Hypertensive Crisis

Chapter 52


Hypertensive Crisis





1. What is a hypertensive crisis?


    The term hypertensive crisis generally is inclusive of two different diagnoses, hypertensive emergency and hypertensive urgency. Distinguishing between the two is important because they require different intensities of therapy. It should be noted that older and less specific terminology, such as “malignant hypertension” and “accelerated hypertension,” should no longer be used. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-7) defines hypertensive emergency as being “characterized by severe elevations in blood pressure (more than 180/120 mm Hg), complicated by evidence of impending or progressive target organ dysfunction.” JNC-7 defines hypertensive urgency as “those situations associated with severe elevations in blood pressure without progressive target organ dysfunction.” There is no absolute value of blood pressure that defines a hypertensive urgency or emergency or separates the two syndromes. Instead, the most important distinction is whether there is evidence of impending or progressive end-organ damage, which defines an emergency, or other symptoms that are felt referable to the blood pressure.


2. How commonly do these situations occur?


    It is estimated that 50 to 75 million people have hypertension and that 1% to 2% of those will have a hypertensive emergency. In the elderly (>65 years of age), essential hypertension accounts for 424,000 emergency department (ED) visits per year, with an estimated 0.5% of all ED visits attributed to hypertensive crises.


3. What are the causes of hypertensive crisis?


    The most common cause of hypertensive emergency is an abrupt increase in blood pressure in patients with chronic hypertension. Medication noncompliance is a frequent cause of such changes. Blood pressure control rates for patients diagnosed with hypertension are less than 50%. The elderly and African Americans are at increased risk of developing a hypertensive emergency. Other causes of hypertensive emergencies include stimulant intoxication (cocaine, methamphetamine, and phencyclidine), withdrawal syndromes (clonidine, β-adrenergic blockers), pheochromocytoma, physiologic stress in the postoperative period (following cardiothoracic, vascular, or neurosurgical procedures), and adverse drug interactions with monoamine oxidase (MAO) inhibitors.


4. What are the common clinical presentations of hypertensive crisis?


    Typical presentations include severe headache, shortness of breath, epistaxis, faintness, or severe anxiety. Clinical syndromes typically associated with hypertensive emergency include hypertensive encephalopathy, intracerebral hemorrhage, acute myocardial infarction, acute heart failure, pulmonary edema, unstable angina, dissecting aortic aneurysm, or preeclampsia/eclampsia. Note that in hypertensive emergency presentations, there is evidence of impending or progressive target organ dysfunction and that the absolute value of the blood pressure is not pathognomonic.


5. What historical information should be obtained?


    A thorough history, especially as it relates to prior hypertension, is important to obtain and document, as most patients with a hypertensive emergency carry a diagnosis of hypertension and are either inadequately treated or are noncompliant with treatment.


    A thorough medication history is also essential. The patient’s current medications need to be reviewed and updated to include timing, dosages, recent changes in therapy, last doses taken, and compliance. Patients should also be questioned about over-the-counter medication usage and recreational drug use because these agents may also affect blood pressure.


6. How should the physical examination be focused?


    Physical examination should start with recording the blood pressure in both arms with an appropriately sized blood pressure cuff. Direct ophthalmoscopy should be performed with attention to evaluating for papilledema and hypertensive exudates. A brief, focused neurologic examination to assess mental status and the presence or absence of focal neurologic deficits should be performed. The cardiopulmonary examination should focus on signs of pulmonary edema and aortic dissection, such as rales, elevated jugular venous pressure, or cardiac gallops. Peripheral pulses should be palpated and assessed. Abdominal examination should include palpation for abdominal masses and tenderness, and auscultation for abdominal bruits.


7. What laboratory and ancillary data should be obtained?

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Jun 5, 2016 | Posted by in CARDIOLOGY | Comments Off on Hypertensive Crisis

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