Hypertensive crisis resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ayokunle Olubaniyi, M.B,B.S [2]; Rim Halaby, M.D. [3]

Hypertensive Crisis Resident Survival Guide Microchapters
Overview
Causes
FIRE
Diagnosis
Treatment Initial Specific
Do's
Don'ts

Overview

Hypertensive crisis is a term used to describe an acute elevation in the blood pressure which may or may not be associated with end-organ damage. Hypertensive crisis includes both hypertensive emergency and hypertensive urgency. Noncompliance with antihypertensive medications is the most common cause of hypertensive crisis.

Classification

Hypertensive crisis can be further classified as hypertensive urgency and hypertensive emergency based on either the absence or presence of acute end-organ damage.

Hypertensive Urgency

Hypertensive urgency is an acute severe elevation in the blood pressure without any evidence of acute end-organ damage.

Hypertensive Emergency

Hypertensive emergency mostly falls into stage 2 of hypertension (systolic blood pressure greater >160 mm Hg or diastolic blood pressure >100 mmHg). It is usually an acute severe elevation in the blood pressure (systolic blood pressure ≥ 180 mm Hg, or diastolic blood pressure ≥ 120 mmHg) complicated by acute end-organ dysfunction, such as hypertensive encephalopathy, eclampsia, dissecting aortic aneurysm, acute left ventricular failure with pulmonary edema, acute myocardial infarction, acute renal failure, or symptomatic microangiopathic hemolytic anemia.

Causes

Life Threatening Causes

Hypertensive crisis is a life-threatening condition and must be treated as such irrespective of the cause.

Common Causes

• Antihypertensive medications withdrawal ( beta blockers, clonidine)
• Noncompliance with antihypertensive medications
• Pheochromocytoma
• Side effects of monoamine oxidase inhibitors
• Stimulants (cocaine, methamphetamine, phencyclidine)

It can develop de novo or can complicate essential or secondary hypertension. Click here for the complete list of causes of chronic hypertension.

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients in need of immediate intervention.
Boxes in the red color signify that an urgent management is needed.

Identify cardinal findings that suggest any of the following: ❑ Cerebral infarction and Intracerebral hemorrhage ❑ Lateralizing signs ❑ Subarachnoid hemorrhage ❑ Sudden severe headache ❑ Hypertensive encephalopathy ❑ Altered level of consciousness ❑ Hypertensive retinopathy (retinal hemorrhage and papilledema) ❑ Seizures ❑ Acute left ventricular failure ❑ Myocardial infarction ❑ Chest pain radiating to the jaw and left arm ❑ Consider atypical presentations as dyspnea, cough, or fatigue ❑ Aortic dissection ❑ Severe chest pain, unequal pulses, widened mediastinum ❑ Acute pulmonary edema ❑ Severe dyspnea, decreased breath sounds and rales ❑ Acute renal failure

Measure the blood pressure

BP ≥ 180/110

BP < 180/110

Does the patient have any evidence of end organ damage?

❑ Continue with the complete diagnostic approach of chronic hypertension ❑ Proceed with the specific managemnt of the different causes

Yes

No

Hypertensive emergency

Hypertensive urgency

Identify alarming signs and symptoms: ❑ Tachycardia ❑ Hypotension ❑ Loss of consciousness ❑ Tachypnea

❑ Consider admission for observation ❑ Consider treatment as an outpatient

Click here for complete management of hypertensive crisis

Complete Diagnostic Approach

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.

Characterize the symptoms: ❑ A new complex of symptoms related to elevated blood pressure ❑ Central nervous system: (symptoms suggestive of cerebral infarction, intracerebral or subarachnoid hemorrhage, or hypertensive encephalopathy) ❑ Severe headache ❑ Altered level of consciousness ❑ Confusion or agitation ❑ Difficulty in speaking or understanding ❑ Dysphagia ❑ Nausea or vomiting ❑ Dizziness ❑ Weakness or numbness ❑ Loss of balance or coordination ❑ Seizures ❑ Stupor or coma ❑ Asterixis ❑ Tremors ❑ Eyes: (symptoms suggestive of hypertensive retinopathy) ❑ Pain ❑ Blurred or loss of vision ❑ Cardiovascular system: (symptoms suggestive of acute left ventricular failure, myocardial infarction, or aortic dissection) ❑ Chest pain ❑ Dyspnea ❑ Palpitations ❑ Back pain ❑ Pleuritic pain ❑ Respiratory system: (symptoms suggestive of acute pulmonary edema) ❑ Cough with or without frothy sputum ❑ Cough with or without blood ❑ Dyspnea ❑ Diaphoresis ❑ Orthopnea ❑ Paroxysmal nocturnal dyspnea ❑ Wheezing ❑ Renal: (symptoms suggestive of acute renal failure) ❑ Hematuria ❑ Reduced urinary output ❑ Others: ❑ Anxiety ❑ Eclampsia (during pregnancy) ❑ Epistaxis

Consider the diagnosis of hypertensive crisis

Obtain a detailed history: History of ❑ Hypertension ❑ Onset and duration ❑ Previous anti-hypertensive medications with dosing and duration of use ❑ Current anti-hypertensive medications with dosing duration of use ❑ Compliance to anti-hypertensive medications ❑ Time since the last dose of anti-hypertensive medication ❑ Other prescribed or over-the-counter medications (eg, monoamine oxidase inhibitors, sympathomimetic agents) ❑ Recreational drug use (eg, methamphetamine, cocaine, phencyclidine ❑ Any cerebrovascular disease ❑ Any cardiac disease ❑ Any renal disease ❑ Other medical problems (eg, thyroid disease, Cushing disease, systemic lupus)

Examine the patient: Vitals ❑ Pulse ❑ Tachycardia ❑ Unequal pulse (suggestive of aortic dissection) ❑ Should be measured in all extremities ❑ Respiration ❑ Tachypnea (suggestive of left sided heart failure or pulmonary edema) ❑ Blood pressure ❑ Hypertension (systolic blood pressure ≥ 180 mm Hg, or diastolic blood pressure ≥ 120 mmHg) ❑ Measured by the physician ❑ Measured in both arms ❑ Measured with appropriate cuff size (small cuffs gives falsely high readings) ❑ Pulse oximetry ❑ Eye ❑ Abnormal extra-ocular movements ❑ Pupils not reactive to light ❑ Abnormal findings on ophthalmoscopic exam Neck ❑ Elevated jugular venous pressure (suggestive of heart failure) ❑ Carotid bruits (suggestive of aortic stenosis and astherosclerotic vessels) Respiratory examination ❑ Assessment of respiratory effort (e.g., intercostal retractions, use of accessory muscles) ❑ Auscultation (rales, reduced breath sounds, egophony) (all suggestive of pulmonary edema) Cardiovascular examination ❑ Auscultation (abnormal sounds, murmurs) (suggestive of acute heart failure or previous heart disease) ❑ Abdominal aorta (e.g., size, bruits) (suggestive of aortic dissection) ❑ Pedal pulses (e.g., pulse amplitude) Abdominal examination ❑ looking for pulsatile masses, tenderness, bruits (suggestive of aortic dissection or renal artery involvement precipitating acute renal failure) Neurological examination Full neurological examination searching for laterlaizing signs (suggestive of cerebrovascular accident) ❑ Glasgow coma scale ❑ Test cranial nerves with notation of any deficits ❑ Deep tendon reflexes with notation of any pathologic reflexes (e.g., Babinksi) ❑ Clonus ❑ Hyperactive reflexes ❑ Sensation (e.g., by touch, pin, vibration, proprioception)

Order Labs: ❑ CBC ❑ Electrolytes ❑ BUN ❑ Creatinine ❑ EKG (in case of chest pain) ❑ CXR (in case of chest pain or dyspnea) ❑ CT or MRI (in case of suspicion of aortic dissection) Consider additional tests based on each patient's presentation: ❑ Urine electrolytes, creatinine, protein ❑ CT/MRI ❑ Renal ultrasound + doppler ❑ TSH, free T3, free T4 ❑ Serum cortisol ❑ Serum aldosterone ❑ Serum renin ❑ 24-hr urinary catecholamine & metanephrine ❑ Serum parathyroid hormone ❑ Urine and serum toxicology screen ❑ Urine pregnancy test ❑ ANA/ESR/CRP/anti-dsDNA/anti-smith/rheumatoid factor/p-ANCA/c-ANCA

Treatment

Shown below is an algorithm summarizing the management of hypertensive crisis according to the seventh report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure: the JNC 7 report.

Initial Approach

Is there any evidence of end organ damage?

YES

NO

Hypertensive emergency

Hypertensive urgency

❑ Admit to ICU

❑ Treat as outpatient or admit for observation

❑ Monitor the blood pressure closely ❑ Intra-arterial blood pressure monitoring in severely-ill patients ❑ Assess volume status ❑ IV N/S if volume depleted to prevent precipitous fall in blood pressure following administration of antihypertensives ❑ Commence continuous infusion of short acting IV antihypertensives based on patient's end organ damage ❑ Change IV medications to oral when blood pressure is stable NB - Not more than 25% reduction in blood pressure within the 1st hour; when blood pressure is stable, reduce to 160/100-110 mmHg within the next 2-6 hours ❑ When the patient is stable and the blood pressure is well tolerated, reduce the blood pressure to normal within 24-48 hours

❑ Administer Oral antihypertensives ❑ Monitor the patient clinically within the first few hours of commencing medications NB - Gradual blood pressure reduction over 24 - 48 hours

Failure to control the blood pressure ❑ Consider a combination of antihypertensive medications

Good control of the blood pressure ❑ Review old or start new medications ❑ Modify risk factors ❑ Schedule a follow up

Intravenous Antihypertensive Drugs

Shown below is a table of the IV antihypertensive drugs and their appropriate doses.

Drug	Dose
Clevidipine	1 to 2 mg/h as IV infusion, max 16 mg/h
Enalaprilat	1.25–5 mg every 6 hrs IV
Fenoldopam	0.1–0.3 µg/kg per min IV infusion
Hydralazine	10–20 mg IV
Nicardipine	5–15 mg/h IV
Nitroglycerin	5–100 µg/min as IV infusion
Nitroprusside	0.25–10 µg/kg/min as IV infusion
Esmolol	250–500 µg/kg/min IV bolus, then 50–100 µg/kg/min by infusion May repeat bolus after 5 min or increase infusion to 300 µg/min
Labetalol	20–80 mg IV bolus every 10 min 0.5–2.0 mg/min IV infusion
Phentolamine	5–15 mg IV bolus

Oral Antihypertensive Drugs

Shown below is a table of the oral antihypertensive drugs and their appropriate doses.

Drug	Dose
Captopril	12.5 to 25 mg PO or SL, repeat as needed. max dose - 50 mg PO
Clonidine	0.1-0.2 mg PO x 1, then 0.05 to 0.1 mg/1-2 hrs. Max dose - 0.6 to 0.7 mg
Labetalol	200 mg PO, then 200 mg/hr until desired effect. Max dose - 1200 mg

• Other agents to consider include:

1. PO frusemide 20mg (repeat as necessary)
2. PO nifedipine SR 30mg, single dose
3. PO felodipine 5 mg, single dose

Management of Specific Hypertensive Emergencies

Hypertensive emergencies	Preferred agents
Aortic dissection	Labetalol, or nicardipine + esmolol, or nitroprusside + esmolol or nitroprusside + IV metoprolol Note: Administer beta blocker to control the heart rate before initiating a vasodilator e.g. nitroprusside Reduce blood pressure to 120 mmHg within 20 minutes with protection against reflex tachycardia.
Acute pulmonary edema / systolic dysfunction	Nitroglycerin + (Nicardipine or, fenoldopam, or nitroprusside) + loop diuretic
Acute pulmonary edema / diastolic dysfunction	Low-dose Nitroglycerin + (esmolol, metoprolol, labetalol, or verapamil) + loop diuretic
Acute coronary syndrome	Nitroglycerin + (labetalol or esmolol)
Hypertensive emergency with acute or chronic renal failure	Nicardipine or fenoldopam
Hypertensive encephalopathy	Nicardipine, labetalol, fenoldopam Note: the blood pressure should not be lowered by more than 25%
Pre-eclampsia / eclampsia	Labetalol or nicardipine
Sympathetic crisis / cocaine overdose	Benzodiazepine + (verapamil, diltiazem, or nicardipine) Note: Beta blockers should NOT be administered alone to prevent un-opposed alpha-adrenergic stimulation
Cerebrovascular accident	Nicardipine, labetalol, fenoldopam, or clevidipine Note: An expert's judgement is required to determine if the blood pressure should be lowered.
Withdrawal of antihypertensive therapy e.g. clonidine or propanolol	Re-administer the discontinued drug; phentolamine, nitroprusside, or labetalol, if necessary

Dos

• Hypertensive emergencies are best managed with a continuous infusion of short-acting titratable antihypertensive agents.
• Avoid sublingual and intramuscular routes of drug administration due to their unpredictable pharmacodynamics.
• Assess the patient' volume status before initiating intravenous vasodilators to prevent or minimize a substancial fall in blood pressure.

Don'ts

• Don't consider nifedipine, nitroglycerin and hydralazine as first-line therapies in the management of hypertensive crises due to their potential toxicities and adverse effects.
• Don't use intramuscular or sublingual antihypertensive medications in the case of hypertensive emergency.
• Don't use rapid acting antihypertensive if the patient is not in an ICU setting.

References