Effects of ultrasound-guided stellate ganglion block on the balance of the supply and demand of cerebral oxygen during permissive hypercapnia in patients undergoing shoulder arthroscopy in beach chair position.

Permissive hypercapnia resulting from proper ventilation can significantly increase the rSO levels in patients who undergo shoulder arthroscopy in BCP, the effect of which was enhanced by SGB on patients' operation side to maintain well-balanced demand and supply of cerebral oxygen. (China Clinical Trial Registry, registration number ChiCTR2000033385, https://www.chictr.org.cn).