Transcript Hypertensive Emergencies

Hypertensive Emergencies
Or How I Learned
to Stop Worrying
and Love Labetalol
Andrew T. Harris, MD
PGY3
August 4, 2015
Objectives
Define emergency vs urgency
 Overview of HTN urgency
 Brief review of classes of antihypertensives
 Review common scenarios and identify
appropriate treatments
 Common issues with diuretics

Take-home: sneak preview

Hypertensive Urgency  ORAL MEDS!!
◦ Rapid overcorrection can be very harmful
◦ Start low, go slow

IV Hydralazine  BAD
◦ Severe, unpredictable hypotension + reflex
tachycardia

Labetalol  GOOD
◦ Except in acute decompensated HF
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
Dilt gtt  NEVER in acute HFrEF
Always ask: “What is the EF?”
Problems with inpatient HTN
Difficult to determine true hypertensive
emergency
 Nurses keep paging me!!! It’s not an
emergency!!! AAAARGH!
 No accepted guidelines for management

Cochrane Review 2008:
Insufficient evidence to
support a single drug as
being more effective in
HTN emergency
Emergency vs Urgency

What differentiates emergency from
urgency?
Hypertensive Urgency

Best accepted definition
◦ Systolic BP > 180 OR
◦ Diastolic BP > 120
◦ No evidence of end organ damage (mild
headache does not count!)
Most commonly due to poorly controlled
chronic hypertension
 NOT an indication for hospital admission
 DO NOT use IV anti-hypertensives

Hypertensive Urgency

If admitted for other reasons, slowly lower BP with
oral medications over days
◦ No good evidence to guide timeframe or choice of
medication
◦ In general, lower systolic/MAP NMT 25% or to 160/100

Rapid correction below auto-regulatory range can
cause ischemia
◦ Cerebral (stroke)
◦ Coronary (MI)
◦ Renal (AKI)

Reasons to potentially lower over hours:
◦ Known aortic or cerebral aneurysm
◦ High risk of MI (known CAD, DMII)
Clinical Scenario #1
65 yo F with HTN admitted for PNA.
 You are on nightfloat. Nurse calls, BP is
180/110.Your signout says “NTD”
 What should you do?

Next Steps:
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Stall:
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What are the full vitals?
Is she symptomatic?
Can you recheck a manual BP?
What size cuff did you use?
Is she in pain?
Did she get her regularly scheduled meds?
I’m at a code, can I call you back?
OK, it’s still elevated, now what?
Hypertensive Urgency
Remember: start low, go slow
 Fully titrate before adding a second med

◦ Titrate to effect (or side effect)
Hypertensive Urgency
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Good medications
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Patient’s previous meds (nonadherence)
Amlodipine
ACE/ARB (check renal panel as outpt)
Labetalol (expensive outpatient med)
Diuretics
Bad Medications
◦ Anything IV
◦ Hydralazine, nifedipine (most of the time)

Clonidine
◦ It works, but watch out…..
◦ Severe rebound HTN, must be tapered
Hypertensive Emergency
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This is an indication for ICU admission!
Types of end organ damage
◦ Encephalopathy:
 Headache, altered mental status, visual disturbance
 Fundoscopic exam: look for papilledema
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Aortic or carotid dissection
MI/ACS/chest pain
Pulmonary edema with respiratory failure
Renal Failure
Pregnancy – ECLAMPSIA/HELLP
Microangiopathic Hemolytic Anemia

All things are poison and nothing is
without poison; only the dose makes a
thing not a poison.
-Paracelsus
Classes of Anti-Hypertensives
Beta Blockers
 Alpha Blockers
 ACE-I/ARBs
 Calcium Channel Blockers
 Vasodilators
 Diuretics

Beta Blockers

Labetalol: Alpha 1 + non-selective Beta
◦ Decrease HR w/o decreasing CO
◦ Good in most settings (except HFrEF)
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Esmolol: short acting Beta 1 antagonist
◦ Very quick onset, primarily rate control 
better with a vasodilator
◦ Comes with lots of fluid
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IV Metoprolol:
◦ Rate control, not anti-hypertensive
Calcium Channel Blockers
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Dihydropyridine
◦ Nicardipine
 SE: reflex tachycardia
◦ Clevidipine (mostly used in ED)
 Ultra-short onset (1 minute)
◦ Nifedipine
 AVOID – increased mortality

Non-dihydropyridine – negative inotropes
◦ Diltiazem – bad news in HFrEF
◦ Remember the Frank Starling curve
Frank-Starling Curve
Vasodilators

Nitroglycerin
◦ Primarily venodilator, reduces preload
◦ Arterial vasodilator at high doses, modest
afterload reduction
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Nitroprusside
◦ Arterial and venous dilator
◦ Cyanide toxicity (photodegradation) –
 Inhibits oxidative phosph

Hydralazine - BAD
◦ Prolonged, unpredictable drops in blood pressure
◦ Effect lasts up to 10 hours, best avoided
Other
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ACE-Inhibitors
◦ Enalaprilat (only IV form)
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Diuretics (more to come shortly)
◦ Furosemide
◦ Torsemide
◦ Bumetanide
Clinical Scenario #2
65 yo M, PMH of ischemic
cardiomyopathy (EF 35%), HTN, DMII
presents with acute SOB.
 T 98.8, BP 190/120, RR 25, PO2 sat 88%
 CXR – pulmonary edema
 What do you want to use?

Pulmonary Edema

Goals of therapy:
◦ Reduce afterload and preload
◦ Increase or maintain contractility
◦ Maintain stroke volume (permissive tachy)
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Low EF  avoid beta blockers/negative
inotropes
Nitroglycerin (reduces preload)
IV Diuretic (reduces preload and afterload)
Labetalol if preserved EF
NIPPV – reduces preload and afterload
Clinical Scenario #3
65 yo F, PMH of HTN, DMII, PAD
presents with chest pain at rest
 T 98.8, BP 190/120, RR 25, PO2 sat 94%
 ECG:
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◦ new TwI in I, II, aVL,V3-V6
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What do you want to use?
Acute Coronary Syndrome

Goals of therapy:
◦ Reduce Myocardial Oxygen Demand
◦ Reduce Heart Rate
◦ Reduce Afterload
Labetalol (or Esmolol)
 Nitroglycerin
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◦ Primarily anti-anginal
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ACE-Inhibitor if no contraindication
◦ Captopril short acting, easily titrated
Clinical Scenario #4
65 yo M, Marfan’s syndrome, HTN,
presents with severe CP radiating to back
 T 98.8, BP 190/120, RR 25, PO2 sat 94%
 CXR: widened mediastinum
 CT scan: descending aortic dissection
 What do you want to use?

Aortic Dissection
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Goals of therapy:
◦ Reduce shear stress
◦ Reduce Heart Rate
◦ Reduce Velocity of Blood Flow
Vasodilator alone will increase HR
 Vasodilator + beta blocker
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◦ Labetalol OR
◦ Nicardipine + Esmolol
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OK to aggressively reduce (<120/80)
Clinical Scenario #5
65 yo F with HTN, Carotid Stenosis
admitted for PNA.
 You are called by the nurse for new onset
L sided weakness
 T 98.8, BP 200/120, RR 18, PO2 sat 96%
 Besides calling a BAT, what medication
would you give?

CVA/Stroke
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HTN normal in acute stroke and
protective (first 24-48 hrs)
◦ Loss of autoregulation in the ischemic
penumbra

Ischemic Stroke
◦ Goal BP for thrombolytic therapy <180/105
◦ Labetalol or Nitroprusside if > 220/120
Hemorrhagic Stroke (depends on ICP)
 Ask your friendly neurologist for help
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Other Scenarios

Encephalopathy (goal: reduce ICP)
◦ Labetalol or Nicardipine
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Sympathetic Crisis
◦ Cocaine, Amphetamines, PCP (Urine Tox!!)
◦ Others: MAO inhibitor + tyramine, clonidine
withdrawal
◦ Avoid beta blockers – theoretical risk of
sympathetic crisis, unopposed alpha agonism
◦ Good options: Nicardipine or Verapamil +
benzo; Labetalol likely safe
A Word on Diuresis
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Threshold Dose
◦ Minimum effective dose
◦ Often 40 IV Lasix
◦ No response  double the dose
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Tolerance – hypertrophy of nephrons
◦ Add thiazide such as metolazone
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Conversions
◦ 40 Lasix = 20 Torsemide = 1 Bumex
◦ 40 Lasix PO = 20 Lasix IV
◦ Rule of thumb = give PO dose as IV
Diuretic Drips
Equivalent to bolus (DOSE trial)
 Good for quick titration in ICU
 Always bolus prior to starting drip or
adjusting the rate
 Furosemide: 40 IV then 10/hr
 Torsemide: 20 IV then 5/hr
 Bumetanide: 1 IV, then 0.5/hr
 Remember: higher doses in renal failure!

Take-home Points

Hypertensive Urgency  ORAL MEDS!!
◦ Rapid overcorrection can be very harmful
◦ Start low, go slow

IV Hydralazine  BAD
◦ Severe, unpredictable hypotension + reflex
tachycardia

Labetalol  GOOD
◦ Except in acute decompensated HF


Dilt gtt  NEVER in acute HFrEF
Always ask: “What is the EF?”