[Extracorporeal membrane oxygenation (ECMO) in adults]

Despite ongoing discussions, ECMO (extracorporeal membrane oxygenation) has become an important part of treatment options in acute lung injury and ARDS (acute respiratory distress syndrome) even in adults. On the other hand, none of the two RCT (randomized controlled trial) studies resulted in reduced letality of the artificial lung therapy when compared to convention treatment. Both authors concluded, that ECMO is not recommended in ARDS. Meanwhile experience with ECMO in adults is extensive in various institutions worldwide, exceeding 1000 patients by the end of 2001. Growing experience and improved technical equipment reduce the rate of technical complications substantially. However, for different reasons ECMO incidence in adults is progressively decreasing in recent years.    Inclusion and exclusion criteria vary among different ECMO centers. Potential reversibility of lung injury and persisting life-threatening gas exchange disorder under maximal conventional therapy are commonly seen as requirements for ECMO therapy. ECMO criteria are Murray lung injury score >3.5 (chest x-ray, PaO₂/FiO₂-index, static compliance C_stat, PEEP), Morel-classification >3 (chest x-ray, AaDO₂/FiO₂-index, C_stat, PEEP), AaDO2 >600mmHg, intrapulmonal shunt Q_S/Q_T >30%, and increase in extravascular lung water >15 ml/kg bodyweight.    Commonly accepted absolute contraindications are (1) severely consuming disorders with poor prognosis, (2) CNS damage with poor prognosis, (3) advanced chronic lung disorders, and (4) progressive multiple organ failure. Relative contraindications are immunosuppresion, active bleeding, age over 60 years, and days on mechanical ventilation.    In our experience, early contact to an ECMO reference center can optimise early identification of patients which benefit from ECMO, as well as treatment and transportation modalities, and improves outcome. Due to high technical and personal requirements and decreasing incidence in the adult sector, ECMO should be limited to a small number of reference centers with substantial experience in extracorporeal circulation.