Management of Hypertensive Crises

SUMMARY Malignant hypertension still constitutes a medical emergency, particularly when com-plicated by renal failure, encephalopathy, or left ventricular failure. A shift to the right of the autoregulatory curve of cerebral blood flow (and probably of renal blood flow) is known to occur in patients with hypertension. Local cerebral edema, complicating the malignant phase, is likely to aggravate this trend. While inadequate or tardy treatment leads to encephalopathy, renal and cardiac failure, overaggressive treatment may also result in damage to brain, heart, and kidney. Recent reports of neurological damage, sometimes fatal, following aggressive hypotensive treatment suggests the need for a reappraisal of current practices. More investigation is needed to determine the effects of the various classes of antihypertensive drugs on organ perfusion, particularly of brain, heart, and kidney, in both normal and hypertensive humans. Other hypertensive crises include raised arterial pressure in association with acute dissection of the aorta and in the presence of stroke or subarachnoid hemorrhage. While there is agreement about the need for urgent hypotensive treatment in patients with aortic dissection, there is no information with which to base rational decisions in the manage-ment of high arterial pressure in the acute phase of stroke or subarachnoid hemorrhage. (Hypertension 5 (supp III): III-114-III-119, 1983) KEY WORDS • accelerated hypertension • hypertensive encephalopathy • stroke • subarachnoid hemorrhage • dissecting aneurysm SITUATIONS in which the need to lower arterialpressure acutely constitute an emergency.These situations are few; chief among them are hypertension in the malignant phase (complicated or not by encephalopathy, renal failure, or left ventricular failure) and hypertension associated with acute dis-secting aneurysm of the aorta. Malignant hypertension is now much less common1'2 than it was when Kincaid-Smith and her colleagues3 estimated it to occur in as many as 1 % of the hypertensive population, perhaps because of improved methods of detection and treat-ment of patients with high arterial pressure. Particular difficulties in the treatment of hypertension arise also in the management of patients who have suffered a stroke or subarachnoid hemorrhage