Hypertensive Urgencies & Emergencies

Key Features

Essentials of Diagnosis

• Hypertensive crisis is typically defined as systolic blood pressure (BP) > 220 mm Hg or diastolic BP > 125 mm Hg

• However, the development of acute end organ damage depends on

  • Rate of rise in BP

  • Magnitude of increase in BP

  • Presence of underlying conditions

General Considerations

• Hypertensive urgency usually has systolic BP > 220 mm Hg or diastolic BP > 125 mm Hg without evidence of acute end-organ damage

• Hypertensive emergency defined as acute hypertensive injury to heart, brain, retina, kidneys, aorta and/or eclampsia

• Encephalopathy or nephropathy accompanying hypertensive retinopathy has historically been termed malignant hypertension, but the therapeutic approach is identical to that used in other hypertensive emergencies

Demographics

• Occurs in any age, gender, or racial/ethnic group

• Usually occurs in people with preexisting hypertension

• Often due to abrupt cessation of antihypertensive therapy

• Also occurs in setting of acute kidney injury or use of high doses of sympathomimetics

Clinical Findings

Symptoms and Signs

• Symptoms depend on the end organ involved

• Headaches, irritability, confusion, and somnolence are signs of encephalopathy

• Chest pain or dyspnea occurs with cardiopulmonary involvement

• Back pain occurs with aortic dissection

• Blurry or diminished vision occurs with retinal involvement

• Cardiac examination may reveal low A2, an S4, or a murmur of aortic regurgitation

• Papilledema is indicative of elevated intracranial pressure

• Crackles on lung examination occur with heart failure

Differential Diagnosis

• Any of the many causes of hypertension can lead to severe hypertension (see Hypertension, Chronic)

• The underlying causes most likely to present in this way include

  • Poorly controlled or undiagnosed hypertension

  • Withdrawal from antihypertensive medications

  • Chronic kidney disease

  • Renal artery stenosis (atherosclerotic or fibromuscular dysplasia)

  • Sympathomimetic drug use

  • Scleroderma crisis

  • Pheochromocytoma

Diagnosis

Laboratory Tests

• Complete blood count (microangiopathic smear with thrombocytopenia due to platelet consumption)

• Urinalysis

• Serum creatinine, blood urea nitrogen, troponin, creatine kinase

• ECG

• Chest radiograph

• Consider urine screen for cocaine

Diagnostic Procedures

• If CNS symptoms, head CT to rule out bleed/infarct

• If chest pain, ECG (to rule out coronary syndrome), chest radiograph (thoracic aortic dissection)

• If kidney dysfunction, renal ultrasound to rule out obstruction or chronic kidney disease

Treatment

Medications

Hypertensive urgency

• Goal is to relieve symptoms and bring BP to reasonable level within 24–48 hours, aiming for gradual attainment of optimal control over several weeks

• Effective oral agents are clonidine, captopril, and slow-release nifedipine

• Avoid beta-blockers if cocaine use

• Avoid angiotensin-converting enzyme (ACE) inhibitors if renal artery stenosis suspected

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