A randomized controlled trial of pre-elevation posture in the prevention of arthroscopic subsyndromal delirium in the elderly: effects on cerebral oxygenation, carotid blood flow, and inflammatory response

INTERVENTION: Semi‐recumbent position group:Anesthesia induction was performed by elevating the upper body by 30°.;Supine position group:Anesthesia induction in supine position; CONDITION: Delirium PRIMARY OUTCOME: Incidence of postoperative subsyndromal delirium (SSD);Incidence of hypotension;Change in right jugular venous blood flow;Fluctuations in inflammatory markers S100ß and TNF‐a;Minimum cerebral oxygen saturation; SECONDARY OUTCOME: Time to emergence;Vasopressor dosage; INCLUSION CRITERIA: 1. Patients scheduled for elective arthroscopic shoulder surgery under general anesthesia with tracheal intubation; 2. Aged >=60 years; 3. ASA I‐III grade; 4. Normal Mini‐mental State Examination (MMSE) score: illiterate >= 17, primary school >=20, secondary school and above >=24; 5. Signed informed consent form.