Sodium Sivelestat With Mechanical Thrombectomy for Acute Stroke: A Pilot Study

Inclusion Criteria: 1. Symptoms and signs consistent with focal ischemia in the anterior or posterior circulation; 2. Large vessel occlusion of the anterior or posterior circulation (internal carotid artery, M1/M2 segment of the middle cerebral artery, vertebral artery, or basilar artery) confirmed by CTA/MRA/DSA; 3. Undergoing mechanical thrombectomy; 4. Age ≥18 years, both male and female; 5. Pre-stroke modified Rankin Scale (mRS) score ≤1; 6. Time from symptom onset to thrombectomy ≤24 hours, including wake-up stroke or unwitnessed stroke; symptom onset is defined as the "last known well" (LKW); 7. National Institutes of Health Stroke Scale (NIHSS) score ≥6 at admission; 8. ASPECTS ≥3 for anterior circulation occlusion, or pc-ASPECTS ≥6 for posterior circulation occlusion; 9. Written informed consent provided by the patient or their legal representative. Exclusion Criteria: 1. Simultaneous acute occlusion of both anterior and posterior circulation or bilateral hemispheric large vessel occlusions; 2. Complete clinical recovery at the end of EVT procedure; 3. Arterial dissection or intraoperative hemorrhage indicated by post-thrombectomy DSA; 4. Sedated and intubated patients without baseline NIHSS assessment; 5. Seizure at stroke onset interfering with baseline NIHSS assessment; 6. Bilateral fixed dilated pupils; 7. Severe allergy or absolute contraindication to sodium sivelestat; 8. Severe allergy or absolute contraindication to iodinated contrast agents; 9. Systolic blood pressure \>185 mmHg or diastolic blood pressure \>110 mmHg, uncontrolled despite antihypertensive therapy; 10. Blood glucose \<50 mg/dl (2.8 mmol/L) or \>400 mg/dl (22.2 mmol/L); 11. Platelet count \<50×10⁹/L; 12. Congenital or acquired bleeding diathesis, coagulation factor deficiency, or current use of oral anticoagulants with INR \>1.7; 13. Severe renal impairment, defined as serum creatinine \>3.0 mg/dl (265.2 μmol/L), GFR \<30 ml/min, or requirement for hemodialysis/peritoneal dialysis; 14. Inability to complete 90-day follow-up (e.g., no fixed residence, overseas patient); 15. Suspected vasculitis or septic embolism; 16. Suspected aortic dissection; 17. Pre-existing neurological or psychiatric disorders interfering with stroke assessment; 18. Pregnancy or lactation; 19. Confirmed rheumatic/autoimmune disease with long-term use of immunosuppressants or corticosteroids; 20. Current treatment with chemotherapy or other immunomodulatory agents (e.g., recombinant human granulocyte colony-stimulating factor, Xuebijing, ulinastatin, etc.); 21. Participation in another clinical trial that may interfere with study outcomes; 22. Any other condition that investigators deem unsuitable for participation or that may pose significant risk to the patient.