[Refractory hypoxia]

We report a case of refractory hypoxia in an 85 years old smoker patient, who is known for cardiac and pulmonary comorbidities. The whole clinical picture at the time of his admission to hospital was pointing to a cardiac failure or a pneumonia that were causing the respiratory insufficiency. Despite an optimal treatment which stabilised these conditions, the patient remained severely hypoxic, but with relatively few symptoms. The non response to the oxygen and the worsening of the oxygen saturation when changing from the lying to the sitting (or supine) position finally evoke the syndrome of platypnea-orthodeoxia caused by a cardiac right to left shunt; that diagnosis was confirmed by a cardiac ultrasound with contrast which revealed an important inter-auricular shunt. The patient didn't wish to undertake the curative treatment (shunt closure).