Respiratory failure and extracorporeal membrane oxygenation.

Conventional treatment of respiratory failure involves positive pressure ventilation with high concentrations of inspired oxygen. If adequate gas exchange still cannot be achieved extracorporeal membrane oxygenation (ECMO) may be an option. The general indication for ECMO for respiratory insufficiency is a reversible pulmonary disease, which cannot be managed by conventional means. ECMO is a modified heart-lung machine. Blood is withdrawn from a central vein in the patient and pumped through an artificial oxygenator back to the patient, either to a central artery (veno-arterial ECMO) or to a central vein (veno-venous ECMO). Total gas exchange can be achieved through the extracorporeal system, and the lungs do not have to be subjected to high-pressure ventilation. To date over 21,500 neonates have been treated with ECMO with an overall survival to hospital discharge of 76%. Meconium aspiration syndrome carries the highest survival (94%), whereas congenital diaphragmatic hernia on ECMO only has a survival of 52%. A total of 3500 pediatric patients (30 days to 18 years) have been treated with ECMO with a survival of 56%. Aspiration and viral pneumonia are the pediatric diagnoses with the highest survival rates. Randomized controlled studies have shown a significant advantage of ECMO with regard to survival in neonates. In the pediatric age group, nonrandomized studies have shown lower mortality in ECMO-treated patients.