hypertensive%20crisis
HYPERTENSIVE CRISIS
Hypertensive emergency is having severely elevated blood pressure (>180-220 mmHg/120-130 mmHg) that is complicated by progressive target end-organ damage of the central nervous system, heart, kidneys, or the gravid uterus.
There is no definite blood pressure threshold for the diagnosis of hypertensive emergency.
Most target end-organ damage happen with diastolic blood pressure of ≥130 mmHg.
Hypertensive urgency refers to patients with severely elevated blood pressure (>180/110-120 mmHg) but with little or no evidence of acute end-organ damage.
The clinical differentiation between hypertensive emergencies and urgencies is dependent on the presence of target end-organ damage rather than the level of blood pressure.

Principles of Therapy

  • Primary objective is to reverse or reduce target organ damage
  • Assessment of the volume status of the patient is important prior to intravenous therapy (IV) therapy

Treatment Goal

Depending on the clinical situation:

  • Correct the blood pressure (BP) to no less than 20-25% in the first hour, then if stable to 160/100-110 mmHg within the next 2-6 hours
    • Avoid excessive reduction in pressure that may result in coronary, cerebral or renal ischemia; exceptions include patients with aortic dissection, ischemic stroke, or those who will use thrombolytic agents 
  • Alternative is reduction of diastolic blood pressure (DBP) by 10-15% or to approximately 110 mmHg in 30-60 minutes, with a goal to reduce to normal BP within 24-48 hours

Pharmacotherapy

Hypertensive Emergency

  • No evidence exists to recommend one agent over another in reducing morbidity or mortality
  • Drug of choice is based on individual presentation, comorbidities, contraindications, and the presence and type of end-organ damage

Acute Aortic Dissection

  • Preferred treatments: Labetalol, Esmolol, Nitroprusside (with beta-blocker), Nicardipine
  • Intravenous (IV) antihypertensive treatment should be started as soon as acute aortic dissection is suspected
  • Avoid beta-blockers in the presence of aortic valvular regurgitation or suspected cardiac tamponade
  • Systolic blood pressure (SBP) should be reduced to <120 mmHg and a mean arterial pressure (MAP) of <80 mmHg within 5-10 minutes

Acute Coronary Syndrome

  • Preferred treatments: Esmolol with GTN, Labetalol with GTN, Nitroprusside
    • Nitrates lower left ventricle (LV) preload and cardiac output and improve coronary blood flow
    • Beta-blockers reduce heart rate, decrease afterload and improve diastolic coronary perfusion
  • Give treatment if SBP >160 mmHg and/or diastolic blood pressure (DBP) >100 mmHg
  • Thrombolytics should not be given if blood pressure (BP) is >185/100 mmHg

Acute Heart Failure

  • Preferred treatments: GTN, Enalapril, Clevidipine
    • Enalapril can reduce afterload thus improving cardiac output
    • Clevidipine decreases peripheral vascular resistance; was shown in a small study to be effective in reducing BP without adverse reactions
  •  Use vasodilators + diuretics for SBP ≥140 mmHg; GTN, given IV or sublingually, is preferred

Acute Renal Failure/Microangiopathic Anemia

  • Preferred treatments: Fenoldopam, Nicardipine
    • Fenoldopam is a selective dopamine-1 receptor agonist that increases renal perfusion
  •  In acute renal insufficiency, MAP should be reduced by 20-25%

Acute Intracerebral Hemorrhage

  • Preferred treatments: Labetalol, Nicardipine, Fenoldopam, Esmolol
  • In the presence of increased intracranial pressure (ICP), maintain MAP <130 mmHg or SBP <180 mmHg for the 1st 24 hours after onset; avoid reductions in BP to <110 mmHg 
  • In the absence of increased ICP, maintain MAP <110 mmHg or SBP <160 mmHg for the 1st 24 hours after onset

Acute Ischemic Stroke

  • Preferred treatments: Labetalol, Nicardipine, Fenoldopam, Clevidipine
  • Do not give antihypertensive agents unless SBP >220 mmHg or DBP >120 mmHg
    • If DBP is >140 mmHg, Nitroprusside may be given to obtain a 10-15% reduction in 24 hours
  • MAP should be reduced by maximum of 15-20% or to DBP not less than 100-110 mmHg within the first 24 hours; however, if patient is receiving fibrinolytic therapy, the goal BP is <185/110 mmHg

Hypertensive Encephalopathy

  • Preferred treatments: Labetalol, Nicardipine, Fenoldopam, Clevidipine
  • MAP should be reduced by maximum of 20% or to DBP 100-110 mmHg within the first hour then gradual reduction in BP in normal range over 48-72 hours

Subarachnoid Hemorrhage

  • Preferred treatments: Labetalol, Nicardipine or Esmolol
  • SBP should be maintained <160 mmHg until aneurysm is treated or cerebral vasospasm occurs

Adrenergic Crisis

  • Hyperadrenergic states include sympathomimetic drug use (eg cocaine, amphetamines, phenylpropanolamine, combination of MAOIs with tyramine-rich foods), pheochromocytoma or after sudden discontinuation of a short-acting sympathetic blocker 
  • Preferred treatments for pheochromocytoma: Phentolamine, Labetalol with Nitroprusside
  • Preferred treatments for sympathetic crisis related to use of sympathomimetic drugs: Benzodiazepines, Phentolamine, Labetalol with Nitroprusside, Verapamil, Diltiazem, Nicardipine in combination with Benzodiazepine
  • Alpha-blockers are preferred agents
    • Avoid selective beta-blockers which can worsen hypertension

Severe Pre-eclampsia or Eclampsia

  • Preferred treatments: Labetalol, Hydralazine, Nicardipine
  • Avoid Nitroprusside, ACE inhibitors, ARBs and Esmolol
  • SBP should be kept from 140-160 mmHg and DBP from 90-105 mmHg
    • SBP >160mmHg has been associated with cerebrovascular accidents
  •  Magnesium sulfate should be given to prevent seizures

Acute Postoperative Hypertension

  • Preferred treatments: Labetalol, Nicardipine, Clevidipine, Esmolol, Urapidil
  • Treatment is indicated in cardiac surgery patients with a BP>140/90 or a MAP of at least 105 mmHg

Hypertensive Urgency

The term “hypertensive urgency” has led to overly aggressive management of many patients

  • Reduce BP to 160/100 mmHg over hours to days
  • Reduction of BP in these patients may be achieved with short-acting oral medications and without intensive monitoring
  • No consensus exists stating that initiating treatment in the ED is cost-effective and improves long-term patient care
  • Please see Hypertension Disease Management Chart for full dosage guidelines of the following oral agents

Captopril

  • Considered first-line agent
  • Onset of action is within 30-60 minutes
  • Co-administration of a loop diuretic enhances the effect of this drug
  • Avoid in patients with high-grade bilateral renal artery stenosis
  • Please see Hypertension Disease Management Chart for dosage guidelines of diuretics.

Clonidine

  • Onset of action is within 30-60 minutes
  • Avoid in patients requiring mental status monitoring

Labetalol

  • Onset of action is within 20-120 minutes
  • Avoid in patients with asthma as this may worsen bronchospasm
  • Use with caution in patients with symptomatic bradycardia, congestive heart failure (CHF) and heart block

Nifedipine (extended-release)

  • Onset of action is within 20 minutes
  • Avoid the use of short-acting oral or sublingual Nifedipine due to risk of stroke, acute myocardial infarction (MI) and severe hypotension

Amlodipine

  • Onset of action is within 30-50 minutes

Prazosin

  • Onset of action is within 2-4 hours
  • May cause postural hypotension and syncope with 1st dose
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