Unusual severe hypoxemia due to unilateral pulmonary edema after conventional cardiopulmonary bypass salvaged by veno-venous extracorporeal membrane oxygenation: a case report

BACKGROUND: We report a case in which veno-venous extracorporeal membrane oxygenation (V-V ECMO) saved the life of a patient who developed severe hypoxemia due to unusual unilateral pulmonary edema (UPE) after cardiopulmonary bypass (CPB). CASE PRESENTATION: A 69-year-old man underwent aortic valve replacement and coronary artery bypass grafting. Following uneventful weaning off CPB, he developed severe hypoxemia. The ratio of arterial oxygen tension to inspired oxygen fraction (PaO(2)/FiO(2)) decreased from 301 mmHg 5 min after CPB to 42 mmHg 90 min after CPB. A chest X-ray revealed right-sided UPE. Immediately established V-V ECMO increased PaO(2)/FiO(2) to 170 mmHg. Re-expansion pulmonary edema (REPE) was likely, as the right lung remained collapsed during CPB following the accidental opening of the right chest cavity during graft harvesting. CONCLUSIONS: V-V ECMO was effective in improving oxygenation and saving the life of a patient who had fallen into unilateral REPE unusually developing after conventional CPB.