Positioning of the patient with hyperacute large artery ischemic stroke (IS) is an important, yet understudied aspect of care that could impact the course of treatment and ultimately clinical outcome. Positioning with the head of bed (HOB) at 0-degree has been shown in small studies to increase cerebral blood flow across arterial occlusion in hyperacute large artery IS, leading to clinical improvement in stroke symptoms. However, this position is believed to increase the risk of aspiration pneumonia. In this randomised clinical trial, the investigators aim to evaluate whether use of 0-degree HOB positioning is associated with clinical stability in hyperacute IS. Investigators hypothesise that patients with large artery occlusions placed in a 0-degree HOB position will experience less early neurologic deterioration within the first 24 hours, than those in the 30-degree or more HOB elevation group. The study aims to confirm the safety of 0-degree-HOB positioning in a large, generalizable sample of hyperacute large artery IS patients. In this randomised trial, patients presenting to the study centers and eligible for intravenous thrombolysis, with (if presenting within 4.5 hours of symptom-onset) or without (presenting between 4.5 to 16 hours of symptom-onset) mechanical thrombectomy. Eligible patients would be randomised to either a zero-degree HOB or an HOB of 30-degree or more. Impact of HOB position on neurological status would be evaluated with serial NIHSS scores. Cerebral hemodynamics would be monitored by transcranial Doppler ultrasonography. Validated criteria would be used to diagnose pneumonia. Functional outcome would be measured by modified Rankin scale (mRS) where the score of 0-2 describe good functional recovery. SPSS version 20 would be used to analyse the data. The trial would provide clinical and hemodynamic data to determine the optimal HOB position in patients with large artery acute ischemic stroke.