Background: Stroke is a leading cause of mortality among patients presenting to the emergency department with Acute Ischemic Stroke being a significant contributor. Clinical guidelines emphasize the importance of adequate hydration in management of stroke. Dehydration may impair cerebral oxygen delivery and worsen clinical outcome in patients with acute ischemic stroke (AIS). Elevated blood urea nitrogen to creatinine ratio (BUN/Cr) as a marker of dehydration has been associated with poor clinical outcome in emergency department (ED) patients presenting with AIS. Dehydration also attributes to the increased rate of infections and length of hospital stay in patients with AIS. Objectives: To study the association of dehydration markers BUN/Creatinine ratio, plasma osmolality, haematocrit and Caval Index with the outcome in patients with Acute Ischemic Stroke in terms of Mortality and Morbidity (Length of Stay in Hospital) and to correlate the hydration status with the disease progression by using NIHSS score and Modifies Rankin score. Methods and study design: The study was conducted from January 2017 till January 2018 over a period of 1 year. It was a Prospective observational cohort study. Patient included in the study were followed up at 3 and 30 days as per the questionnaire designed for the study after the approval by scientific and ethics committee of the institute. For the purpose of statistical significance we will recruit 64 patients as per the inclusion & exclusion criteria of the study. Data collection was done as per the approved data collection forms for the purpose of study. Patient’s initial, BUN, Creatinine, Urea, Sodium, blood glucose, Caval index (optional) and clinical status was be collected as per NIHSS and Modified rankin scale. The patient was followed up during their duration of stay in the hospital on 1st, 2nd and 3rd day. During the follow up period patients was followed for progression and outcome based on clinical parameters and the mentioned scores. Results and Conclusion: In conclusion, though we were able to associate plasma osmolality and BUN/Creatinine ratio with mortality, length of stay and with poorer outcome in terms of early neurological deterioration; hematocrit and Caval Index failed to associate to significant level to prove as a prognostic marker. Initial risk stratification using the plasma osmolality and BUN/Creatinine ratio may assist with prognostication and help prevent deterioration of the patients with Acute Ischemic Stroke.