Hypertensive Crises.

Despite the availability of effective antihypertensive agents, hypertensive crises still occur with relative frequency and remain an important therapeutic challenge. Hypertensive crises are defined as an abrupt elevation of blood pressure (BP) to a systolic BP reading of more than 210 mm Hg and a diastolic BP level of more than 120 mm Hg. The most important initial clinical decision is to differentiate between hypertensive urgency and hypertensive emergency. In both cases, therapy should be promptly initiated to prevent any permanent loss of organ function or life. The underlying pathophysiology and the intent to avoid adverse effects should guide the choice of antihypertensive agents. The most important principle to remember is to lower the blood pressure sufficiently to limit end-organ dysfunction, but without necessarily reaching normotensive levels. Additionally, it is always important to assess the fluid status of the patient and reestablish euvolemia as soon as feasible to avoid precipitous falls in blood pressure.