Hypertensive Emergencies

by Sadiye Yolcu

Introduction

Systemic hypertension is a common medical problem. It affects over 1 million people worldwide. ER clinicians commonly encounter this problem. Rapid diagnosis, evaluation, differentiation of hypertensive emergencies and hypertensive urgencies, and appropriate treatment of these conditions are required to prevent morbidity and mortality.

The levels above 180 systolic BP and 110 diastolic BP are considered very dangerous which may cause end-organ damage such as intracranial bleeding, aortic dissection, renal failure, etc. Having end-organ damage is the hypertensive emergency. Having high blood pressure without any signs of end-organ damage is the hypertensive urgency. Retinal hemorrhage or exudates/papilledema associated with hypertension is defined as malignant hypertension.

Hypertensive emergencies require action within one hour to abolish the risks of developing complications. Hypertensive urgencies are defined as situations requiring actions within 24 hours and yet do not compromise the risk of developing complications within that period.

Hypertensive emergencies include

Acute aortic dissection
Acute coronary syndrome
Acute heart failure
Acute renal failure
Eclampsia
Hypertensive encephalopathy
Intracerebral/subarachnoid hemorrhage
Pheochromocytoma,
Sympathomimetic drug use (cocaine etc.),
Stroke

Hypertensive urgencies include

Diastolic tension ≥140 mmHg without complication
Malign hypertension without complication
Perioperative hypertension
Pheochromocytoma,
Sympathomimetic drug use (cocaine, etc.)

Case Presentation

A 68-year-old man with tearing chest pain presented to the emergency department. He had a history of coronary artery disease and hypertension. BP: 220/160 mmHg, HR: 105 bpm, RR: 20/min, T: 37, SpO2: 96% in room air. In the initial evaluation, airway and breathing were intact. Diastolic murmur was heard on cardiac auscultation, and pulses were positive in all extremities. He has a normal mental state (GCS 15) and no lateralized motor deficit. A difference in systolic blood pressure was measured between upper extremities (220/160 vs. 180/140 mmHg). ECG showed nonspecific ST-T changes and sinus tachycardia.

Critical Bedside Actions and General Approach

The priority should be given to initial stabilization of the patient (C-A-B) as other critically ill patients. Depending on patients’ symptoms in addition to high blood pressure, the cardiac monitorization, oxygen (if necessary), two large bore IV access should be established and blood samples (CBC, BUN, Cr, coagulation, cardiac markers, type, and cross-match) sent to the laboratory. ECG and chest x-ray should be ordered.

Lowering BP should be balanced with the level of BP, patient’s symptoms as well as harm-benefit situation.

Differential Diagnosis

The most critical step in the differential diagnosis is the definition of the hypertensive situation (emergency or urgency). Suspicion of hypertensive emergencies aligns with hypertension and end-organ damage. Depending on patient symptoms and findings, hypertensive emergencies differentials include severe problems such as intracranial hemorrhage, ischemic stroke, aortic dissection, acute MI, AAA rupture, heart failure, renal failure, limb or organ ischemia, etc. In addition to these end-organ damages, other differentials (seizure, brain tumor, encephalitis, encephalopathy, drug overdose, etc.) should also be considered.

History and Physical Examination Hints

The previous medical history of the patient (chronic diseases, antihypertensive drugs usage, previous end-organ compromise, etc.) should be taken. Chest pain for myocardial infarction, aortic dissection, dyspnea for pulmonary edema, headache, mental status, seizure for hypertensive encephalopathy should be asked.

The patients present mostly with ischemic stroke, pulmonary edema, hypertensive encephalopathy, or congestive heart failure. Therefore, history and physical exam should be focused on these problems during the initial and secondary evaluation. In the physical examination, measure the blood pressure from both arms and assesses the patient for end-organ compromise (neurologic-ophthalmologic-cardiac).

Each of these hints was given in the specific disease chapters. Therefore, we advise you to review those chapters too.

Emergency Diagnostic Tests and Interpretation

An electrocardiogram (ECG) and chest X-ray should be performed. ECG may show arrhythmias, nonspecific ST-T changes or obvious acute MI findings. The chest x-ray may give hints about aortic dissection, aneurysm, pulmonary edema.

What is your opinion about the chest x-ray below?

Bedside ultrasonography may help to diagnose some critical pathologies timely. These are pulmonary edema, aortic aneurysm or dissection, heart failure, and increased intracranial pressure.

What is your opinion about the transthoracic ultrasound below?

Blood urea nitrogen (BUN), electrolytes, complete blood count (CBC), liver-renal function tests, coagulation parameters, cardiac enzymes and urine analyses should be checked. BUN and Cr may show renal impairment. Hematuria and proteinuria in the urine should also be checked.

Some patients may require further investigations with CT or MRI depending on their symptoms and findings.

What is your opinion about the CT below?

Emergency Treatment Options

Initial Stabilization

Support C-A-B and stabilize the patient as needed. Cardiac monitoring, pulse oximetry, oxygen administration, and IV access required for all hypertensive emergency cases. Key precaution in the control of hypertensive situations is to maintain the balance of the benefits of immediate decreases in BP against the risk of a significant decrease in target organ perfusion. Therefore, IV agents are preferred because of their titration option. Do not ignore pain medication because some of them require effective pain control.

Medications in specific problems

Aortic dissection

The aim is to reducing shearing forces by decreasing the heart rate to 60-80 beats/min, and the systolic pressure to 140 mmHg and below, then to 120 whether the patient can tolerate. Organ perfusion should be monitored carefully. Na nitroprusside (0.3-0.5 μg/kg) is a potent agent, and the dose can be arisen by 0.5 μg/kg/min each time till the maintaining the expected effect on blood pressure. Along with Na nitroprusside, Esmolol (300 μg/kg IV bolus, then 50 μg/kg /min infusion) or labetalol (20-40 mg IV, then 20 mg IV on every ten mins, the maximum dose is 300 mg) helps to control heart rate. If beta blockers are contraindicated, verapamil (5-10 mg IV or diltiazem 0.25 mg/kg IV can be used.

Acute Hypertensive Pulmonary Edema

The blood pressure shouldn’t be decreased by more than 20-30%. The first choice is nitroglycerin (5-100 μg/min IV infusion). Start with 5 μg/min; then it can be increased up to 200 μg/min by increasing 10 μg on every five mins. Enalaprilat (0.625-1.25 mg IV in 5 mins every 4-6 hours) and nicardipine 5 mg/hr IV infusion, if no control in 15 mins 2.5 mg/hr dose can be added on every 15 mins).

Acute Coronary Syndrome

Maximum 20% of the blood pressure should be acutely decreased if the systolic blood pressure is higher than 160 mmHg. Nitroglycerin or oral metoprolol (50-100 mg/12 hrs or IV 5mg on every 5-15 mins up to 15 mg)

Acute Sympathetic Crises

Benzodiazepines are the initial treatment. Nitroglycerine can be considered if benzodiazepines are not effective. Phentolamine is another choice (5-15 mg IV).

Acute Renal Failure

The blood pressure decreased up to 20% if it is higher than 180/110 mmHg. Nicardipine, labetalol, or fenoldopam is recommended agents.

Intracerebral Hemorrhage

The mean arterial pressure (MAP) should be decreased to130 mmHg if the patient has increased intracranial pressure findings. If no suspicion of increased intracranial pressure, the MAP can be decreased to 110 mmHg or the systolic blood pressure to 150-160 mmHg. Esmolol and labetalol can be used.

Subarachnoidal Hemorrhage

The systolic blood pressure and the MAP should be lower than 160 mmHg and 130 mmHg, respectively. Esmolol and nicardipine can be used.

Ischemic Stroke

If the fibrinolytic will be used, the systolic blood pressure should be lower than 185/110 mmHg. If the patient will not take a fibrinolytic treatment, then it is important to maintain the BP lower than 220/120 mmHg. Nitroglycerin and nicardipine can be used.

Hypertensive Encephalopathy

The first agent is Na nitroprusside and followed by labetalol, nicardipine, fenoldopam. The systolic blood pressure shouldn’t be decreased by more than 25% of the total. A 160-170 mmHg systolic blood pressure is expected in first 2-3 hours.

Asymptomatic Situations

Oral antihypertensives (hydrochlorothiazides 25 mg/day, Metoprolol 25 mg/day, angiotensin receptor blockers, ACE inhibitors) should be given in the ED and prescribed to the patients whose systolic blood pressure is higher than 180-200 mmHg and the diastolic blood pressure higher than 110/120 mmHg.

Pediatric, Geriatric, and Pregnant Patients

In pregnant patients who have underlying hypertension may present with severe preeclampsia, stroke, pulmonary edema, fetal decompensation, etc. IV hydralazine and oral nifedipine are equally effective in pregnant patients. In the pediatric population, the hypertensive emergency with end-organ effects requires immediate, and gradual decreasing of the BP. Metoprolol is effective and safe in the pediatric population.

Disposition Decisions

Admission Criteria

All patients with hypertensive emergencies, signs of end-organ damage are admitted to the intensive care or high dependency care unit.

Discharge Criteria

Hypertensive urgencies (Absence of end-organ damage symptoms and findings, known to have hypertension, reversible causes, etc.)

Referral

Patients should refer to their primary care physician or hypertension clinic in 7 days.

References and Further Reading

Marik PE, Rivera R. Hypertensive emergencies: an update. Current Opinion in Critical Care 2011 Dec;17(6):569-80.
The Sixth Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC-VI). Arch Intern Med 1997; 157: 2413-46.
Backer HD, Decker L, Ackerson L: Reproducibility of increased blood pressure during an emergency department or urgent care visit. Ann Emerg Med 2003 Apr;41(4):507-12.
Ince H, Nienaber CA: Diagnosis and management of patients with aortic dissection. Heart 2007 Feb;93(2):266-70.
Nienaber CA, Eagle KA: Aortic dissection: new frontiers in diagnosis and management. Part II: Therapeutic management and follow-up. Circulation 2003 Aug 12;108(6):772-8.
Erbel R, Alfonso F, Boileau C, et al; Task Force on Aortic Dissection, European Society of Cardiology: Diagnosis and management of aortic dissection. Eur Heart J 2001 Sep;22(18):1642-81.
Abraham WT, Adams KF, Fonarow GC, et al: In-hospital mortality in patients with acute decompensated heart failure requiring intravenous vasoactive medications: an analysis from the Acute Decompensated Heart Failure National Registry (ADHERE). J Am Coll Cardiol 2005 Jul 5;46(1):57-64.
Costanzo MR, Johannes RS, Pine M, et al: The safety of intravenous diuretics alone versus diuretics plus parenteral vasoactive therapies in hospitalized patients with acutely decompensated heart failure: a propensity score and instrumental variable analysis using the Acutely Decompensated Heart Failure National Registry (ADHERE) database. Am Heart J 2007 Aug;154(2):267-77.
Hollander JE, Carter WC, Hoffman RS: Use of phentolamine for cocaine induced myocardial ischemia. N Engl J Med 1992 Jul 30;327(5):361.
10. Qureshi AI, Harris-Lane P, Kirmani JF, et al: Treatment of acute hypertension in patients with intracerebral hemorrhage using American Heart Association guidelines. Crit Care Med 2006 Jul;34(7):1975-80.
Qureshi AI, Bliwise DL, Bliwise NG, et al: Rate of 24-hour blood pressure decline and mortality after spontaneous intracerebral hemorrhage: a retrospective analysis with a random effects regression model. Crit Care Med 1999 Mar;27(3):480-5.
Naval NS, Stevens RD, Mirski MA, Bhardwaj A: Controversies in the management of aneurysmal subarachnoid hemorrhage. Crit Care Med 2006 Feb;34(2):511-24.
Adams HP Jr, del Zoppo G, Alberts MJ, et al: Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups. Stroke 2007 Sep;38(9):e96.
Gifford RW Jr. Management of hypertensive crises. JAMA 1991 Aug 14;266(6):829-35.