Overview
The SHIELD trial is a single-center, randomized, controlled, parallel-group, single-blinded clinical trial investigating whether performing RIPC one day before surgery-compared to not performing RIPC-reduces postoperative neuronal injury, as reflected by the maximum serum NfL concentration within the first 2 postoperative days, in non-cardiac surgery patients at risk for postoperative delirium.
Eligibility
Inclusion criteria:
- patients (≥50 years) scheduled for elective non-cardiac surgery with general anesthesia
- patients at risk for postoperative delirium, defined as the presence of ≥2 of the following established risk factors: age ≥65 years, American Society of Anesthesiologists physical status classification of ≥III, Charlson Comorbidity, planned surgical duration \>180 minutes, polypharmacy (regular intake of more than five medications), symptoms of depression (Patient Health Questionnaire-9 ≥10 points)
Exclusion criteria:
- patients in whom RIPC cannot be safely applied due to relevant peripheral arterial disease (defined as Fontaine stage ≥II), lymphedema, recent upper-arm surgery, trauma, or skin lesions at the arm
- patients with acute coronary syndrome (within the past month)
- patients with surgery in the previous month
- patients with intracranial surgery
- patients with pre-existing delirium
- patients with severe cognitive impairment preventing reliable delirium assessment
- patients with current treatment with sulfonamides due to potential interference with ischemic preconditioning mechanisms
- patients with previous participation in the SHIELD trial
