(Extracorporeal Membrane Oxygenation )

Extracorporeal Membrane Oxygenation Part-1Dr.Tinku JosephDM ResidentDepartment of Pulmonary medicineAIMS, KochiEmail: tinkujoseph2010@gmail.com

Contents in ECMO part 1What is ECMO ?Evolution of ECMOTypesIndicationsVeno-venous V/S veno-Arterial ECMO.Cannulation and Circuit

Contents in ECMO part 2Monitoring ECMO patientsVentilatory strategiesSedation and pain controlAnticoagulationComplicationsWeaningVarious ECMO trials. ELSO guidelines. Recent advances

IntroductionMechanical circulatory support has evolved markedly over recent years.

ECMO (extra corporeal membrane oxygenation) has become more reliable with improving equipment, and increased experience, which is reflected in improving results.

ECMO is instituted for the management of life threatening pulmonary or cardiac failure (or both), when no other form of treatment has been or is likely to be successful.

ECMO is essentially a modification of the cardiopulmonary bypass circuit which is used routinely in cardiac surgery.

Introduction

Instituted in an emergency or urgent situation after failure of other treatment modalities.

It is used as temporary support, usually awaiting recovery of organs.

Introduction

Dynamics of ECMOBlood is removed from the venous system either peripherally via cannulation of a femoral vein or centrally via cannulation of the right atrium, OxygenateExtract carbon dioxide

Blood is then returned back to the body either peripherally via a femoral artery or centrally via the ascending aorta.

Extra corporeal Life Support is achieved by :- Draining venous blood- Removing CO2 - Adding oxygen - Returning to circulation - Through either a vein or arteryIntroduction

The physiologic goal is to improve tissue oxygen delivery , remove CO2 and allow normal aerobic metabolism whilst the lung rests

ECMO circulation: - Dual circulation - Nonpulsatile flow

Evolution of ECMO1953-: Gibbon used 1st artificial oxygenation and perfusion support for the first successful open heart operation.Direct exposure of anticoagulated blood to oxygen was successful.Direct gas interface oxygenators -: Dennis, Morrow, Cross, Dewall and Rygg.Kolobow T-: First attempt at ECMO

BARTLETT Father of ECMO1975-: Successfully applied bed side ECLS device to treat newborn with meconium aspiration.Developed of better membrane oxygenators.

Evolution of ECMO

First successful ECMO patient, 1971

J Donald Hill MD and Maury Bramson BME, Santa Barbara, Ca, 1971. (Courtesy of Robert Bartlett, MD)

First Neonatal ECMO survivor..

ESPERANZA-1975The Hope

ESPERANZA-at 21 yearsFirst Neonatal ECMO survivor..

FROM THIS TO THIS

1989-: Over 100 ECMO centers across the world established Extracorporeal Life Support Organization (ELSO).Platform of communication and research.Evolution of ECMO

Summary of History of ECMO

ECMO Society of India 2010 in Mumbai

Modes of ECMO

Modes of ECMO

ECMO can be categorized according to the circuit used

Veno-arterial - VA ECMO provides both gas exchange and circulatory support (Heart & Lung failure)

Veno-venous VAECMO allows gas exchange only (Isolated Lung failure)

INDICATIONS FOR ECMO

Indications for ECMO-VA

Indications for ECMO-VV

Proposed indications of ECMO in ARDS patients

Indications of ECMO for Respiratory failure- AdultsARDSPneumoniaTraumaPrimary graft failure post lung transplantStatus asthmaticusChemical pneumonitisInhalational pneumonitisNear drowning

Post traumatic lung contusionBronchiolitis obliteransAutoimmune lung disease-: Vasculitis, Goodpasture syndrome.Airleak syndromeIndications of ECMO for Respiratory failure- Adults

ARDSPneumoniaStatus asthmaticsChemical pneumonitisInhalational pneumonitisNear drowningBronchiolitisPersistent air leak sydromeRSV infection post CHD surgery.

Indications of ECMO for Respiratory failure- In Pediatric

Inclusion criteriaPresence of any two of the criteria from the following observed over a period of 4 to 6 hours after maximum medical resuscitation.PaO2/FiO2 40%Murrays Score of >3aA gradient >600Hypercapnia with PH of 15 daysIC bleedActive bleeding from noncompressive siteIrreversible neurological statusUnwitnessed arrest or arrest >30minutesGross multi organ failure

Exclusion criteria

Absolute Contraindications to all forms of ECMOAge: > 70 years Active malignancy Severe brain injury Previous Bone marrow transplant, previous transplant (>30 days). AIDSEnd stage chronic organ failure (hepatic, renal)

End stage cardiomyopathy (except for bridge to VAD/transplant)Chronic lung disease (except for bridge to transplant)Multi organ failureSevere mitral or aortic valvular insufficiency or aortic dissection (VA only)Weight >140kgUnwitnessed cardiac arrest or CPR >60minutes

Absolute Contraindications to all forms of ECMO

Relative Contraindications to all forms of ECMOTrauma with multiple bleeding sitesMultiple organ failure

VV ECMO-: Absolute contraindicationsAnticoagulation issuesSevere PAHSevere Rt or Lt heart failureCardiac arrest

VV ECMO-: Relative contraindicationsHigh pressure ventilation (peak insp pressure >30 cm of H2O) for >7days.High FiO2 requirement (>0.8) for >7daysLimited vascular access.Refusal to accept blood products

Aortic dissectionSevere aortic valve regugitationAnticoagulation issuesVA ECMO-: Absolute contraindications

Blood being drained from the venous system and returned to the arterial system.Provides both cardiac and respiratory support.Achieved by either peripheral or central cannulation.

VA ECMO

VA ECMO

Decreases cardiac workReduces cardiac oxygen consumptionProvides adequate systemic organ perfusion with oxygenated blood.Prevents over distension of ventricles. Helps in cardiac recovery.Indications: Already discussed.VA ECMO

VA ECMO

VA ECMO

Advantages and DisadvantagesAdvantagesDisadvantagesBoth cardiac and pulmonary support.Instant haemodynamic supportCannulation of major artery and sacrifice of one carotid in newbornNo mixing of arterial/venous blood.Poor coronary and pulmonary perfusionGood oxygenation at low ECMO flowsSystemic thromboembolismNo recirculation. Nonpulsatile flowOxygenated blood returns to patients arterial circulationIncreased incidence of neurological events

Provides oxygenation Blood being drained from venous system and returned to venous system.Only provides respiratory support Achieved by peripheral cannulation, usually of both femoral veins.VV ECMO

VV ECMO

Drainage from SVC, IVC, Femoral vein.Flow is determined by the size and placement of the drainage catheterCentrifugal pumpMembrane oxygenatorOxygenated blood returned to the right heart.

VV ECMO

AdvantagesPulmonary circulation/oxygenation is maintained.No carotid ligation. Pulsatile waveform maintained.Efficient CO2 removal.DisadvantagesNo control of BP.Inefficiency (recirculation). Hypoxemia (low PO2).

VV ECMO

CannulationThe establishment and maintenance of adequate vascular access is essential for ECMO

Patient age and sizeUnderlying disease & conditionCause of the cardiorespiratory compromiseType of support: Veno-venous (VV) ECMO Veno-arterial (VA) ECMOTime of the event in relation to the peri-operative periodLocationCannulation

For each modality, there are different kinds and sizes of cannulae that can be used

Target ACT should be accomplished before ECMO (heparin 100 units/kg) 3 minutes before cannulation.

Cannulation

Cannulation-VVVenous cannula should be with the largest lumen and shortest length possible.Venous cannula should have side holes.Resist kinkingSmallest double lumen cannula is size 12 Fr ( for V V ecmo in neonate)

Options For Cannulation in VV ECMOTwo CannulasOne double-lumen cannulaD Brodie, M Bacchetta; N Engl J Med 2011; 365:1905-14.

Drainage cannulaAs central as possibleNot too close to the return cannulaReturn cannulaClose to the tricuspid valveBut not too close to the drainage cannula

Cannula Placement

Fem Fem CannulationIndicationCannulation in jugular vein not possible.Higher risk for femoral vein/caval thrombosis(?)

Cannula Choice

Pedersen et al., Ann Thorac Surg 1997

Hemolysis & Cannula Diameter

Q =DP p r48 h L

Flow is proportional to the power of 4 of radiusinversely proportional to tubing length and viscosity1797-1869 Poiseuilles Law

Double Lumen Cannula

Less Recirculation.Single access.Possible ambulation.Bigger cannula and smaller lumen.Image guidance is mandatory.Double Lumen CannulaAvantages:Drawbacks:

CannulationTwo CannulasDouble-lumen

Mobilization: ECMO DevicesMobilization is possible .It probably reduces critical illness polyneuropathy, delirium and muscle atrophy.It may reduce time on ventilation and improve outcome post lung transplantation.

Insertion

Percutaneous insertionGuide-wire Dilators Cannulas: Use the right tools

188 cannulation attempts.11 cannulation failures.3 arterial punctures.One leading to distal necrosis.1 SVC laceration . 1 fatal hemothorax. SVC perforation by Reinfusion Cannula.Venovenous Extracoporeal Life Support Via Percutaneous Cannulation in 94 Patients*Thomas Pranikoff, MD; Ronald B. Hirschl, MD; Robert Remenapp, RRT; Fresca Swaniker, MD and Robert H. Bartlett, MD, FCCPChest 1999; 115:818-822.

Transesophageal Echocardiographic Guided Placement of a Right Internal Jugular Dual-Lumen Venovenous Extracorporeal Membrane Oxygenation (ECMO) CatheterMazzeffi M J Cardiothorac Vasc Anesth, 2013

Mid-esophageal four-chamber TEE view with white arrow showing improperly positioned cannula in the right ventricle.Modified mid-esophageal bicaval TEE view using color Doppler compare mode showing return blood flow in the center of the right atrium directed towards the tricuspid valve. (Color version of figure is available online).

Dolch et al, ASAIO, 2011.

Always use ultrasound guidance

Ultrasonic locating devices for central

venous cannulation: meta-analysisDaniel Hind, Neill Calvert, Richard McWilliams, Andrew Davidson, Suzy Paisley, Catherine Beverley, Steven Thomas

Cannulation-VAThrough neck vessels(RCC artery and RIJV and or an additional vein)

Central cannulation

or

Cannulation of groin vessels

Access and return cannula sitesAccessReturnRAAortaFemoral VeinFemoral ArterySubclavian VeinAxillary arteryInternal Jugular VeinCarotid artery

Circuit

To be continuedPart 2 Next week