Hypertension and Hypertensive Crisis
 Hypertension is a sustained or intermittent elevation in diastolic or systolic blood pressure. It occurs in two major types: essential (primary) hypertension, the most common; and secondary hypertension, which results from renal disease or another identifiable cause. Malignant hypertension is a severe fulmitant form of hypertension common to both types.
Hypertension is a major cause of cerebrovascular accident, cardiac disease, and renal failure. Prognosis is good if this disorder is detected early and treatment begins before complications develop. Severely elevated blood pressure or hypertensive crisis may be fatal.
There is no single identifiable cause of essential hypertension. This condition probably reflects an interaction of multiple homeostatic forces, including changes in renal regulation of sodium and extracellular fluids, in aldosterone secretion and metabolism, and in norepinephrine secretion and metabolism.
Hypertensive crisis, on the other hand, is an acute, life-threatening rise in blood pressure (diastolic usually over 120 mmHg). It may develop in hypertensive patients after abrupt discontinuation of anti-hypertensive medication, increased salt consumption, increased production of rennin, epinephrine, and norepinephrine, and added stress. This emergency requires immediate and vigorous treatment to lower blood pressure and thereby prevent cerebrovascular accident, left heart failure, and pulmonary edema.
Hypertensive crisis produces severe and widespread symptoms, including headache, drowsiness, mental clouding, vomiting, focal neurologic signs (such as paresthesias), and, if pulmonary edema is present, shortness of breath and hemoptysis. Treatment to rapidly lower blood pressure and thereby prevent hypertensive encephalopathy may include vasodilators, such as I.V. nitroprusside, hydralazine, or diaxozide; a potent diuretic, such as furosemide; and a symphathetic blocker, such as methyldopa, trimethaphan, or phentolamine.
In the early stages of antihypertensive I.V. therapy, blood pressure and heart rate should be monitored frequently (as often as one to three minutes with some drugs) for a precipitous drop which indicates hypersensitivity to the prescribed medications. Blood pressure level should be maintained as ordered.
Although hypertension has no cure, drugs and modifications in diet and lifestyle can control it. Drug therapy usually begins with a diuretic alone. Beta- adrenergic blockers, other sympathetic blockers, or vasodilators may be added as needed. Therapy may also include angiotensin-converting enzyme and calcium channel blockers. Lifestyle and dietary changes may include weight loss, relaxation techniques, regular exercise, and restriction of sodium and saturated fat intake.
To encourage compliance with antihypertensive therapy, it should be suggested that the patient establish a daily routine for taking medication. Patient should be warned that uncontrolled hypertension may cause stroke and heart attack. Patient should also be taught to report drug side effects.
 December 23, 2009
 Tags: hypertension causes, hypertension emedicine, hypertension heart, hypertension symptoms, severe hypertension Posted in: Hypertension
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