Effect of Cerebral Oxygen Saturation Monitoring on POCD of Elderly Patients Undergoing Shoulder Arthroscopy

In this group, intraoperative monitoring of cerebral oxygen saturation will be used. When the cerebral oxygen saturation decreased by 20% \~ 25% compared with the baseline for 300 seconds without improvement, or the cerebral oxygen saturation decreased by 25% \~ 30% compared with the baseline for 180 seconds without improvement, intervention would be carried out. When the cerebral oxygen saturation decreased by 30% compared with the baseline, immediate intervention would be carried out. The intervention measures were intravenous administration of deoxyepinephrine 50 \~ 100 μg or ephedrine 5 \~ 10mg, which can be administered multiple times until the cerebral oxygen saturation reaches more than 80% of the baseline.