What is the difference in treatment approach between hypertensive (HTN) emergency and hypertensive urgency?

Hypertensive Emergency vs. Hypertensive Urgency: Treatment Approach Differences

The primary difference between hypertensive emergency and urgency is that emergencies require immediate blood pressure reduction with parenteral medications in an intensive care setting due to acute end-organ damage, while urgencies can be managed with oral medications over 24-48 hours in an outpatient setting. 1

Definitions and Diagnostic Criteria

Hypertensive Emergency

• Severely elevated BP (>180/120 mmHg) WITH evidence of acute end-organ damage
• Requires hospitalization in ICU
• Requires continuous BP monitoring
• Requires parenteral antihypertensive medications
• Examples of end-organ damage include:
  • Hypertensive encephalopathy
  • Intracerebral hemorrhage
  • Acute myocardial infarction
  • Acute left ventricular failure with pulmonary edema
  • Unstable angina
  • Aortic dissection
  • Eclampsia 1

Hypertensive Urgency

• Severely elevated BP (typically >180/120 mmHg) WITHOUT evidence of acute end-organ damage
• Requires BP reduction within 24-48 hours
• Can usually be managed in outpatient setting
• Treated with oral antihypertensive medications 1

Treatment Goals

Hypertensive Emergency

• Primary goal: Reduce mean arterial pressure by no more than 25% in the first hour
• Secondary goal: Reduce BP to 160/100-110 mmHg within 2-6 hours
• Avoid excessive BP reductions that may precipitate renal, cerebral, or coronary ischemia 1

Hypertensive Urgency

• Gradual BP reduction over 24-48 hours
• Can be achieved with oral medications
• Monitor for several hours to ensure stability before discharge
• Vital sign checks every 30 minutes during first 2 hours
• Schedule follow-up within 24 hours to prevent undetected progression to emergency 1

Medication Management

Hypertensive Emergency

Intravenous medications are recommended:

1. Labetalol: Initial 0.3-1.0 mg/kg (max 20 mg) slow IV injection every 10 min, or 0.4-1.0 mg/kg/h IV infusion up to 3 mg/kg/h (max cumulative dose: 300 mg) 1

2. Nicardipine: Initial dose 5 mg/h, increasing by 2.5 mg/h every 5 min (max dose: 15 mg/h) 1, 2

   • Administered by slow continuous infusion at 0.1 mg/h concentration
   • Blood pressure begins to fall within minutes, reaching 50% of ultimate decrease in about 45 minutes 2

3. Clevidipine: Initial dose 1-2 mg/h, doubling every 90 seconds until BP approaches target (max dose: 32 mg/h, max duration: 72 hours) 1

4. Sodium Nitroprusside: Initial dose 0.3-0.5 mcg/kg/min, increasing in increments of 0.5 mcg/kg/min (max dose: 10 mcg/kg/min)

   • Should be used for shortest duration possible due to cyanide toxicity risk
   • Use should generally be avoided due to toxicity 1, 3

5. Esmolol: Loading dose 500-1000 mcg/kg/min for 1 minute, followed by infusion at 50 mcg/kg/min (max: 200 mcg/kg/min) 1

Hypertensive Urgency

• Oral antihypertensive therapy
• Often combination therapy with a RAS blocker (ACE inhibitor or ARB) plus either a dihydropyridine CCB or diuretic
• Fixed-dose single-pill combinations recommended for better adherence 1

Special Clinical Presentations

Clinical Presentation	First-Line Treatment	Alternative
Most hypertensive emergencies	Labetalol	Nicardipine
Acute coronary event	Nitroglycerin	Labetalol
Acute pulmonary edema	Nitroglycerin + loop diuretic	Labetalol + loop diuretic
Aortic dissection	Esmolol + Nitroprusside (target SBP <120 mmHg within first hour)	Labetalol, Nicardipine
Malignant hypertension with/without acute renal failure	Labetalol	Nicardipine, Nitroprusside
Hypertensive encephalopathy	Labetalol	Nicardipine, Nitroprusside
Acute ischemic stroke (BP >220/120 mmHg)	Labetalol	Nicardipine
Acute hemorrhagic stroke (SBP >180 mmHg)	Labetalol	Nicardipine
Preeclampsia/eclampsia	Hydralazine (target SBP <140 mmHg within first hour)	-

Common Pitfalls and Caveats

1. Avoid immediate-release nifedipine for initial treatment of hypertensive emergencies or urgencies 1

2. Avoid excessive BP reduction that may precipitate renal, cerebral, or coronary ischemia 1

3. Use beta-blockers with caution in patients with suspected catecholamine excess (pheochromocytoma or cocaine toxicity) 1

4. Avoid sodium nitroprusside when possible due to cyanide toxicity risk 3, 4

5. Avoid hydralazine, immediate-release nifedipine, and nitroglycerin as first-line therapies due to significant toxicities and adverse effects 3

6. Monitor closely when titrating medications in patients with congestive heart failure or impaired hepatic or renal function 2

7. Transition planning: When switching from IV to oral therapy, initiate oral therapy upon discontinuation of IV medication. When switching to TID regimen of nicardipine capsules, administer first dose 1 hour prior to discontinuation of infusion 2

8. Follow-up: Ensure monthly follow-up visits until target blood pressure is reached, with particular attention to regression of organ damage 1