[Refractory hypoxemia caused by transient opening of the foramen ovale after pneumonectomy].

A patient with bronchogenic cancer underwent right pneumonectomy. Surgical and infectious criteria were normal during the postoperative period when immediate postoperative severe hypoxeamia occurred. Pure oxygen only incompletely corrected the situation. Transoesophageal echocardiography with injection of microbulles for contrast imaging demonstrated a right-left shunt due to an open foramen ovale. Reopening the foramen ovale is rare but well documented complication of pneumonectomy. The pathogenics is still debated since hyperpressure in the right atria usually is not present. Echocardiography with contrast test is the best means of making the diagnosis.