VA ECMO
Definition
This is sudden loss of native cardiac output during ECMO support due to arrhythmia.
Effects
There will be loss of arterial pulsatility. The mean blood pressure may fall depending on the degree of ECMO support. Although chest compressions are not required, arrhythmias should be treated and reversed as soon as possible.
Identify rhythm
- Ventricular fibrillation or tachycardia
- Ventricular standstill
- Asystole
Response
Immediate
- Do NOT perform chest compressions
- Call for help. Contact ICU Consultant and ECLS Coordinator (in Hours)
- Assess blood pressure and circuit flow
- Establish sufficient circuit flow (usually greater than 4L/min) to support systemic perfusion
- Ensure oxygen on the blender is set to 100%
Examine for cause
- Exclude hyper/hypo-kalaemia
- Check body temperature
- Consider urgent ECHO to exclude cardiac compression/tamponade
Address cause and treat specific arrhythmia
- Defibrillation/Amiodarone for VF/VT
- NO adrenaline for asystole
After reversion assess and adjust ECMO blood flow settings, fresh gas flow, ventilator, inotrope and vasopressor support as required.
VV ECMO
Definition
This is sudden loss cardiac output and pulse pressure, VV ECMO does not support the systemic circulation.
Effects
In VV ECMO cardiac output is entirely provided by native cardiac function, during cardiac arrest there will be NO organ perfusions and oxygen delivery. Diminished venous return will cause recirculation and access insufficiency with CPR may occur.
Causes
- Ventricular fibrillation or tachycardia
- Ventricular standstill
- Asystole
- Hypoxia may trigger any of the above
Response
Immediate
- Commence resuscitation as per ACLS protocol
- Continue ECMO circuit flow in order to maintain blood oxygenation and avoid hypoxia and hypercapnia
- Ensure oxygen blender is set to 100%
- If there is access insufficiency during chest compression reduce pump speed by 500 rpm increments
- Turn up ventilator FiO2 to 100%
Seek and treat underlying causes in particular
- Hyper/hypokalemia
- Tension pneumothorax
- Cardiac tamponade
- Haemorrhage
- Air embolism
After ROSC, ECMO pump speed, ventilator settings and inotropes/vasopressor support may need to be adjusted