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 objectives are to reverse or reduce target organ damage and to begin appropriate antihypertensive therapy
  • 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 SBP to no more than 25% in the first hour, then if stable to 160/100 mmHg within the next 2-6 hours, then to normal in the next 24-48 hours
    • Avoid excessive reduction in pressure that may result in coronary, cerebral or renal ischemia; exceptions include patients with aortic dissection, pheochromocytoma crisis, 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, the presence and type of end-organ damage, the drug’s pharmacology, and the desired rate of BP reduction 

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
  • Reduce SBP to <140 mmHg within the 1st hour and to <120 mmHg in patients with aortic dissection

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 Pulmonary Edema  

  • Preferred treatments: Clevidipine, GTN, Nitroprusside
  • Avoid using beta-blockers

Acute Renal Failure/Microangiopathic Anemia

  • Preferred treatments: Fenoldopam, Nicardipine, Clevidipine
    • 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, renin inhibitors, and Esmolol
  • SBP should be reduced to <140 mmHg within the 1st hour of therapy
    • SBP >160 mmHg 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
Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Cardiology - Malaysia digital copy today!
DOWNLOAD
Editor's Recommendations
Most Read Articles
19 Dec 2016
The prevalence of ECG for left ventricular hypertrophy (LVH) may vary depending on the criteria used across body mass index (BMI) categories in a low cardiovascular risk cohort, suggests a new study.
02 Dec 2017
The risk of congenital heart disease (CHD) Is significantly higher in foetuses conceived through in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI), according to a recent study.
Pearl Toh, 3 days ago
A higher dose of pitavastatin can benefit Japanese patients with stable coronary artery disease (CAD) compared with a low-dose pitavastatin, even though cardiovascular (CV) event incidence is known to be lower in Asian than Western patients, according to the REAL-CAD study presented at the AHA Scientific Sessions 2017.
01 Apr 2014
The basic life support (BLS) termination of resuscitation (TOR) rule recommends transport and continued resuscitation when cardiac arrest is witnessed by EMT-Ds, or there is a return of spontaneous circulation, or a shock is given.