What is the management approach for an adult patient with a history of hypertension and severely elevated blood pressure, differentiating between a hypertensive emergency and urgency?

Hypertensive Emergency vs Urgency: Critical Differentiation and Management

Defining the Critical Distinction

The presence of acute target organ damage—not the absolute blood pressure number—is the sole factor that distinguishes a hypertensive emergency from urgency. 1

Hypertensive Emergency

• Blood pressure >180/120 mmHg WITH evidence of new or worsening target organ damage requiring immediate ICU admission and IV therapy 1
• Without treatment, carries a 1-year mortality rate >79% and median survival of only 10.4 months 1
• The rate of BP rise may be more important than the absolute value; patients with chronic hypertension often tolerate higher pressures than previously normotensive individuals 1

Hypertensive Urgency

• Severely elevated blood pressure WITHOUT acute organ damage, managed with oral medications and outpatient follow-up 2
• Does not require hospitalization or IV medications 2
• Up to one-third of patients with diastolic BP >95 mmHg normalize before arranged follow-up 2

Target Organ Damage Assessment Algorithm

Immediately assess for these specific manifestations:

Neurologic Damage

• Hypertensive encephalopathy: altered mental status, headache with vomiting, visual disturbances, seizures 1
• Intracranial hemorrhage 1
• Acute ischemic stroke 1

Cardiac Damage

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

Vascular Damage

• Aortic dissection or aneurysm 1

Renal Damage

• Acute kidney injury with elevated creatinine 1
• Thrombotic microangiopathy (thrombocytopenia, elevated LDH, decreased haptoglobin) 1
• Proteinuria and abnormal urine sediment 1

Ophthalmologic Damage

• Bilateral retinal hemorrhages, cotton wool spots, or papilledema (malignant hypertension) 1
• Note: Isolated subconjunctival hemorrhage is NOT acute target organ damage 1

Management Algorithm

If Target Organ Damage Present (Hypertensive Emergency)

Immediate Actions:

• ICU admission with continuous arterial line BP monitoring (Class I recommendation) 1
• Initiate parenteral (IV) antihypertensive therapy immediately 1

Blood Pressure Targets:

• Reduce mean arterial pressure by 20-25% within the first hour 1
• Then if stable, reduce to 160/100 mmHg over 2-6 hours 1
• Cautiously normalize over 24-48 hours 1
• Exception for aortic dissection: reduce SBP to <120 mmHg within 20 minutes 1
• Avoid excessive drops >70 mmHg systolic, which can precipitate cerebral, renal, or coronary ischemia 1

First-Line IV Medications by Clinical Scenario:

• Hypertensive encephalopathy: Nicardipine 5 mg/hr IV, titrate by 2.5 mg/hr every 15 minutes (max 15 mg/hr) OR labetalol 10-20 mg IV bolus over 1-2 minutes 1, 3

• Acute coronary syndrome/pulmonary edema: Nitroglycerin 5-10 mcg/min IV, titrate by 5-10 mcg/min every 5-10 minutes, target SBP <140 mmHg immediately 1

• Aortic dissection: Esmolol plus nitroprusside/nitroglycerin, target SBP ≤120 mmHg within 20 minutes (beta blockade must precede vasodilator to prevent reflex tachycardia) 1

• Eclampsia/preeclampsia: Hydralazine, labetalol, or nicardipine (ACE inhibitors, ARBs, and nitroprusside are absolutely contraindicated) 1

• Acute ischemic stroke: Avoid BP reduction unless BP >220/120 mmHg; if eligible for reperfusion therapy, maintain BP <180/105 mmHg for first 24 hours 1

• Intracerebral hemorrhage: Carefully lower SBP to 140-160 mmHg within 6 hours if presenting SBP ≥220 mmHg 1

Medications to Avoid:

• Immediate-release nifedipine (unpredictable precipitous drops and reflex tachycardia) 1
• Sodium nitroprusside except as last resort (cyanide toxicity risk with prolonged use >48-72 hours) 1
• Hydralazine as first-line (unpredictable response and prolonged duration) 1

If NO Target Organ Damage (Hypertensive Urgency)

Management Approach:

• Initiating treatment for asymptomatic hypertension in the ED is not necessary when patients have follow-up (Level B recommendation) 2
• Rapidly lowering blood pressure in asymptomatic patients in the ED is unnecessary and may be harmful (Level B recommendation) 2
• Initiate or adjust oral antihypertensive therapy 2
• Arrange outpatient follow-up within 2-4 weeks 1
• Target BP <130/80 mmHg (or <140/90 mmHg in elderly/frail) achieved over 3 months 1

Oral Medication Selection:

• Non-Black patients: Start low-dose ACE inhibitor or ARB, add dihydropyridine calcium channel blocker if needed, add thiazide/thiazide-like diuretic as third-line 1
• Black patients: Start low-dose ARB plus dihydropyridine calcium channel blocker OR calcium channel blocker plus thiazide/thiazide-like diuretic 1

Essential Laboratory Evaluation for Hypertensive Emergency

Obtain immediately:

• Complete blood count (hemoglobin, platelets) to assess for microangiopathic hemolytic anemia 1
• Basic metabolic panel (creatinine, sodium, potassium) to evaluate renal function 1
• Lactate dehydrogenase and haptoglobin to detect hemolysis in thrombotic microangiopathy 1
• Urinalysis for protein and urine sediment examination 1
• Troponins if chest pain present 1
• ECG to assess for cardiac involvement 1

Critical Pitfalls to Avoid

• Do not treat the BP number alone without assessing for true target organ damage—many patients with acute pain or distress have transiently elevated BP that normalizes when the underlying condition is treated 1
• Do not rapidly lower BP in hypertensive urgency—this may cause harm through hypotension-related complications including acute kidney injury, cerebral ischemia, or coronary ischemia 2, 1
• Do not use IV medications for hypertensive urgency—oral therapy is appropriate 1
• Do not lower BP to "normal" acutely in hypertensive emergency—patients with chronic hypertension have altered autoregulation and cannot tolerate acute normalization 1
• Do not use beta-blockers alone in cocaine or amphetamine intoxication—use benzodiazepines first, then phentolamine, nicardipine, or nitroprusside if additional BP control needed 1
• Do not delay screening for secondary hypertension after stabilization—20-40% of malignant hypertension cases have secondary causes including renal artery stenosis, pheochromocytoma, or primary aldosteronism 1