Remote Ischaemic Conditioning After Stroke Trial (ReCAST-2): A Pilot Randomised Controlled Phase II Trial Evaluating Remote Ischaemic Conditioning (RIC) After Hyperacute Stroke 2

Stroke has an enormous impact on both individual and society. Novel treatments are required to relieve this burden and remote ischaemic conditioning (RIC) is one such approach. RIC refers to applying non-lethal ischaemia to an area distant from an organ you are trying to protect (e.g. the brain). Pre-clinical animal stroke studies have shown RIC to be neuroprotective and help restore functional outcome when compared to control. These outcomes are achieved simply by transiently occluding the blood supply to a limb (e.g. the arm) very soon after the stroke occurs. The mechanisms of protection are unclear but may be due enhancing the body's ability to protect itself from further injury by favorably altering cerebral blood flow or reducing the detrimental effects of oxygen free radicals. Ischaemic conditioning (IC) is an intervention already applied during cardiac surgery to protect the heart from damage and it may be effective after an acute myocardial infarction. The investigators therefore plan to conduct a pilot randomised controlled trial assessing the feasibility of applying RIC (4 cycles of blood pressure cuff inflation for 5 minutes) in patients within 6 hours of ischaemic stroke. The primary outcome is feasibility of RIC. Secondary outcomes include tolerability, safety and clinical efficacy. The results will inform the design of future trials of a potential intervention is that is pragmatic, non-invasive and simple to administer.