Hypertensive crisis is a category of hypertensive emergencies with very high mortality and disability rates. Hypertensive crisis includes the following two aspects: 1, acute development of chronic hypertension: diastolic blood pressure continues to exceed 140 mmHg, when patients may develop fundus symptoms, such as optic papilloedema, fundus hemorrhage or exudation, in addition to the symptoms of intracranial hypertension, manifested as nausea, vomiting, transient cerebral ischemia, requiring emergency treatment; 2, hypertensive encephalopathy: the patient’s average blood pressure continues to exceed 180 mmHg, which will exceed the brain’s own regulatory capacity, leading to cerebral edema and some manifestations of intracranial hypertension, such as headache, nausea, vomiting, cerebral hemorrhage and the occurrence of blurred vision, hemiparesis and blindness. Hypertensive crisis either hypertensive encephalopathy or diastolic blood pressure persistently exceeding 140mmHg can lead to emergencies in patients, such as cerebral hemorrhage, cerebral infarction or continuous increase in blood pressure, tearing the aorta to develop aortic coarctation or bleeding from the fundus of the eye leading to blindness, etc. It is a very dangerous disease and a more serious consequence of hypertension.