to detect the effects of RIC on stroke-induced immunodeficiency and inflammation response in acute ischemic stroke patients

Remote ischemic conditioning, consisting of several brief cycles of intermittent ischemia-reperfusion of the arm or leg, may potentially confer systemic protection against prolonged ischemia in a distant organ. Numerous reports have confirmed its strongest endogenous neuroprotection against brain injury after stroke, of which the immune mechanisms are majorly involved in RIC. At the same time, the inflammation response plays a great role in stroke development, which may expand the infarct area. Stroke-induced immunodeficiency can potentiate stroke-associated pneumonia, which is an important cause of death after strokes. In this study, the investigators will assess the effect of RIC on stroke-induced immunodeficiency and inflammation response in AIS patients.

Inclusion Criteria:

• Age≥18 years old;
• Confirmed diagnosis of acute ischemic stroke(AIS) with onset of symptoms within 48h at recruitment;
• NIHSS score: ≤15;
• Prestroke modified Rankin Scale(mRS) ≤2;
• subject or his or her legally authorized representative was able to provide informed consent.

Exclusion Criteria:

• uncontrolled hypertension (defined as systolic blood pressure ≥200 mmHg);
• participation in another device or drug trial simultaneously;
• any vascular, soft tissue, or orthopedic injury (eg, superficial wounds and fractures of the arm) that contraindicated unilateral arm ischemic preconditioning;
• peripheral vascular disease (especially subclavian arterial and upper limb artery stenosis or occlusion);
• Women who have a positive pregnancy test;
• History of malignancies;
• Using remote ischemic conditioning within the preceding 1 week;
• known infection at admission;
• a history of infection or the use of antibiotics, immunosuppressants, or steroids within the preceding 3 months.
• Other conditions are not suitable for this trial (evaluated by researchers)