EXTRACORPOREAL MEMBRANE-OXYGENATION (ECMO) AS LUNG OR HEART ASSIST

Extracorporeal membrane oxygenation (ECMO) may serve as extracorporeal lung assist (ECLA) in patients with acute respiratory failure (ARF) o r as extracorporeal heart assist (ECHA) in patients with low output sy ndrome (LOS) after open heart surgery. From 1988 to 1992 seven patient s underwent ECMO in our hospital; four suffered from ARF and three fro m LOS. Various bypass techniques were employed. Two ARF patients, aged 58 and 18 years, had veno-venous bypass; in the latter, ECMO was rein stituted as a veno-arterial bypass one week after weaning. In a three- year-old boy, the ECMO outflow tubing was primarily connected to the p ulmonary artery and shortly afterwards relocated to the common carotid artery. In a 31-year-old man with ARF, and three LOS patients, a 56-y ear-old woman, and two men aged 68 and 70 years, ECMO was veno-arteria l with direct access to the ascending aorta. A heparin-coated system w as used, and all but one patient, who was treated with warfarin, recei ved a daily low dose of heparin, which was withdrawn after from one to nine days. Six patients were weaned off ECMO after 4.5 to 21 days. Th ree ARF patients recovered completely; the child died. In one LOS pati ent, ECMO was withdrawn due to a poor general condition. Two others we re weaned off ECMO and the intra-aortic balloon pump and the inotropic support was significantly reduced, but both died of multiple system o rgan failure. Although no firm conclusions can be drawn from these few case reports, the heparin-coated system used as ECLA appears promisin g, whereas ECHA seems to imply a poor prognosis in patients who are no t candidates for cardiac transplantation.