What is the definition and management of hypertensive urgency and emergency in patients with a history of hypertension, cardiovascular disease, or kidney disease?

Hypertensive Emergency and Urgency: Definitions

Core Definitions

Hypertensive emergency is defined as severely elevated blood pressure (>180/120 mmHg) WITH evidence of new or progressive acute target organ damage, requiring immediate ICU admission and IV antihypertensive therapy. 1, 2 In contrast, hypertensive urgency is severely elevated blood pressure (>180/120 mmHg) WITHOUT acute target organ damage, manageable with oral medications and outpatient follow-up. 1, 2

The presence or absence of acute target organ damage—not the absolute blood pressure number—is the sole distinguishing factor between these two conditions. 1, 2 The rate of blood pressure rise may be more important than the absolute value, as patients with chronic hypertension often tolerate higher pressures than previously normotensive individuals. 1

Target Organ Damage Manifestations

Acute target organ damage defining a hypertensive emergency includes: 1, 2

Neurologic Damage

• Hypertensive encephalopathy (altered mental status, headache, visual disturbances, seizures) 1, 3
• Intracranial hemorrhage 1
• Acute ischemic stroke 1

Cardiac Damage

• Acute myocardial infarction 1, 2
• Unstable angina 1
• Acute left ventricular failure with pulmonary edema 1, 2

Vascular Damage

• Aortic dissection or aneurysm 1

Renal Damage

• Acute kidney injury 1
• Hypertensive thrombotic microangiopathy 1

Ophthalmologic Damage

• Malignant hypertension with bilateral retinal hemorrhages, cotton wool spots, or papilledema (Grade III-IV retinopathy) 1

Obstetric Complications

• Severe preeclampsia or eclampsia 1

Clinical Significance and Prognosis

Without treatment, hypertensive emergencies carry a 1-year mortality rate >79% and median survival of only 10.4 months. 1 However, with prompt recognition and appropriate treatment, conditions like hypertensive encephalopathy are fully reversible. 3

Management Implications

Hypertensive Emergency Management 1, 2

• Immediate ICU admission (Class I recommendation, Level B-NR)
• Continuous arterial blood pressure monitoring
• Parenteral (IV) titratable short-acting antihypertensive agents
• Target: Reduce mean arterial pressure by 20-25% (or systolic blood pressure by no more than 25%) within the first hour
• Then reduce to 160/100 mmHg over 2-6 hours if stable
• Cautiously normalize over 24-48 hours

Hypertensive Urgency Management 1, 2

• Oral antihypertensive therapy initiation or adjustment
• Outpatient follow-up within 2-4 weeks
• Gradual blood pressure reduction over 24-48 hours
• No hospital admission or IV medications required

Critical Diagnostic Pitfalls to Avoid

Do not treat the blood pressure number alone without systematically assessing for true target organ damage. 1, 2 Up to one-third of patients with diastolic blood pressure >95 mmHg normalize before arranged follow-up, and rapid blood pressure lowering in asymptomatic patients may be harmful. 1

Avoid excessive acute blood pressure drops (>70 mmHg systolic), which can precipitate cerebral, renal, or coronary ischemia, particularly in patients with chronic hypertension who have altered autoregulation. 1, 2

Never use immediate-release nifedipine due to unpredictable precipitous blood pressure drops and reflex tachycardia. 1, 2

Special Considerations

Secondary causes are found in 20-40% of patients with malignant hypertension, necessitating screening for conditions such as renal artery stenosis, pheochromocytoma, or primary aldosteronism after stabilization. 1 Medication non-adherence is the most common trigger for hypertensive emergencies. 1