To investigate whether limb remote ischemic preconditioning (LRIP) could safely decrease the incidence of delirium in elderly patients after non-cardiac surgery.

Remote ischaemic preconditioning may confer the cytoprotection in critical organs. We hypothesized that limb remote ischemic preconditioning (RIPC) would safely decrease the incidence of delirium in elderly patients after non-cardiac surgery.The primary outcomes included the incidence of delirium in the first 7 days after surgery using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) scale.The quality of recovery over a 6-month period was evaluated as well.Secondary endpoints included length of stay in the hospital after surgery (from day of surgery to hospital discharge), occurrence of non-delirium postoperative complications, and all-cause 6-month mortality.

Inclusion Criteria:

• elderly patients received elective non-cardiac surgery with general anesthesia
• anticipated surgery time > 2 hours

Exclusion Criteria:

• age < 65 years old
• Acute coronary syndrome or myocardial infraction within 3 months
• Chronic obstructive pulmonary emphysema
• Serious hepatic dysfunction (Child-Pugh class C)
• serious renal dysfunction (undergoing dialysis before surgery)
• Ejection fraction less than 40%
• Poor pulmonary function (PaO2 <60mmHg)
• Preoperative history of schizophrenia, epilepsy, Parkinsonism, or myasthenia gravis
• Inability to communicate in the preoperative period (coma, profound dementia, or language barrier)
• Brain injury or neurosurgery