Noninvasive Neuromonitoring of Surgery of the Thoracic Aorta

For the purpose of this study, 30 patients undergoing aortic surgery via a median sternotomy (n=29; 97%) or left thoracotomy (n=1; 3%) and cardiopulmonary bypass with deep hypothermic cardiac arrest were recruited. All patients were operated under deep hypothermia and circulatory arrest, with optional selective cerebral perfusion during circulatory arrest. Active patient recruitment started from September 2007 and ended in May 2011. All patients were monitored with a bilateral fronto-temporal four channel abbreviated EEG, a bilateral frontal two-channel near-infrared spectroscopy, postoperative transcranial Doppler ultrasound evaluation of median artery circulation and postoperative biochemical neuromarkers. The study montage was set up by a dedicated research nurse, who also performed the transcranial Doppler measurements. The neuromonitoring data were not used at the time to guide therapeutic decisions, with the exception of near-infrared spectroscopy monitoring.