Extracorporeal Membrane Oxygenation in Adults - Variants, Complications during Therapy, and the Role of Radiological Imaging.

Extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) as respiratory and circulatory assist therapies are gaining in importance in the treatment of critically ill patients. Depending on the place of cannulation - veno-venous for ECMO and veno-arterial for ECLS - distinct changes in hemodynamics will occur. In this review we describe the different types of ECMO and ECLS systems, the typical cannula placement and frequent complications under therapy. The most suitable imaging modalities will be presented and typical hemodynamic pitfalls in contrast-enhanced computed tomography or angiography will be elucidated.  The review is based on a literature search in PubMed with the terms "ECMO" and/or "ECLS" and/or "extracorporeal life support" and/or "imaging" and/or "complications". Statistical data was taken from the ECMO register of the "Extracorporeal Life Support Organization (ELSO)".  Critical illness- and therapy-associated complications are common so that imaging, particularly computed tomography, becomes increasingly important. Following veno-venous cannulation in ECMO, the normal sequential blood flow is preserved, so that no contrast enhancement irregularities should be expected when the right timing and an adequate amount of contrast agent are selected. After veno-arterial cannulation in ECLS, different artifacts like pseudo-filling defects, pseudomembranes and irregular/low contrast enhancement of heart and pulmonary vessels can be found, depending on the site of cannulation and the residual cardiac function. · Cannula placement is usually documented by radiography.. · Computed tomography is appropriate in the face of inconclusive cannula placement and probable complications.. · In veno-venous ECMO, no contrast enhancement artifacts are to be expected.. · Veno-arterial ECLS leads to pseudo-filling defects, pseudomembranes and irregular contrast enhancement of heart and pulmonary vessels.. · Beck L, Burg MC, Heindel W et al. Extracorporeal Membrane Oxygenation in Adults - Variants, Complications during Therapy, and the Role of Radiological Imaging. Fortschr Röntgenstr 2017; 189: 119 - 127.