Hypertension is an increasingly prevalent condition as a chronic illness. Frequently it may present in the emergency room as an acute and severe rise in blood pressure, grouped under a classification of hypertensive crisis. This entity is defined as a systolic blood pressure level ¿180 mmHg and/or a diastolic blood pressure level ¿120 mmHg. Clinical manifestations range from no symptoms to signs of severe end-organ damage; therefore in any patient that fulfills these criteria, this diagnosis must be considered. To reach a diagnosis, a complete history, physical examination, basic laboratory tests, and an electrocardiogram are necessary. B-type natriuretic peptide and high-sensitivity cardiac T or I troponin abnormal measurements could stablish a subclinical end-organ damage. We recommend in all patients a careful retina exploration to identify papilledema, hemorrhages, or retinal edema. Treatment should be oriented to tailor goals of clinical context, as some of the causes require a more rapid lowering of blood pressure. A hypertensive emergency should prompt a decrease of the mean arterial pressure by 25% within minutes and up to 2 h with an intravenous agent and should be observed in an inpatient setting, whereas in a hypertensive urgency, outpatient blood pressure control is recommended with oral hypertensives in a maximum of 48 h.
