Regional Cerebral Oxygen Saturation Under General Anesthesia A Pilot Study

A total of 60 patients will be enrolled in the study: 20 each who receive surgery in beach chair position or Trendelenburg's position and 20 patients undergoing cardiac surgery. Regional cerebral oxygen saturation will be measured continuously during surgery. Duration and extent of deviations from individual baseline values will be recorded and detected deviations treated according to their clinically apparent cause (e.g. hypotension/hypovolaemia, anaemia, low cardiac output) in accordance with our standard operating procedures (SOPs). Patients are then followed up until the end of hospital stay or for a maximum of 10 days after surgery. Their level of cognitive function will be tested and compared to the data acquired before surgery to detect impairment, delirium or postoperative cognitive deficit (POCD). The purpose of this pilot study is to evaluate the design and conduct of a projected full scale observational clinical study.