Ischemic stroke occurs when an artery that supplies blood to the brain is blocked by a blood clot or fatty buildup, called plaque. This blockage can appear at the neck or in the skull. ... Plaque can also build up in the arteries that supply blood to the brain and narrow those arteries enough to cause ischemic stroke. An IV injection of recombinant tissue plasminogen activator (tPA) — also called alteplase (Activase) — is the gold standard treatment for ischemic stroke. An injection of tPA is usually given through a vein in the arm with the first three hours. Sometimes, tPA can be given up to 4.5 hours after stroke symptoms started. The main treatment for ischemic stroke is intravenous tissue plasminogen activator (tPA), which breaks up clots. 2018 guidelines from the American Heart Association (AHA) and the American Stroke Association (ASA) state that tPA is most effective when it's given within four and a half hours from the start of a stroke. The first three days after a patient is admitted to a stroke care facility is called the hyper acute care, and it covers a time period from the moment the patient enters the hospital to the time he/she is out of imminent danger. ... This allows the doctor to decide if the patient needs surgery or thrombolysis