Definition of Hypertensive Crisis

Hypertensive crisis refers to a series of clinical manifestations characterized by a sudden, sharp increase in blood pressure, primarily diastolic hypertension, due to transient, intense spasm of the peripheral small arteries induced by certain factors during the course of hypertension. This condition typically occurs in patients with a history of hypertension, but it can also occur in patients not previously diagnosed with hypertension.

Hypertensive crisis includes both hypertensive emergencies and hypertensive urgencies. A hypertensive emergency refers to a sudden elevation in blood pressure, usually with a diastolic pressure exceeding 130 mmHg, accompanied by progressive dysfunction of important target organs such as the heart, brain, and kidneys. When elevated blood pressure does not lead to damage of vital organs, it is termed a hypertensive urgency. Patients with hypertensive crisis may experience symptoms including headache, restlessness, dizziness, nausea, vomiting, palpitations, shortness of breath, and blurred vision.

The key factor in hypertensive crisis is the presence of target organ damage rather than the level of blood pressure itself. The blood pressure reading does not fully reflect the severity of the condition. The extent of target organ damage directly determines the choice of treatment strategy and the patient's prognosis.