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Kempner described the first successful treatment of malignant hypertension with the low-sodium rice diet* Since then multipleeffective therapeutic agents have been discovered. Physicians should be familiar with indications and contraindications, doses and side effects of a few of those agents. Fortunately, modem treatment regimens provide ample means of dealing with diverse conditions. For example, 6-blockers can be used for aortic dissection, or hydralazine or methyl-dopa (in addition to magnesium sulfate) for the hypertensive emergencies of pregnancy. Hypertensive urgencies can be treated with oral nifedipine or clonidine. "Hypertensive emergencies" arise because of malignant acceleration of essential hypertension or because of severe secondary hypertension such as due to pheochromocytoma or the ingestion of tyramine by a patient taking a monoamine oxidase inhibitor (MAOI). Moderate or severe hypertension coexisting with other conditions such as aortic dissection, acute pulmonary edema, eclampsia, or hypertensive encephalopathy requires immediate andhypertensive therapy. Situations that require intervention within hours are often called "hypertensive urgencies," a term popularized by Anderson et al.' Although seemingly arbitrary, the distinction between hypertensive emergencies and urgencies determines the rapidity of intervention and the choice of pharmacologic agents. The physician must decide, based on physical examination and mode of presentation, whether the patient will suffer end-organ damage and vascular necrosis if left untreated. If so, the situation is a hypertensive emergency, and immediate therapeutic intervention is necessary. The choice of agents depends on the cause of the severe hypertension, the presence of coexisting medical conditions, the doctor's "style," and the rapidity with which one wants to lower blood pressure. As a guide to such choices we will focus primarily on drugs (Table 2, at right). Table 3, page 298, suggests treatments for specific diagnostic categories of hypertensive urgencies and emergencies. Pharmacological treatment is almost always indicated for true hypertensive emergencies. Parenteral agents are used to achieve a rapid therapeutic response� essentially a "time-buying" maneuver. Parenteral antihypertensives rarely "cure" severe hypertension (with the notable exception of severe hypertension associated with spinal cord trauma). Therefore, in general, one begins a potent two- or three-drug oral regimen as soon as possible, and titrates the dose upward so that the parenteral agent(s) can be tapered and discontinued. Parenteral Antihypertensive Agents Nitroprusside, a powerful vasodilator, is commonly used to treat hypertensive emergencies.' It can control severe hypertension in almost any setting, and all physicians should be familiar with its properties. Onset of action is almost instantaneous, dose adjustment is easy and rapid, and it produces a consistent hypotensive effect. It does require constant monitoring in an intensive care unit and there is a risk of toxic accumulation of cyanide and thiocyanate. Nitropmsside is indicated for treating high blood pressure associated with encephalopathy, intracranial or subarachnoid bleeding, cerebrovascular accident, heart failure, bums, post-operative hypertension, and head trauma. It can be used for pheochromocytoma and MAOl-tyramine hypertension and, with a B-blocker, for aortic dissection. It should be used with caution in patients with cerebrovascular or cardiovascular disease because a precipitous lowering of blood pressure could cause stroke or cardiac ischemia. Nitroprusside is not advised in pregnant patients. Side effects of nitroprusside include palpitations, tremor, headache, nausea, and vomiting. Thiocyanate, which adversely affects cellular respiration and oxygen transport, may accumulate during prolonged infusion and produce delirium, tinnitus, and diplopia. Thiocyanate levels should be measured when infusions last more dian 24 to 36 hours or if there is renal insufficiency; levels of 10 to 12 mg/dL are toxic and the infusion should be tapered or discontinued. Aggressive coincidentoral anti hypertensive n-eaunent usually allows the infusion to be stopped before thiocyanate toxicity develops. Nitroglycerin, a potent and potentially useful vasodilator, is generally not used intravenously in hypertensive emergencies. Advantages and disadvantages are similar to those of nitroprusside. Nitroglycerin could be an effective and logical agent in cases of left ventricular failure or severe hypertension associated widi cardiac ischemia. In one cross-over study,' nitroglycerin was nearly as effective as nitropmsside in treating severe hypertension after coronary artery bypass surgery. Side effects include headache, ventila-tion-perfusion mismatch, methemoglobinemia, and bradycardia. Diazoxide is a potent arteriolar vasodilator with insignificant effects on capacitance vessels.' It is potent, has a nearly instantaneous onset of action, maximal effect within minutes, and prolonged action (one to 18 hours), which may obviate the need for intensive care unit monitoring or an arterial line. Potential disadvantages include increased cardiac output, refiex tachycardia, and overshoot hypotension. It is indicated in bum cases, severe post-operative hypertension, and hypertensive encephalopadiy. It is con-traindicated in dissecting aneurysm and cardiac ischemia. It must be used with extreme caution in patients with cerebrovascular or cardiovascular disease, stroke, or intracranial or subarachnoid hemorrhage. Diazoxide inhibits pancreatic insulin release, often leading to hyperglycemia. Nausea, vomiting, tachycardia, and hyperuricemia are other potential side effects. Overshoot hypotension can be ameliorated by elevating the legs or infusing 0.9% saline. Giving recommended doses (150 to 300 mg) as a single intravenous bolus has led to stroke and myocardial infarction, particularly in volume-depleted patients. An alternative is to give 30 to 75 mg boluses every five to 30 minutes until the desired effect is achieved or a total of 300 to 600 mg has been given. More doses may be given at four- to eight-hour intervals. Concomitant use of 296 NCMJ /7M/y 1994. Volume 55 Number 7
Object Description
Rating | |
Fixed Title * | NCHH-17: North Carolina Medical Journal [1940-Present] |
Document Title | North Carolina Medical Journal [1940-Present] |
Subject Topical Other | Public Health -- Periodicals.; Physicians -- North Carolina -- Directory.; Societies, Medical -- North Carolina -- Periodicals. |
Description | Includes Transactions of the Society, -1960; 1961- , Transactions issued separately, bound in.; Includes Transactions of the auxiliary to the Medical Society of the State of North Carolina and Proceedings of the North Carolina Public Health Association. Official organ of the Medical Society of the State of North Carolina, 1940-May 1972; of the North Carolina Medical Society, June 1972-. Vols. for 1940-May 1972 published by the Medical Society of the State of North Carolina; June 1972- by the North Carolina Medical Society. |
Contributor | Medical Society of the State of North Carolina. Transactions.; Medical Society of the State of North Carolina.; North Carolina Medical Society.; North Carolina Medical Society. Transactions.; North Carolina Public Health Association. Proceedings. |
Publisher | [Winston-Salem] : North Carolina Medical Society [etc.], 1940- |
Repository | University of North Carolina at Chapel Hill. Health Sciences Library. |
Host | University of North Carolina at Chapel Hill |
Date | 1994 |
Identifier | NCHH-17-055 |
Form General | Periodicals |
Language | English |
Rights | This item is part of the North Carolina History of Health Digital Collection. Some materials in the Collection are protected by U.S. copyright law. This item is presented by the Health Sciences Library of the University of North Carolina at Chapel Hill for research and educational purposes. It may not be republished or distributed without permission of the Health Sciences Library. |
Digital Collection | North Carolina History of Health Digital Collection |
Sponsor | The North Carolina History of Health Digital Collection is an open access publishing initiative of the Health Sciences Library of the University of North Carolina at Chapel Hill. Financial support for the initiative was provided in part by a multi-year NC ECHO (Exploring Cultural Heritage Online) digitization grant, awarded by the State Library of North Carolina, and funded through the Library Services and Technology Act (LSTA). |
Volume Number | 55 |
Health Discipline | Medicine |
Digital Format | JPEG 2000 |
Print / Download PDF Version | http://archives.hsl.unc.edu/nchh/nchh-17/nchh-17-055.pdf |
Document Sort | all; nchh-17 |
Volume Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/identi/searchterm/NCHH-17-055 |
Title Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/documa/searchterm/NCHH-17 |
Catalog Record link | http://search.lib.unc.edu/search?R=UNCb1306322 |
Revision History | done |
Description
Fixed Title * | Page 296 |
Document Title | North Carolina Medical Journal [1940-Present] |
Subject Topical Other | Public Health -- Periodicals.; Physicians -- North Carolina -- Directory.; Societies, Medical -- North Carolina -- Periodicals. |
Description | Includes Transactions of the Society, -1960; 1961- , Transactions issued separately, bound in.; Includes Transactions of the auxiliary to the Medical Society of the State of North Carolina and Proceedings of the North Carolina Public Health Association. Official organ of the Medical Society of the State of North Carolina, 1940-May 1972; of the North Carolina Medical Society, June 1972-. Vols. for 1940-May 1972 published by the Medical Society of the State of North Carolina; June 1972- by the North Carolina Medical Society. |
Contributor | Medical Society of the State of North Carolina. Transactions.; Medical Society of the State of North Carolina.; North Carolina Medical Society.; North Carolina Medical Society. Transactions.; North Carolina Public Health Association. Proceedings. |
Publisher | [Winston-Salem] : North Carolina Medical Society [etc.], 1940- |
Repository | University of North Carolina at Chapel Hill. Health Sciences Library. |
Host | University of North Carolina at Chapel Hill |
Date | 1994 |
Identifier | NCHH-17-055-0104 |
Form General | Periodicals |
Page Type | all; article |
Language | English |
Rights | This item is part of the North Carolina History of Health Digital Collection. Some materials in the Collection are protected by U.S. copyright law. This item is presented by the Health Sciences Library of the University of North Carolina at Chapel Hill for research and educational purposes. It may not be republished or distributed without permission of the Health Sciences Library. |
Filename | ncmed551994junedec_0104.jp2 |
Digital Collection | North Carolina History of Health Digital Collection |
Sponsor | The North Carolina History of Health Digital Collection is an open access publishing initiative of the Health Sciences Library of the University of North Carolina at Chapel Hill. Financial support for the initiative was provided in part by a multi-year NC ECHO (Exploring Cultural Heritage Online) digitization grant, awarded by the State Library of North Carolina, and funded through the Library Services and Technology Act (LSTA). |
Volume Number | 55 |
Issue Number | 7 |
Page Number | 296 |
Health Discipline | Medicine |
Full Text | Kempner described the first successful treatment of malignant hypertension with the low-sodium rice diet* Since then multipleeffective therapeutic agents have been discovered. Physicians should be familiar with indications and contraindications, doses and side effects of a few of those agents. Fortunately, modem treatment regimens provide ample means of dealing with diverse conditions. For example, 6-blockers can be used for aortic dissection, or hydralazine or methyl-dopa (in addition to magnesium sulfate) for the hypertensive emergencies of pregnancy. Hypertensive urgencies can be treated with oral nifedipine or clonidine. "Hypertensive emergencies" arise because of malignant acceleration of essential hypertension or because of severe secondary hypertension such as due to pheochromocytoma or the ingestion of tyramine by a patient taking a monoamine oxidase inhibitor (MAOI). Moderate or severe hypertension coexisting with other conditions such as aortic dissection, acute pulmonary edema, eclampsia, or hypertensive encephalopathy requires immediate andhypertensive therapy. Situations that require intervention within hours are often called "hypertensive urgencies" a term popularized by Anderson et al.' Although seemingly arbitrary, the distinction between hypertensive emergencies and urgencies determines the rapidity of intervention and the choice of pharmacologic agents. The physician must decide, based on physical examination and mode of presentation, whether the patient will suffer end-organ damage and vascular necrosis if left untreated. If so, the situation is a hypertensive emergency, and immediate therapeutic intervention is necessary. The choice of agents depends on the cause of the severe hypertension, the presence of coexisting medical conditions, the doctor's "style" and the rapidity with which one wants to lower blood pressure. As a guide to such choices we will focus primarily on drugs (Table 2, at right). Table 3, page 298, suggests treatments for specific diagnostic categories of hypertensive urgencies and emergencies. Pharmacological treatment is almost always indicated for true hypertensive emergencies. Parenteral agents are used to achieve a rapid therapeutic response� essentially a "time-buying" maneuver. Parenteral antihypertensives rarely "cure" severe hypertension (with the notable exception of severe hypertension associated with spinal cord trauma). Therefore, in general, one begins a potent two- or three-drug oral regimen as soon as possible, and titrates the dose upward so that the parenteral agent(s) can be tapered and discontinued. Parenteral Antihypertensive Agents Nitroprusside, a powerful vasodilator, is commonly used to treat hypertensive emergencies.' It can control severe hypertension in almost any setting, and all physicians should be familiar with its properties. Onset of action is almost instantaneous, dose adjustment is easy and rapid, and it produces a consistent hypotensive effect. It does require constant monitoring in an intensive care unit and there is a risk of toxic accumulation of cyanide and thiocyanate. Nitropmsside is indicated for treating high blood pressure associated with encephalopathy, intracranial or subarachnoid bleeding, cerebrovascular accident, heart failure, bums, post-operative hypertension, and head trauma. It can be used for pheochromocytoma and MAOl-tyramine hypertension and, with a B-blocker, for aortic dissection. It should be used with caution in patients with cerebrovascular or cardiovascular disease because a precipitous lowering of blood pressure could cause stroke or cardiac ischemia. Nitroprusside is not advised in pregnant patients. Side effects of nitroprusside include palpitations, tremor, headache, nausea, and vomiting. Thiocyanate, which adversely affects cellular respiration and oxygen transport, may accumulate during prolonged infusion and produce delirium, tinnitus, and diplopia. Thiocyanate levels should be measured when infusions last more dian 24 to 36 hours or if there is renal insufficiency; levels of 10 to 12 mg/dL are toxic and the infusion should be tapered or discontinued. Aggressive coincidentoral anti hypertensive n-eaunent usually allows the infusion to be stopped before thiocyanate toxicity develops. Nitroglycerin, a potent and potentially useful vasodilator, is generally not used intravenously in hypertensive emergencies. Advantages and disadvantages are similar to those of nitroprusside. Nitroglycerin could be an effective and logical agent in cases of left ventricular failure or severe hypertension associated widi cardiac ischemia. In one cross-over study,' nitroglycerin was nearly as effective as nitropmsside in treating severe hypertension after coronary artery bypass surgery. Side effects include headache, ventila-tion-perfusion mismatch, methemoglobinemia, and bradycardia. Diazoxide is a potent arteriolar vasodilator with insignificant effects on capacitance vessels.' It is potent, has a nearly instantaneous onset of action, maximal effect within minutes, and prolonged action (one to 18 hours), which may obviate the need for intensive care unit monitoring or an arterial line. Potential disadvantages include increased cardiac output, refiex tachycardia, and overshoot hypotension. It is indicated in bum cases, severe post-operative hypertension, and hypertensive encephalopadiy. It is con-traindicated in dissecting aneurysm and cardiac ischemia. It must be used with extreme caution in patients with cerebrovascular or cardiovascular disease, stroke, or intracranial or subarachnoid hemorrhage. Diazoxide inhibits pancreatic insulin release, often leading to hyperglycemia. Nausea, vomiting, tachycardia, and hyperuricemia are other potential side effects. Overshoot hypotension can be ameliorated by elevating the legs or infusing 0.9% saline. Giving recommended doses (150 to 300 mg) as a single intravenous bolus has led to stroke and myocardial infarction, particularly in volume-depleted patients. An alternative is to give 30 to 75 mg boluses every five to 30 minutes until the desired effect is achieved or a total of 300 to 600 mg has been given. More doses may be given at four- to eight-hour intervals. Concomitant use of 296 NCMJ /7M/y 1994. Volume 55 Number 7 |
Digital Format | JPEG 2000 |
Print / Download PDF Version | http://archives.hsl.unc.edu/nchh/nchh-17/nchh-17-055.pdf |
Document Sort | all; nchh-17 |
Article Title | Management Of Hypertensive Emergencies And Urgencies |
Article Author | John R. Raymond; John M. Arthur; Roslyn B. Mannon |
Volume Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/identi/searchterm/NCHH-17-055 |
Title Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/documa/searchterm/NCHH-17 |
Catalog Record link | http://search.lib.unc.edu/search?R=UNCb1306322 |
Revision History | done |
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