Hypertensive Crises

Hypertensive crises are a group of medical conditions in which a rapid decrease in blood pressure is necessary to prevent serious complications. Although uncommon in clinical practice, a hypertensive crisis should be recog nized and treated promptly. Any form of hypertension may be associated with hypertensive crisis, the main determinant being the level of blood pressure rather than the cause of hypertension. In certain clinical situa tions the abruptness with which the blood pressure in creases seems to be more important than the absolute level of blood pressure in causing the hypertensive crisis (e.g., toxemia of pregnancy in women and acute onset of hypertension in children with acute glomerulo nephritis). In other clinical situations the absolute level of blood pressure does not affect the seriousness of hy pertension so much as coexisting complications that may make even moderate hypertension dangerous (e.g., acute aortic dissection and acute left ventricular fail ure ).