[Non-invasive cerebral oximetry monitoring in percutaneous cardiac valvular implantations: two cases report].

Cerebral oximetry non-invasive technology is based on cerebral tissue oxygen saturation (StcO2) measure in microcirculation, through near-infrared spectroscopy (NIRS)). As a result, cerebral oximetry (StcO2) is a mixed oxygen saturation parameter between de-oxide and oxide hemoglobin witch estimates a value between arterial (SaO2) and jugular venous saturation (SvjO2) under physiologic conditions. Complementary to the arterial oxygen saturation measured by pulse oximetry, cerebral tissue oxygen saturation reflects regional cerebral metabolism and the balance of local cerebral oxygen supply and demand. In this article, the authors report two clinical cases, the first case of a 79 year old man, submitted to percutaneous aortic valve bioprothesis femoral implantation, complicated by a stroke event, expressed by cerebral hypoxia in StcO2 monitorization on the left hemisphere and clinical motor deficit evidence, and the second one a 73 year old man, ASA III, submitted to percutaneous aortic valve bioprosthesis subclavian implantation procedure, where no complications were decribed and haemodymic and StcO2 stability was noticed.Given the clinical evidence on the reported cases, StcO2 monitorization revealed to be a relevant and usefull tool, in order to identify cerebral tissue hypoxia in the first case, as well as reflecting the adequate balance of local cerebral oxygen supply and demand, in the later.