Overview
As a simple auxiliary tool for lower extremity orthopedic surgery, tourniquet can effectively reduce intraoperative bleeding and ensure the clarity of the operative field, effectively shorten the operation time and improve the operation efficiency. The extensive use of tourniquets in lower extremity surgery will not only cause local paralysis, pain and other complications, but also bring about postoperative complications such as large drainage volume and deep vein thrombosis. Recent studies have found that tourniquet induced ischemia-reperfusion injury not only affects the local tissue structure and function of skeletal muscle, but also causes reperfusion injury in distant organs (such as heart, lung and brain). Therefore, improving tourniquet ischemia-reperfusion injury after knee replacement is of great significance to improve the quality of life of patients during the perioperative period. Therefore, the aim of this study was to investigate the effects of dexmedetomidine and tourniquet pretreatment on myocardial injury and brain injury caused by lower extremity ischemia-reperfusion.
Eligibility
Inclusion Criteria:
- Patients undergoing TKA under general anesthesia
- Voluntarily sign the informed consent
- ASA Grade I to III
- BMI 18-28 kg/m2
Exclusion Criteria:
- Congenital heart disease or history of cardiac surgery, heart conduction disease, frequent ventricular/atrial premature beats, atrial fibrillation and other serious arrhythmias
- Severe liver disease and kidney disease
- Temporary and permanent pacemaker implantation
- Patients with serious central nervous system diseases or serious mental disorders
- Recent history of sedation, antidepressant or opioid use
- Body mass index >35kg/m2
- Participants in other clinical trials within 1 month prior to study enrollment.