Overview

Definitions and classification

• Severe hypertension (hypertensive crisis): 
  • A confirmed blood pressure ≥ 180 mm Hg systolic and/or ≥ 120 mm Hg diastolic
  • May occur in previously undiagnosed or known hypertensive individuals
  • May be isolated or sustained
  • A clinical spectrum:
    • Hypertensive urgency: asymptomatic, or relative asymptomatic, severe hypertension without end-organ damage
    • Hypertensive emergency: severe hypertension associated with signs of end-organ damage
• Resistant hypertension: Blood pressure that remains uncontrolled despite concurrent use of 3 antihypertensive agents of different classes:
  • Of these agents, 1 must be a diuretic (or a diuretic was not tolerated).
  • All must be dosed at the maximum allowable (or tolerable) dose.
  • Blood pressureP that is controlled on maximal doses of ≥ 4 medications belong to this class by default.
• Refractory hypertension:
  • Blood pressure that cannot be controlled even with maximally tolerated doses of ≥ 5 drugs
  • Must include chlorthalidone
  • Must include spironolactone
• Secondary hypertension:
  • Resistant hypertension with an identifiable and potentially treatable etiology
  • Renal artery stenosis Renal artery stenosis Renal artery stenosis (RAS) is the narrowing of one or both renal arteries, usually caused by atherosclerotic disease or by fibromuscular dysplasia. If the stenosis is severe enough, the stenosis causes decreased renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS) and leads to renovascular hypertension (RVH). Renal Artery Stenosis ( RAS RAS Renal artery stenosis (RAS) is the narrowing of one or both renal arteries, usually caused by atherosclerotic disease or by fibromuscular dysplasia. If the stenosis is severe enough, the stenosis causes decreased renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS) and leads to renovascular hypertension (RVH). Renal Artery Stenosis)
  • Primary hyperaldosteronism Hyperaldosteronism Hyperaldosteronism is defined as the increased secretion of aldosterone from the zona glomerulosa of the adrenal cortex. Hyperaldosteronism may be primary (resulting from autonomous secretion), or secondary (resulting from physiological secretion due to stimulation of the RAAS). Classically, hyperaldosteronism presents with hypertension, hypokalemia, and metabolic alkalosis. Hyperaldosteronism
  • CKD CKD Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension and diabetes are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Chronic Kidney Disease
  • Obstructive sleep apnea Obstructive sleep apnea Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea ( OSA OSA Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea)
  • Pheochromocytoma Pheochromocytoma Pheochromocytoma is a catecholamine-secreting tumor derived from chromaffin cells. The majority of tumors originate in the adrenal medulla, but they may also arise from sympathetic ganglia (also referred to as paraganglioma). Symptoms are associated with excessive catecholamine production and commonly include hypertension, tachycardia, headache, and sweating. Pheochromocytoma
  • Cushing syndrome
  • Coarctation of the aorta Coarctation of the aorta Coarctation of the aorta is a narrowing of the aorta between the aortic arch and the iliac bifurcation commonly around the point of insertion of the ductus arteriosus. Coarctation of the aorta is typically congenital and the clinical presentation depends on the age of the patient. Coarctation of the Aorta

Etiology

• Head trauma Head trauma Head trauma occurs when external forces are directed to the skull and brain structures, resulting in damage to the skull, brain, and intracranial structures. Head injuries can be classified as open (penetrating) or closed (blunt), and primary (from the initial trauma) or secondary (indirect brain injury), and range from mild to severe and life-threatening. Head Trauma
• Blood pressure medication noncompliance
• Suboptimal therapy
• Rebound hypertension
• Emotional disturbance
• Hyperthyroidism Hyperthyroidism Thyrotoxicosis refers to the classic physiologic manifestations of excess thyroid hormones and is not synonymous with hyperthyroidism, which is caused by sustained overproduction and release of T3 and/or T4. Graves' disease is the most common cause of primary hyperthyroidism, followed by toxic multinodular goiter and toxic adenoma. Thyrotoxicosis and Hyperthyroidism
• Extracellular volume expansion: 
  • High-sodium diet
  • Underlying renal insufficiency
  • Sodium retention (side effect of vasodilators)
• Use of stimulants Stimulants Stimulants are used by the general public to increase alertness and energy, decrease fatigue, and promote mental focus. Stimulants have medical uses for individuals with ADHD and sleep disorders, and are also used in combination with analgesics in pain management. Stimulants:
  • Cocaine
  • Methamphetamine
  • Caffeine 
  • Nicotine
• Medications that cause increased blood pressure:
  • NSAIDs
  • Sympathomimetics:
    • Weight-loss drugs
    • Decongestants
    • Amphetamines
  • Glucocorticoids Glucocorticoids Glucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs. Glucocorticoids
  • Oral contraceptives
  • Antidepressants
  • Calcineurin inhibitors
• Causes of secondary hypertension

Epidemiology

• Difficult to assess because of inconsistent coding practices among practitioners/institutions
• Depends on the underlying cause

Pathophysiology

• Poorly understood
• Depends on the underlying cause

Clinical Presentation

Regardless of the manifestation of severe hypertension, by definition, the individual will have a blood pressure ≥ 180 mm Hg systolic and/or ≥ 120 mm Hg diastolic.

Hypertensive urgency

• Blood pressure ≥ 180 mm Hg systolic and/or ≥ 120 mm Hg diastolic
• Asymptomatic or vague/minimal symptoms:
  • Headache
  • Fatigue
  • Flushing
  • Blurred vision

Hypertensive emergency

• Blood pressure ≥ 180 mm Hg systolic and/or ≥ 120 mm Hg diastolic
• Potential symptoms:
  • Chest pain
  • Shortness of breath
  • Visual disturbance
  • Focal neurologic symptoms
  • Altered mental status
  • Hematuria
  • Anuria
• Evidence of myocardial ischemia or MI MI MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction:
  • Diagnostic ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Normal Electrocardiogram (ECG) changes
  • Elevated cardiac enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body's constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes
  • Acute and/or decompensated heart failure
• Evidence of cerebrovascular accident Cerebrovascular accident An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke:
  • Focal neurologic deficits
  • CT/MRI findings indicative of cerebral ischemia and/or bleeding
• Evidence of acute/acute-on-chronic renal failure:
  • Acute uremia
  • Acidosis/alkalosis
  • Abnormal electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes

Evaluation and Diagnosis

During the initial assessment of a individual with severe hypertension, it is imperative to exclude chronic target-organ damage. Severe elevations in blood pressure should be quickly confirmed with repeat measurement.

History

Particular focus on risk factors for end-organ vascular events:

• Acute head injury
• Use of stimulant drugs (cocaine, methamphetamine)
• Known myocardial ischemia
• Known cerebrovascular ischemia
• Known arterial deformity:
  • Abdominal aortic aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Extremity and Visceral Aneurysms ( AAA AAA An aortic aneurysm is the abnormal dilation of a segment of the aorta. Abdominal aortic aneurysm is the most common aortic aneurysm, occurring frequently in the infrarenal area. Most aneurysms are asymptomatic, but can cause compression of surrounding structures or rupture, which is a life-threatening emergency. Abdominal Aortic Aneurysms)
  • Cerebral aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Extremity and Visceral Aneurysms
  • Arteriovenous malformation (AVM)
  • Recent vascular surgery Vascular surgery Vascular surgery is the specialized field of medicine that focuses on the surgical management of the pathologies of the peripheral circulation. The main goal of most vascular procedures is to restore circulatory function to the affected vessels by relieving occlusions or by redirecting blood flow (e.g., bypass). Vascular Surgery
  • RAS RAS Renal artery stenosis (RAS) is the narrowing of one or both renal arteries, usually caused by atherosclerotic disease or by fibromuscular dysplasia. If the stenosis is severe enough, the stenosis causes decreased renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS) and leads to renovascular hypertension (RVH). Renal Artery Stenosis
• Multiple vascular risk factors:
  • Age
  • Family history
  • Smoking
  • Diabetes
  • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension
  • Dyslipidemia
  • Obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity
  • Sedentary lifestyle
  • OSA OSA Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea

Symptoms of end-organ dysfunction:

• Headache
• Fatigue
• Blurred vision
• Chest pain
• Shortness of breath
• Nausea/vomiting ( increased intracranial pressure Increased Intracranial Pressure Normal intracranial pressure (ICP) is defined as < 15 mm Hg, whereas pathologically increased ICP is any pressure ≥ 20 mm Hg. Increased ICP may result from several etiologies, including trauma, intracranial hemorrhage, mass lesions, cerebral edema, increased CSF production, and decreased CSF absorption. Increased Intracranial Pressure (ICP))
• Visual disturbance
• Focal neurologic symptoms
• Altered mental status
• Acute severe back pain Back pain Back pain is a common complaint among the general population and is mostly self-limiting. Back pain can be classified as acute, subacute, or chronic depending on the duration of symptoms. The wide variety of potential etiologies include degenerative, mechanical, malignant, infectious, rheumatologic, and extraspinal causes. Back Pain ( aortic dissection Aortic dissection Aortic dissection occurs due to shearing stress from pulsatile pressure causing a tear in the tunica intima of the aortic wall. This tear allows blood to flow into the media, creating a "false lumen." Aortic dissection is most commonly caused by uncontrolled hypertension. Aortic Dissection)
• Hematuria
• Anuria

Physical examination

• Blood pressure evaluation:
  • Standard blood pressure measurement with a manual sphygmomanometer at regular intervals is appropriate for low-risk individuals.
  • Higher-risk individuals may need continuous monitoring with an automatic sphygmomanometer with a digital display.
  • Individuals requiring urgent and controlled blood pressure lowering with IV antihypertensives may benefit from the placement of an intraarterial catheter for continuous blood pressure monitoring.
• Mental status:
  • Agitation
  • Delirium Delirium Delirium is a medical condition characterized by acute disturbances in attention and awareness. Symptoms may fluctuate during the course of a day and involve memory deficits and disorientation. Delirium
  • Stupor
  • Seizure
  • Coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma
• Focal neurologic findings:
  • Visual loss
  • Limb paresis/paralysis
  • Speech deficit
• Ophthalmic exam Ophthalmic exam A comprehensive examination of the eyes and their functions is important for all individuals with ocular symptoms, and to screen for visual acuity, glaucoma, and retinal pathology. A routine examination includes testing for visual acuity, peripheral vision, and color vision, plus an examination of the external eye, conjunctiva, sclera, iris, pupil, and extraocular movements. Ophthalmic Exam:
  • Hemorrhages
  • Exudates
  • Papilledema
• Signs of cardiac decompensation:
  • Jugular venous distention (JVD)
  • Palpitations/abnormal rhythm
  • New murmur
  • New gallop
  • Pulmonary rales
  • Peripheral edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
• Miscellaneous:
  • Abdominal bruit ( AAA AAA An aortic aneurysm is the abnormal dilation of a segment of the aorta. Abdominal aortic aneurysm is the most common aortic aneurysm, occurring frequently in the infrarenal area. Most aneurysms are asymptomatic, but can cause compression of surrounding structures or rupture, which is a life-threatening emergency. Abdominal Aortic Aneurysms or RAS RAS Renal artery stenosis (RAS) is the narrowing of one or both renal arteries, usually caused by atherosclerotic disease or by fibromuscular dysplasia. If the stenosis is severe enough, the stenosis causes decreased renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS) and leads to renovascular hypertension (RVH). Renal Artery Stenosis)
  • Carotid or femoral bruit (suggests atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis)

Diagnostic tests Diagnostic tests Diagnostic tests are important aspects in making a diagnosis. Some of the most important epidemiological values of diagnostic tests include sensitivity and specificity, false positives and false negatives, positive and negative predictive values, likelihood ratios, and pre-test and post-test probabilities. Epidemiological Values of Diagnostic Tests

• ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Normal Electrocardiogram (ECG)
• Urine studies:
  • Urinalysis
  • 24-hour urine collection:
    • Protein
    • Catecholamines/metanephrines for pheochromocytoma
    • Sodium excretion
• Blood chemistry:
  • Electrolytes
  • Serum creatinine
  • Cardiac biomarkers
  • Serum aldosterone

Imaging for ischemia/vascular compromise

• Chest X-ray:
  • Pulmonary edema Pulmonary edema Pulmonary edema is a condition caused by excess fluid within the lung parenchyma and alveoli as a consequence of a disease process. Based on etiology, pulmonary edema is classified as cardiogenic or noncardiogenic. Patients may present with progressive dyspnea, orthopnea, cough, or respiratory failure. Pulmonary Edema
  • Cardiac enlargement
  • Widened mediastinum Mediastinum The mediastinum is the thoracic area between the 2 pleural cavities. The mediastinum contains vital structures of the circulatory, respiratory, digestive, and nervous systems including the heart and esophagus, and major thoracic vessels. Mediastinum and Great Vessels
  • Pulmonary edema Pulmonary edema Pulmonary edema is a condition caused by excess fluid within the lung parenchyma and alveoli as a consequence of a disease process. Based on etiology, pulmonary edema is classified as cardiogenic or noncardiogenic. Patients may present with progressive dyspnea, orthopnea, cough, or respiratory failure. Pulmonary Edema
• CT/MRI brain:
  • Cerebral ischemia
  • Cerebral hemorrhage
• CT chest/abdomen:
  • Thoracic aortic dissection Aortic dissection Aortic dissection occurs due to shearing stress from pulsatile pressure causing a tear in the tunica intima of the aortic wall. This tear allows blood to flow into the media, creating a "false lumen." Aortic dissection is most commonly caused by uncontrolled hypertension. Aortic Dissection
  • Abdominal aortic aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Extremity and Visceral Aneurysms dissection

Management

Rate of reduction for elevated blood pressure

• Target blood pressure should be achieved over a period of hours to days.
• Slower reductions may be needed in older individuals with an increased risk of cerebral or myocardial ischemia.

Target blood pressure

• Blood pressure should be slowly reduced to < 160/< 100 mm Hg.
• Mean arterial pressure (MAP) should not be lowered ＞25%–30% in the 1st few hours.
• Long-term reductions back to previous therapeutic target (i.e., ≤ 130/80 mm Hg)

No evidence of end-organ damage

Outpatient management:

•  Outcomes may be poor:
  • High rate of loss to follow-up soon after evaluation
  • High rate of return to the ED for recurrent uncontrolled hypertension within 3 months
• May be appropriate if:
  • No evidence of end-organ damage
  • Blood pressure was previously controlled on an antihypertensive regimen.
  • Individual or their caregiver is reliable for monitoring blood pressure and ensuring that medications are taken.

ED management:

• Move individual to a quiet room: can lead to a fall in systolic pressure of ≥ 10–20 mm Hg 
• Determine time course of blood pressure lowering:
  • Balance between 2 concerns:
    • Blood pressure ↓ too quickly, potential inability for autoregulation to maintain end-organ tissue perfusion
    • Blood pressure ↓ too slowly, potential risk of imminent cardiovascular events 
• If blood pressure needs to be lowered quickly (hours):
  • Includes individuals with high risk:
    • Imminent coronary or cerebral ischemia
    • Known renal artery stenosis
    • Known existing cerebral or aortic aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Extremity and Visceral Aneurysms
  • Oral clonidine (rapid-acting)
  • Oral captopril (rapid-acting)
  • Oral or sublingual nitrates Nitrates Nitrates are a class of medications that cause systemic vasodilation (veins > arteries) by smooth muscle relaxation. Nitrates are primarily indicated for the treatment of angina, where preferential venodilation causes pooling of blood, decreased preload, and ultimately decreased myocardial O2 demand. Nitrates (rapid-acting)
  • Oral hydralazine (rapid-acting)
  • Consider admitting the individual for observation and blood pressure medication titration.
  • Consider discharge home with short-interval follow-up.
• If blood pressure needs to be lowered slowly (days):
  • Previously diagnosed hypertension: 
    • Previously controlled → resume previous regimen
    • Previously suboptimally controlled → increase doses for previous regimen or add a new agent 
  • If new diagnosis:
    • Amlodipine 
    • Chlorthalidone 
    • Beta-blockers if the individual has a comorbid indication for beta-blockade (e.g., heart failure)
    • ACEis if the individual has a comorbid indication for ACE inhibition (e.g., diabetes)
    • Combination therapy may be considered.
    • Consider hospital admission for medication titration.
    • Consider discharge home with short-interval follow-up.
• Prior to discharge:
  • Ensure:
    • Short-interval follow-up with primary care physician ( PCP PCP Pneumocystis jiroveci is a yeast-like fungus causing pneumocystis pneumonia (PCP) in immunocompromised patients. Pneumocystis pneumonia is spread through airborne transmission and classically affects patients with AIDS, functioning as an AIDS-defining illness. Patients may present with insidious onset of fever, chills, dry cough, chest pain, and shortness of breath. Pneumocystis jiroveci/Pneumocystis Pneumonia (PCP)) or appropriate specialist
    • Prescription given for any new medications
  • Counsel:
    • Importance of adherence to blood pressure medication regimen
    • Importance of dietary sodium restriction

Evidence of end-organ damage

• Admit individual to ICU:
  • For intensive monitoring
  • For rapid intervention in the event of decompensation
  • For rapidly titratable IV delivery of blood pressure medications
• Rapid lowering of blood pressure is generally not advised.
  • Risk of ischemia if vascular physiology has habituated to higher blood pressure
  • 10%–20% lowering of MAP in the 1st hour
  • Additional lowering of MAP 5%–15% over the next 24 hours
• Exceptions:
  • Ischemic stroke: Do NOT initiate blood pressure–lowering measures unless:
    • Blood pressure > 185/110 mm Hg if candidate for reperfusion
    • Blood pressure > 220/120 mm Hg if not candidate for reperfusion
  • Aortic dissection: Initiate rapid systolic blood pressure lowering.
  • Intracerebral hemorrhage Intracerebral Hemorrhage Intracerebral hemorrhage (ICH) refers to a spontaneous or traumatic bleed into the brain parenchyma and is the 2nd-most common cause of cerebrovascular accidents (CVAs), commonly known as stroke, after ischemic CVAs. Intracerebral Hemorrhage: DO initiate rapid systolic blood pressure lowering: 
    • Target blood pressure 140 mm Hg if presenting blood pressure is 150–220 mm Hg
    • Target blood pressure 140–160 mm Hg if presenting blood pressure is >220 mm Hg
• Appropriate specialist consultation:
  • Interventional cardiology
  • Neurology/ neurosurgery Neurosurgery Neurosurgery is a specialized field focused on the surgical management of pathologies of the brain, spine, spinal cord, and peripheral nerves. General neurosurgery includes cases of trauma and emergencies. There are a number of specialized neurosurgical practices, including oncologic neurosurgery, spinal neurosurgery, and pediatric neurosurgery. Neurosurgery
  • Vascular surgery
  • Interventional radiology
  • Nephrology
• Therapeutic IV blood pressure agents:
  • Beta-blockers:
    • Labetalol
    • Esmolol
  • Calcium channel blockers Calcium Channel Blockers Calcium channel blockers (CCBs) are a class of medications that inhibit voltage-dependent L-type calcium channels of cardiac and vascular smooth muscle cells. The inhibition of these channels produces vasodilation and myocardial depression. There are 2 major classes of CCBs: dihydropyridines and non-dihydropyridines. Class 4 Antiarrhythmic Drugs (Calcium Channel Blockers):
    • Nicardipine
    • Clevidipine
    • Felodipine
  • Nitrates:
    • Nitroprusside
    • Nitroglycerine
  • Others:
    • Phentolamine
    • Hydralazine
• After 8–24 hours of stable blood pressure control:
  • Transition to oral agents
  • Wean IV agents
  • Transition out of ICU
  • Discharge planning as above.

Clinical Relevance

• Labile (paroxysmal) hypertension: marked elevations in blood pressure that are recurrent, sudden, and transient. Labile hypertension is linked to sympathetic hyperstimulation, though the link is poorly understood. Treatment is with adrenergic blocking agents (i.e., beta-blockers, alpha-blockers).
• Secondary hypertension: resistant hypertension with an identifiable and potentially treatable etiology. Includes RAS RAS Renal artery stenosis (RAS) is the narrowing of one or both renal arteries, usually caused by atherosclerotic disease or by fibromuscular dysplasia. If the stenosis is severe enough, the stenosis causes decreased renal blood flow, which activates the renin-angiotensin-aldosterone system (RAAS) and leads to renovascular hypertension (RVH). Renal Artery Stenosis, primary hyperaldosteronism Hyperaldosteronism Hyperaldosteronism is defined as the increased secretion of aldosterone from the zona glomerulosa of the adrenal cortex. Hyperaldosteronism may be primary (resulting from autonomous secretion), or secondary (resulting from physiological secretion due to stimulation of the RAAS). Classically, hyperaldosteronism presents with hypertension, hypokalemia, and metabolic alkalosis. Hyperaldosteronism, CKD CKD Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension and diabetes are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Chronic Kidney Disease, OSA OSA Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea, pheochromocytoma, Cushing syndrome, coarctation of the aorta. Treatment depends on the specific cause. 
• Head trauma Head trauma Head trauma occurs when external forces are directed to the skull and brain structures, resulting in damage to the skull, brain, and intracranial structures. Head injuries can be classified as open (penetrating) or closed (blunt), and primary (from the initial trauma) or secondary (indirect brain injury), and range from mild to severe and life-threatening. Head Trauma: complex cascade of neurohormonal factors resulting from a traumatic brain injury can cause severe hypertension. This cascade likely represents compensatory mechanisms to maintain cerebral perfusion in the setting of increased intracranial pressure Increased Intracranial Pressure Normal intracranial pressure (ICP) is defined as < 15 mm Hg, whereas pathologically increased ICP is any pressure ≥ 20 mm Hg. Increased ICP may result from several etiologies, including trauma, intracranial hemorrhage, mass lesions, cerebral edema, increased CSF production, and decreased CSF absorption. Increased Intracranial Pressure (ICP). The balance between maintenance of cerebral perfusion and prevention of cerebrovascular events makes treatment of elevated blood pressure with head trauma controversial.  
• Hypertensive encephalopathy: dramatic change in the level of consciousness, cognition, or personality in the setting of severe hypertension and attributable to cerebral edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema. Management includes aggressive but careful lowering of the blood pressure and immediate neurologic/neurosurgical consultation to avoid or minimize cerebrovascular events and/or permanent brain damage.  
• Hypertensive retinopathy Hypertensive retinopathy Hypertension has many adverse effects on the eye, of which retinopathy is the most common presentation. Hypertensive retinopathy consists of retinal vascular changes that develop as a direct effect of elevated blood pressure. In acute increases of blood pressure, autoregulation results in retinal arteriolar narrowing. Hypertensive Retinopathy: characterized by retinal hemorrhages, exudates, and papilledema in the setting of severe hypertension. Management consists of aggressive but careful lowering of the blood pressure and immediate ophthalmologic consultation to avoid or minimize vision loss. 
• Hypertensive heart disease: Cardiomyopathy Cardiomyopathy Cardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease). Overview of Cardiomyopathies is directly attributable to the physiologic compensations the myocardium must make to maintain cardiac output in the face of chronically elevated afterload and may result in systolic dysfunction, diastolic dysfunction, valvular dysfunction, increased arrhythmogenic potential, and myocardial ischemia (even with normal coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries). Management consists of blood pressure optimization and prevention of heart failure, arrhythmia, and ischemia. 
• Hypertensive nephropathy: progressive nephrosclerosis involving the renal vasculature, glomeruli, and tubulointerstitial elements in the setting of uncontrolled hypertension. The long-term result is progressive loss of kidney function ultimately manifesting as end-stage renal disease that may require hemodialysis. 
• Obstetric hypertensive complications: chronic hypertension, gestational hypertension, preeclampsia, eclampsia, and HELLP syndrome are the obstetric complications of pregnancy Pregnancy Pregnancy is the time period between fertilization of an oocyte and delivery of a fetus approximately 9 months later. The 1st sign of pregnancy is typically a missed menstrual period, after which, pregnancy should be confirmed clinically based on a positive β-hCG test (typically a qualitative urine test) and pelvic ultrasound. Pregnancy: Diagnosis, Maternal Physiology, and Routine Care that can pose health risks to the mother and fetus. Management includes control of blood pressure and delivery of the fetus.