ECMO UPDATE

Sam Phillips

ECMO Overview

• What is it?

• SCGH Inclusion/Exclusion criteria

• What – equipment/staff

• What – is the process from activation

• What – differences of an ECMO resus vs conventional resus?

• Future

ELSO ECMO Definition

• ECMO (Extracorporeal Membrane Oxygenation)– is defined as the use of a cardiopulmonary bypass circuit for

temporary life support for patients with potentially reversiblerespiratory and/or cardiac failure failing to respond to maximal medical therapy.

• E-CPR (Extracorporeal Cardiopulmonary Resuscitation)– is the initiation of bypass during resuscitation of the arresting patient.

Two types of ECMO

• VV = Veno-venous

• VA = Veno-arterial

VA ECMO/E-CPR

• Performed in the ED setting.• Provides both respiratory and haemodynamic support.• Venous drainage from the right atrial inlet via the CFV and

infusion into the iliac artery via the FA.• Establishment of the circuit is therefore retrograde.

VA ECMO

The Circuit

SCGH Indications for ED ECMO

Currently this is an in hours service (0800-1700) however patients who meet criteria out of hours could be discussed with cardiothoracics/ICU.

Patients with out-of-hospital cardiac arrest which is refractory to standard ACLS treatment AND:

• The patient meets all of the following criteria:– Age 16-65 years– Likely primary cardiac, respiratory or other reversible cause.– Witnessed arrest.– CPR commenced within 10 minutes of arrest.– Duration of arrest (collapse to arrival in ED ) <45 mins.– No major co-morbidities that would preclude return to independent living.

Absolute Contraindications

• First checked rhythm is asystole• ETCO2 <10mmHg in ED• Limitations of care or do-not-resuscitate orders in place.• Terminal illness due to malignancy/chronic disease• Significant neurologic/neuromuscular impairment• Major trauma/active haemorrhage• Known symptomatic chronic organ failure

– Multiple past coronary revascularisations– Cirrhosis (jaundice, ascites, encephalopathy)– ESRF (dialysis)– Cardiomyopathy (VAD, inotropes or EF <35%)– Chronic lung disease (NYHA III or IV)– Severe pulmonary arterial hypertension

• Pending the creation of a code ECMO call, cardiothoracics/perfusionist/ICU/ED USS consultant/ED duty consultant +/- cardiologist should be informed as early as possible if a patient is considered a probable candidate prior to or soon after arrival.

• NB The final decision for suitability will be determined on a case by case basis using the above inclusion/exclusion criteria based on the assessment of two consultants.

E-CPR Requirements

• In addition to the standard ACLS, there are two key components of E-CPR, which must be provided concurrently;

1. External chest compression using the Lucus machine, and

2. Rapid percutaneous cannulation using small cannulae (15F-17 Fr arterial, 17-21Fr venous) and connection to the pre-primed ECMO machine.

NB Previously patients were also given peri-arrest cooling with a rapid infusion of 40ml/kg of ice cold saline however the RINSE Trial demonstrated no benefit and potential for harm with reduced ROSC rates in those with an initial shockable rhythm and no trend towards improved outcomes at discharge.

Steps

1. Identify ECMO suitable patient.2. Activate team (0800-1700)

– ED duty consultant, US consultant, 1-2 intensivists, cardiothoracic surgeon, perfusionist, ICU/ED ECMO certified nurse.

– Plus if likely to go to cath lab – cardiologist, cardiac anaesthetist.

3. Continue LUCAS compressions.4. US guided femoral lines – venous and

arterial (convert to 15-17Fr art and 19 -21Fr venous) (training required).

5. Attach pre-primed circuit (training required).

6. Optimize and treat potential causes.7. Transfer to cath lab/theatre for

definitive treatment.

Staff and Roles required for E-CPR

• 10 staff in total who have predetermined roles.

1. ED Consultant – team leader runs resus.2. ED Reg – ensures patient is intubated early and hand ventilates until patient on ECMO.3. 4x ED nurses

Airway - assists with airway management. Circulation – transfers to ED defibrillator and continues Lucas compressions. Drug – prepares adrenaline infusion and runs at 50micrograms/min during compressions

- draws up sedation (midazolam) and muscle relaxant (rocuronium) Scribe

4. ED USS consultant/ICU consultant opens ECMO pack and prepares cannulation equipment, images FA and FV and places guidewires. If perfusionist present but no cardiothoracics surgeon then proceeds to dilation and placement of cannulae with assistance

from a second ED USS/ICU consultant.

5. Cardiothoracics surgeon if perfusionist arrives with the CT surgeon then the CT surgeon gowns and gloves and proceeds to dilation, placement of

femoral cannula and connection to the circuit with assistance from the ED USS consultant/ICU consultant.

6. ED USS or ICU consultant - images IVC and aorta to determine correct placement of guide-wires pre dilation.

7. Perfusionist – checks primed ECMO circuit and connects cannulae . Runs ECMO flow at 3L/min and oxygen flow at 3L/min.

SCGH ED ECMO BOXCHECKLIST

• ECMO Role Cards• Gloves, gowns and masks x 3• Major Anaesthetic Pack x 1• Gauze• Betadine cleaning solution• Bi-femoral Drape (Lifemed Patient Drape Universal Fem. Angiography) x 2• Ultrasound Probe Cover Long x 2• Medtronic cannula and dilator sets:

– single stage arterial 17 Fr x1 (15 Fr available in compactors)– multistage venous 21 Fr (19 Fr available in compactors)– additional dilator sets– additional guide wires (1 & 1.5m)

• Backflow cannula 7-9 Fr (Super Arrowflex Percutaneous Sheath Introducer Set)

• Mosquito forceps 12.5cm x 4• Sterile clamps 18cm x 4• 60ml Syringe with nozzle x 2• 20000U of heparin (10000U/ litre)• 2L normal saline• 8L Bowl Sterile (for mixing saline and heparin)• Griplok dressings (universal medium size) x 4• Tube cutting scissors x 2• Cable ties x 8

Steps in Femoral Cannulation for VA ECMO

Step 1• Cannulating the femoral vein and contralateral

femoral artery under direct ultrasound guidance.

Step 2• Check placement of wires with ultrasound by a

second consultant.

Step 3• Progressive dilation of each cannula up to 21Fr

(venous) and 17 Fr (arterial).• Requires 2 operators

– One making incision and dilation while the other ensures the guidewire continues to slide freely.

Step 4• Checking positioning of the cannula before

commencing ECMO.– Arterial cannula in iliac artery and venous cannula sitting in the RA

inlet.

Step 5• Ensuring there is no air in either the arterial or

venous lines and ECMO circuit before connection to the circuit.

VA ECMO Cannulation

Differences between a conventional vs ECMO resus

Pre-cannulation (before skin prep)– Treat as per standard ALS algorithm using the LUCUS for chest compressions.– Run through ECMO inclusion/exclusions.– Activate ECMO call if suitable candidate (if haven’t done so already).– Get ECMO box out and commence setup for cannulation.– Expose and shave both groins.– Attempt to determine underlying aetiology and likely disposition ie cathlab/embolectomy etc.

Cannulation phase (from skin prep)– Cease standard ALS algorithm.– Hand ventilate via ETT.– “Cannulation phase = No more defibrillation”.– Continue LUCUS but stop (max 1min) during needle puncture and guidewire insertion.– Commence an adrenaline infusion at 50ml/hr ie 50mcg/min.– Achieve bi-femoral access ideally 21Fr venous on the patient’s right and a 17Fr arterial cannula on the

left.– Connect to the ECMO circuit ensuring no air in circuit.– STOP resuscitation if not on ECMO by 90 mins post initial arrest (target <60mins).

The Future

• SCGH be the cardiac arrest/E-CPR centre for Perth?• Have a *55 number similar to stroke calls and STEMIs to activate the SCGH

ECMO team.• Initially offer 0800-1700 E-CPR service with potential to expand in the

future.• Have ongoing ECMO simulation team training.• Participate in the ongoing E-CPR research.

– multi-centre clinical trial ‘2CHEER’ involving St Vincent’s, Royal Prince Alfred and Sydney hospital currently underway.