Effects of surgical position on cerebral oxygen saturation and its regulation

Abstract

Background Regional cerebral oxygen saturation (rSO2) is an important parameter to evaluate cerebral perfusion, brain metabolism, brain oxygen supply and demand, and to prevent postoperative neurological complications. Cerebral perfusion and rSO2 vary with different surgical positions. Objective This article reviews the characteristics and underlying mechanisms of the relationship between rSO2 values and surgical positions, and the clinical practices in preventing intraoperative brain ischemia and hypoxia in patients with different surgical positions. This review aims to provide an insight for the prevention of neurological complications associated with general anesthesia. Content Real-time quantification of oxygen supply and consumption is essential in operative monitoring. Insufficient blood and oxygen supply in the brain during operation may result in ischemia, hypoxia, and even postoperative cognitive dysfunction, depression and stroke. Monitoring rSO2 and maintaining it in normal ranges can prevent these postoperative complications. The rSO2 decreases in some surgical positions, including beach chair position, prone position, lateral position, and Trendelenburg position. In these situations, efforts should be made to maintain normal cerebral perfusion pressure and to improve lung ventilation. Trend Using near infrared spectroscopy to monitor rSO2 is valuable to efficiently recognize the adverse effects of altered surgical positions on cerebral oxygen supply, and to timely make efforts to prevent postoperative complications. Key words: Cerebral oxygen saturation; Surgical position; Anesthesia management