Remote ischemic conditioning (RIC) is a promising safe, feasible, and inexpensive treatment for acute stroke, both ischemic and hemorrhagic. It is applied with a blood pressure cuff on the limbs and is ideal for the prehospital setting. RIC is a form of preconditioning with similarities to physical exercise. Its mechanisms of action are multiple and include improvement of collateral cerebral blood flow (CBF) and RIC acts as a "collateral therapeutic". The increased CBF is likely related to nitric oxide synthase 3 in the endothelium and more importantly in circulating blood cells like the red blood cell. The RESIST clinical trial is a 1500 subject multicenter, randomized, sham-controlled trial of RIC in the prehospital setting in Denmark and should address the questions of whether RIC is safe and effective in acute stroke and whether the effect is mediated by an effect on nitric oxide/nitrite metabolism.
Keywords: nitric oxide synthase 3; preconditioning; red blood cell; remote ischemic conditioning.