace invasive mechanical ventilation.

1. Assistant Professor of Critical Care
Cairo University
Will ECCO2R & ECMO
Replace Invasive
Mechanical Ventilation?

2.  Extracorporeal membrane oxygenation
(ECMO) is not a newly developed
technique.
 The main aim of ECMO development was
trying to maintain tissue oxygenation
through bypassing the lungs when other
strategies fail.
History

3. History
The theory was to develop a membrane
lung that can withstand hydrostatic pressure
and is permeable to gas exchange

4. Bramson
ECMO
machine
Use of the Bramson Membrane Lung
J. Donald Hill, MD; Thomas G. O’Brien, MD’ James J. Murray, MD’ Leon Dontigny, MD; MI
Bramson, ACGI, J.J. Osbprm. MD; and F. Gerbode, MD

5. History
The theory although very attractive
and logic has faced many challenges
over years.

6. Challenges
Challenge was the mode of bypass in
respiratory failure which changed from
Veno- Arterial (VA) to Veno-venous
(VV) sparing a lot of potentially life
threatening complications.

7. Challenges
Challenge was the associated coagulopathy:
1. Coagulation system activation through tissue
factor activation.
2. Platelet adhesion and activation resulting in
thrombocytopenia and thrombasthenia.
3. Massive anticoagulation use to prevent
thrombosis of the older huge membrane lungs
with consequent bleeding and need for
massive blood transfusion .

8. Challenges
Was hemolysis created by the roller pump
and early generation centrifugal pumps
which improved with newer centrifugal
magnetically driven pumps.

9. Challenges
Was the thrombogenicity and inflammatory
response which markedly improved after
development of heparin coated and bioline
coated circuits that need less anticoagulation
and less inducer of inflammatory response.

10. Challenges
Was the miniaturizing of ECMO
consoles that allowed ECMO
retrieval.

11. Challenges
Was the lack of strong evidence in
favor of ECMO use over standard therapy.

12. Challenges-Evidence

14. Caveats of this first study:
 “Outdated” devices
 Veno-arterial bypass only
 ECMO weaned systematically at D5
 Prolonged MV before randomization
 “Old-fashioned” MV
 Profound anticoagulation

15. Despite That

19.  ELSO registry from 1986–2006.
 1,473 patients with severe respiratory
failure 50% survived to hospital discharge.
 Median age was 34 years.
 Most patients (78%) supported with
venovenous ECMO.

20.  Time from
randomizati
on to death
 Log rank
p = 0.03

21. Influenza A (H1N1) …

22. ECMO in H1N1
H1N1 epidemic in 2009 resulted in
the spread of ECMO use in
developed countries

23. ECMO in H1N1-ELSO data

24. Extra corporeal
CO2 Removal
(ECCO2R)

25. When hypercapnia is the driving
force behind the need for invasive
mechanical ventilation, ECCO2R could
facilitate discontinuation of positive-
pressure ventilation by rapidly removing
carbon dioxide, thereby reducing minute
ventilation, work of breathing, and
dynamic hyperinflation.

26. This can be achieved by using much
lower flows than nedded on ECMO
with consequently smaller cannulae and
membrane sizes.
ECCO2R

29. Luciano Gattinoni, JAMA 1986;256:881-886
 43 patients, uncontrolled study
 Low-flow veno-venous CO2 removal device
• ECCO2-R
 To avoid lung injury from conventional MV, the
lungs were kept "at rest"
• 3-5 breaths/min
• “Low” peak airway pressure, 35-45 cm H2O
 Survival: 21/43 (48.8%) patients
 Lung function improved in 31(72.8%) patients
 Blood loss: 1800±850mL/day…

30. Morris, AH, AJRCCM,
 Randomized controlled clinical trial
 40 patients with severe ARDS
 Extracorporeal CO2 removal:
• ECCO2R
• Low-flow veno-venous device
 Survival at 30 days not significantly different:
• 42% in the 19 mechanical ventilation
• 33% in the 21 ECCO2R patients (P = 0.8)
• All deaths occurred within 30 days of
randomization
 Study stopped for futility.
 >30% patients with severe hemorrhage.

36. Hemolung, Alung Technologies

42. Invasive mechanical ventilation is associated with
numerous problems:
 Ventilator-associated lung injury,
 Ventilator associated pneumonia, dynamic
hyperinflation, suboptimal delivery of
aerosolized medications,
 Patient discomfort, reduced oral intake and
mobility.
Crit Care med 2008; 36:1614-1419.,Proc Am Thorac Soc
2008; 5:530-535.Am J Respir Crit Care Med 1999;
159:1249-1256. Resp. Care 2002; 47:1279-1288,
discussion 1285-1289.

43. Deconditioning may occur without
aggressive physical therapy, and invasive
mechanical ventilation is associated with high
1- and 5-year mortality rates.

45. ECMO as Bridge to Lung
Transplantation Invasive mechanical
ventilation is considered a relative
contraindication to lung transplantation,
as it often leads to poor post-transplant
outcomes (44, 45).

46. K.M Olson

51. Centers have reported successfully
starting ECMO instead of invasive
mechanical ventilation, bypassing the
ventilator entirely.
The specific patient populations for
whom these strategies are most appropriate
have yet to be defined.

52.  ARDS net strategy might not protect
against tidal hyperinflation
• When Pplat remains >28-30 cm H2O
 Further decrease of Vt
• From 6 to 5, 4 or 3 ml/kg IBW
• To decrease Pplat <25 cm H2O
• To further reduce VILI
• With sufficient PEEP to prevent lung
derecruitment

53.  Reducing Vt causes hypercapnia
 Induced Hypercapnia might cause…
• Pulmonary hypertension
• Decreased myocardial contractility
• Decreased renal blood flow
• Elevated intracranial pressure
• Release of endogenous catecholamine
 Induced Hypercapnia should be controlled by
extracorporeal CO2 removal
• “CO2 dialysis”
• Low-flow devices

54. Ventilation
High VT
12/15 ml/Kg
Extracorporeal
Permissive
Hypercapnia
Lung Protective
Strategy
Low VT
6 ml/Kg?
No ventilator?

56. The use of extracorporeal support
inherently introduces risks that would not
otherwise be present wit conventional
mechanical ventilation alone, including
hemorrhage, thrombosis, and catheter
associated infections.

58.  For acute decompensation of COPD
 In case of failure of NIV
• To prevent intubation and MV
 After intubation
• To permit rapid extubation
 To allow patient ambulation and
rehabilitation of the patient

63.  ECMO and ECCO2R are revisited in critically
ill patients with better technologies and safety
profile.
 Classically VV ECMO is still considered as
salvage treatment in acute respiratory failure
when standard treatment fails.
 ECMO is being used instead of mechanical
ventilation in patients waiting for
transplantation with encouraging results

64.  ECMO and ECCO2R might be helpful in
reducing VILI and decreasing ventilator
days.
 Whether ECMO and ECCO2R can
replace invasive mechanical ventilation
is yet to be studied.