RecruitingDevice studyEffects of Transcutaneous Vagal Nerve Stimulation on Post-Surgical Return to Consciousness, Delirium, and DepressionThis study will examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) can help restore consciousness in patients in the operating room and the Post Anesthesia Care Unit (PACU). The study will also investigate if tcVNS can expedite discharge from the PACU and examine whether tcVNS administerd in the PACU helps reduce delirium and depression after surgery. The study will also evaluate whether tcVNS speeds cognitive recovery from emergence of anesthesia and surgery.