Christopher J. Hebert, MD*, Donald G. Vidt, MD
Department of Nephrology and Hypertension, Cleveland Clinic, Suite A51, 9500 Euclid Avenue, Cleveland, OH 44195, USA
Hypertension is the most common reason for a physician oﬃce visit in the United States . The primary care physician should therefore expect to see theoccasional patient with very elevated blood pressure, deﬁned as greater than 180/110 mm Hg. Expedited triage of such patients is necessary to identify the minority of patients that would beneﬁt from acute reduction in blood pressure. Hypertensive crises are those situations in which markedly elevated blood pressure is accompanied by progressive or impending acute target organ damage. The discussion thatfollows addresses the assessment, treatment, and follow-up care for patients with very elevated blood pressure, with an emphasis on hypertensive crises. Deﬁnitions Patients presenting with very high blood pressuredblood pressure greater than 180/110 mm Hgdshould be triaged into one of three mutually exclusive groups. 1. Severe hypertension is present when blood pressure exceeds 180/110 mm Hg inthe absence of symptoms beyond mild or moderate headache, and without evidence of acute target organ damage. 2. Hypertensive urgency is present when blood pressure exceeds 180/ 110 mm Hg in the presence of signiﬁcant symptoms, such as severe headache or dyspnea, but no or only minimal acute target organ damage. 3. Hypertensive emergency is present when very high blood pressure (often O220/140 mm Hg)is accompanied by evidence of life-threatening organ dysfunction. Box 1 lists the important causes of hypertensive emergencies.
* Corresponding author. E-mail address: firstname.lastname@example.org (C.J. Hebert). 0095-4543/08/$ - see front matter Ó 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.pop.2008.05.001 primarycare.theclinics.com
HEBERT & VIDT
Box 1. Examples of hypertensiveemergencies Acute ischemic or hemorrhagic stroke Subarachnoid hemorrhage Hypertensive encephalopathy Acute myocardial ischemia/infarction Acute heart failure Acute aortic dissection Eclampsia Head trauma Catecholamine excess states Beta-blocker or clonidine withdrawal Cocaine, phencyclidine hydrochloride use Pheochromocytoma crisis Hemorrhage Postsurgical Severe epistaxis
The term hypertensivecrisis is used to indicate either a hypertensive urgency or emergency. There are two older terms that are notable. Malignant hypertension represents markedly elevated blood pressure accompanied by papilledema (grade 4 retinopathy). Accelerated hypertension is considered present if markedly elevated blood pressure is accompanied by grade 3 retinopathy, but no papilledema. However, the three numberedterms above usually suﬃce for the description of all clinical scenarios involving very high blood pressure. Epidemiology Among the 65 million Americans with hypertension, the minority have controlled blood pressure, with estimates falling between 38% and 44% [1,2]. Hypertensive crises, however, occur in less than 1% of individuals with hypertension . Although crises are infrequent, very elevatedblood pressure is a common clinical scenario facing the physician. In the United States, more that 250,000 emergency department visits in 2005 were attributed to the diagnosis of hypertension (International Classiﬁcation of Diseases, Ninth Revision [ICD9] diagnoses 401.0, 401.1, 401.9), with 14% resulting in hospital admission . Some have suggested that hospitalization for hypertensiveemergency reﬂects upon the quality of ambulatory care (ie, an ambulatory care– sensitive condition) . There are two ways in which an emergency department evaluation might indicate poor-quality ambulatory care. First, the treating physician may have failed to achieve good blood pressure control,
resulting in less eﬀective care . Secondly, a patient with very...