Normal Saline Infusion for Stroke After Intravenous Thrombolysis (NS-STAR)

Inclusion Criteria： Acute ischemic stroke (AIS) Age 18-80 years Pre-stroke mRS≤1 Onset-to-needle time≤4.5 hours Treated with alteplase Initial diagnosis of penetrating artery disease, large artery atherosclerosis (LAA) inducing parent artery (plaque or thrombus) occluding penetrating artery and LAA inducing hypoperfusion defined by Chinese ischemic stroke subclassification (CISS) system Sign the informed consent Exclusion Criteria： Severe AIS, including NIHSS score>20 in dominant hemisphere infarction, or NIHSS score>15 in non-dominant hemisphere infarction, or NIHSS consciousness score >1 Massive infarction, characterized by infarction area larger than 1/3 of the effected middle cerebral artery (MCA) territory and/or the cerebellum territory presented in admitted CT or MRI Initial diagnosis of LAA inducing artery-to-artery embolism, cardiogenic stroke, other etiologies and undetermined etiologies defined by CISS system Intention to undergo endovascular treatment Intention to undergo antiplatelet drugs within 24 hours after IVT, such as aspirin, clopidogrel, ticagrelor, cilostazol and tirofiban Allergy to alteplase Arterial puncture at a non-compressible site within previous 7 days, major surgery within previous 14 days, sever trauma, gastrointestinal or urinary tract bleeding within previous 21 days Cerebral infarction or myocardial infarction within previous 3 months, previous intracranial haemorrhage (ICH) including parenchymal haemorrhage, intraventricular haemorrhage, subarachnoid haemorrhage, subdural/external haematoma, etc Severe brain trauma, intracranial or intraspinal surgery within previous 3 months or known malignant intracranial neoplasm, giant intracranial aneurysm or arteriovenous malformation Persistent systolic blood pressure≥180mmHg or diastolic blood pressure≥100mmHg Admitted blood glucose<2.8mmol/L or >22.22mmol/L Defect in coagulation, for example, current use of oral warfarin with an international normalised ratio>1.7, or prothrombin time>15s, or heparins during the last 48 hours, or use of direct thrombin inhibitors or direct factor Xa inhibitors during the last 48 hours or with an elevated activated partial thromboplastin time Platelet count<100×109/L Stroke mimics, such as seizure and hysteria Brain haemorrhage identified by CT or MRI Any terminal illness such that patients would not be expected to survive>1 year Pregnant women or nursing mother Poor compliance Participating in other clinical trials within previous 3 months.