Patient-Centered Outcomes after General and Spinal Anesthesia

General anesthesia, a state of reversible unconsciousness, is one of the most important advances in medicine, enabling more than 300 million people annually to safely undergo invasive procedures. Concern has emerged that the effects of general anesthesia may not be transient, especially in patients with underlying neurologic disorders. In 1955, on the basis of a retrospective study entitled "Adverse Cerebral Effects of Anaesthesia on Old People,"1 Bedford postulated that anesthetic drugs might damage the brain through synaptic depression and by decreasing cerebral oxygen uptake. He concluded that "operations on elderly people [under general anesthesia] should be confined to unequivocally necessary . . .