ECMO support is a specialised form of mechanical circulatory and respiratory support used in intensive care units for life-threatening heart or lung failure. The primary goal of ECMO is not to cure underlying organ disease, but to maintain systemic blood flow and gas exchange when standard mechanical ventilation or pharmaceutical therapies are insufficient. By routing blood through a modified heart-lung machine outside the body, ECMO reduces the workload on damaged tissues, preserving vital organ function while clinical teams treat the primary medical condition.

The ECMO procedure begins with cannulation under sterile conditions in an intensive care unit, operating theatre, or cardiac catheterisation laboratory. Clinicians select vascular access sites, typically the femoral vein, internal jugular vein, or femoral artery. Vascular access is achieved using Seldinger techniques with ultrasound guidance or direct surgical cutdown. After systemic heparinisation to prevent clotting, large-bore flexible plastic tubes called cannulae are advanced into central blood vessels. The cannulae are connected to a primed ECMO circuit consisting of a blood pump, a polymethylpentene membrane oxygenator, a heat exchanger, and continuous line sensors. Once connected, blood flow is slowly initiated and increased until target gas exchange or cardiac output support is achieved. The clinical team secures the cannulae with multiple sutures and protective dressings, continuously monitoring system pressure gradients, circuit flow rates, and biological blood parameters.

Clinical evidence demonstrates that ECMO support provides crucial life-sustaining gas exchange and circulatory support when mortality risk exceeds 80% under standard mechanical ventilation or high-dose vasopressor therapy (ELSO Guidelines 2021). Key benefits include immediate correction of severe refractory hypoxaemia and hypercapnia, significant reduction in ventilator-induced lung injury by allowing ultragroup ultra-protective lung ventilation, stabilization of systemic blood pressure, preservation of end-organ perfusion (kidney, liver, brain), and creation of a therapeutic bridge to native organ recovery or organ transplantation.

Recovery following ECMO support unfolds across immediate, medium, and long-term clinical phases. The immediate recovery phase takes place in the intensive care unit over 7 to 21 days, during which decannulation sites heal, mechanical ventilation is gradually reduced, and physical therapy commences in bed. Medium-term recovery spans 1 to 3 months, involving progressive physical rehabilitation to rebuild muscle mass lost during critical illness. Long-term recovery extends over 6 to 24 months, with specialized follow-up evaluating pulmonary function tests, cardiac ejection fraction, physical endurance, and cognitive performance through structured post-intensive care syndrome monitoring.

ECMO support treats severe, life-threatening conditions where conventional medical management fails to support lung or heart function. Indications include severe acute respiratory distress syndrome (ARDS) from viral or bacterial pneumonia, massive pulmonary embolism, acute myocardial infarction with cardiogenic shock, post-cardiotomy failure to wean from cardiopulmonary bypass, acute fulminant myocarditis, severe septic shock with secondary cardiac depression, and accidental severe hypothermia. It is also used as a bridge to heart or lung transplantation or mechanical circulatory support devices.

Preparation for ECMO support involves rapid multidisciplinary clinical assessment, baseline laboratory evaluation, diagnostic bedside ultrasound, and vascular mapping. Clinicians evaluate coagulation status, including prothrombin time, international normalised ratio, activated partial thromboplastin time, fibrinogen levels, and platelet count. Blood group typing and crossmatching are performed immediately to secure packed red blood cells and fresh frozen plasma. Echocardiography is performed to assess baseline cardiac contractility, cardiac valve competence, and underlying structural cardiac pathology. Ultrasound imaging of the femoral and jugular vessels is conducted to confirm vessel patency and anatomical size prior to cannula insertion. Systemic anticoagulation is initiated with an intravenous heparin bolus prior to vascular cannulation unless active severe haemorrhage is present.

Complications associated with ECMO support are stratified into common mild issues, serious moderate complications, and critical life-threatening risks. Common complications include minor bleeding around vascular access cannula sites, localized subcutaneous haematomas, transient thrombocytopenia, and low-grade haemolysis. Serious complications include major gastrointestinal or intracranial haemorrhage, vascular access site thrombosis, surgical site infections, heparin-induced thrombocytopenia, and mechanical circuit failure or oxygenator failure. Critical life-threatening risks include fatal stroke (ischaemic or haemorrhagic), limb ischaemia leading to amputation in venoarterial configurations, systemic air embolism, persistent acute kidney injury requiring continuous renal replacement therapy, and overwhelming multi-organ failure.

The clinical journey for ECMO support begins with emergency evaluation and multidisciplinary triage in the intensive care unit. Once cannulation sites are selected, vascular access is established via surgical cutdown or ultrasound-guided percutaneous access. During the support phase, patients are continuously monitored for haemodynamic stability, anticoagulation parameters, and organ recovery. The weaning phase involves gradually reducing ECMO flow rates to test native cardiac or pulmonary strength before decannulation. Post-ECMO care focuses on physical rehabilitation, decannulation site monitoring, and long-term neurodevelopmental or physical follow-up.