8. •ECMO-extracorporeal circuit to provide
temporary respiratory or cardiac support to
patients failing conventional therapy
TECHNOLOGY OF CARDIOPULMONARY
BYPASS TO BEDSIDE
Extracorporeal Membrane Oxygenation
(ECMO)
9. How ECMO works
• External artificial circuit carries venous blood from the patient
to a gas exchange device (oxygenator) where blood becomes
enriched with oxygen and has carbon dioxide removed.
• The blood is then returned to systemic circulation
via another vein (VV ECMO) or artery (VA ECMO).
12. Veno Arterial ECMO Indications
1. Cardiogenic shock: AMI and complications (wall ruptu
re, papillary muscle rupture, refractory VT / VF)
2. Post cardiac surgery: unable to wean safely from cpb
3. Sepsis with profound cardiac depression
4. Drug overdose with profound cardiac depression
5. Myocarditis
6. Chronic cardiomyopathy: as a “bridge” to longer term
ventricular assist device or transplant
13. Ecmo principle
• Patient care during ECMO has focused on the end organ
perfusion and thus preventing further injury and also
improving or maintaining end organ functions
• Bridge to Decision and to Recovery
14. HISTORY
• First successful implantation of ECMO dates
from 1972
• 1975 – RH Bartlett - First Successful Neonatal ECMO
20. ECMO technical advances
A move from roller to centrifugal pumps that do
not damage the red cells
Roller Pump Head
Centrifugal Pump He
ad
Centrifugal Pump Co
nsole
Roller Pump C
onsole
Centrifugal Pum
p Drive Unit
21. ECMO technical advances
A switch from silicone membrane oxygenators to
polymethylpentene hollow fibre ones
Silicone membrane ox
ygenator unravelled
25. 26
Downside
Complications
BLEEDING, COAGULOPATHY AND HAEMOLYSIS
MECHANICAL COMPLICATIONS (e.g. oxygenator failure, circuit disruption,
pump malfunction, problems with cannula placement/removal)
HIT, INFECTION
AIR EMBOLISM, THROMBOEMBOLISM AND NEUROLOGICAL SEQUELAE
COMPARTMENT SYNDROME AND LEG ISCHEMIA
26.
27. Contraindications
• Irreversible neurological injury
• Malignancy with limited survival
• Multiple trauma/hemorrhage
• Multi organ failure
• Coagulopathy
• Severe aortic valve regurgitation
• Aortic dissection
28. How do we do it ?
• Ecmo team discussion
• Family counselling
• Cannulation and anticoagulation
• Ecmo circuit establishment and maintainance
• Ventilation and ICU measures
• Daily team discussion and prognostication
• Weaning
29. THE ECMO TEAM
• CTVS team
• Perfusionist
• Primary care physician
• Intensive care team
• Pulmonologist
• Nursing team
• Respiratory therapist
• Physiotherapist
30. When to start?
• Severe, life threatening hypoxemia –P/F less than 100
• Lack of recruitment response
inadequate SpO2/PaO2 response to increasing PEEP
• Failure of prone ventilation
• Murray score of more than 2.5 to 3
• Oxygenation index >40 x 2 hours-indicates ecmo
• Ventilator days pre-ECMO
• Compliance < 0.5 ml/cmH2O/kg
35. “The key to the success of ECMO may be the time
of initiation”
Basic goals:
»
» Decrease further lung damage
»
» Reduce oxygen toxicity
» “Lung Rest”
» Maintain end organ perfusion
»
36. REST THE LUNG
• Tolerate pCO2 55-65, SpO2 > 88%, Sao2 > 90%
REST LUNG SETTINGS
Limit Plateau pressures <30 cm H2O
Delivered tidal volumes 4 ml/kg
Rate 8-10 breaths/minute
PEEP 12-14 cm H2O
Inspiratory time longer
Goal FiO2 0.4-0.6
40. Weaning
• Turning off the gas flow to the oxygenator and
simultaneous reestablishing full ventilation is required- VV ECMO
• Circuit flows must be reduced to assess native heart function
(≤ 1.5 LPM) –VA ECMO
• Lower limb arterial /venous Doppler studies
-following decannulation as to prevent distal limb
ischaemia and distal DVT formation