VVECMO

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a form of temporary life support for severe respiratory failure when conventional mechanical ventilation cannot maintain adequate oxygenation or carbon dioxide removal. Blood is drawn from the venous system, circulated through an extracorporeal circuit with a pump and an oxygenator, and returned to the venous circulation, typically into the right atrium. Gas exchange occurs across the membrane oxygenator, with the sweep gas and the inspired oxygen determining CO2 removal and O2 delivery.

Circuits include a pump, oxygenator, heat exchanger, and tubing. Cannulation is usually via a right internal jugular dual-lumen cannula or separate femoral and jugular cannulas; approaches may be percutaneous or surgical. Flow rates are set to provide adequate oxygen delivery and CO2 removal; sweep gas controls CO2 clearance, and arterial oxygen content is set by FiO2. Anticoagulation is commonly used to prevent circuit thrombosis, balanced against bleeding risk.

Indications include severe, potentially reversible respiratory failure such as ARDS from pneumonia or viral infections when lung-protective ventilation is insufficient. VV-ECMO is performed in experienced centers with multidisciplinary teams. It is not indicated for primary cardiac failure or irreversible multi-organ failure, and contraindications include conditions with poor prognosis or high bleeding risk.

Management involves monitoring lung recovery, hemodynamics, anticoagulation, infection control, and plans for weaning and decannulation as gas exchange improves. Complications can include bleeding, thrombosis, infection, hemolysis, cannula malposition, or vascular injury. Outcomes depend on underlying disease and center experience but survival in appropriately selected adults can be substantial.