Hypertensive emergency: Difference between revisions

Revision as of 23:40, 1 March 2011

Diagnosis

End-organ damage 2/2 increased BP (generally >180/120, usually > 220/130)
Brain - Encephelopathy, seizure, ICH, ischemic stroke
Eyes - Retinal hemorrhage, exudate, papilledema
CV - MI, CHF/LV failure/pulm edema, aortic dissection
Renal - Acute failure, hematuria, proteinuria
Ancillary Tests
Chemistry - assess renal failure
UA - Assess renal failure, glomerulo nephritis, preeclampsia
Troponin
CXR - Evidenceo failure, dissection
ECG

Etiology

Idiopathic
Sympathomimetic drug use
Preeclampsia
Acute glomerulonephritis

Treatment

Goal: Lower diastolic pressure to 105mmHg within 2-6 hours
Maximum initial fall in BP should not exceed 25% of presenting value
Be careful of lowering BP in pts with CVA!

Drug Dose Mechanism Pros Cons Notes Nitroprusside 0.25-8µg/kg/min

(start at 0.25)

Arterial and veno-dilator 1. Very effective

2. Immediate onset/offset

1. Cyanide Toxicity

2. Coronary steal?

3. Incr HR

1. Avoid in liver/renal failure

2. Avoid with incr ICP

3. Avoid in pregnancy

Nitgroglycerin 5-100 µg/min Veno>arteriodilation 1. Rapid on/offset

2. Increases coronary flow

Causes Tachycardia Drug of choice in pts w/ cardiac ischemia,

LV dysfunction, and pulm edema

Labetalol 20-80mg IV bolus q10min OR

0.5-2mg/min IV

Beta>alpha blocker 1. No change in HR, cerebral flow

2. Rapid onset

Avoid in COPD, CHF

heart block

1. Consider in ACS

2. Consider in ischemic CVA

Esmolol 250-500 µg/kg/min;

may repeat bolus after

5min or incr to 300µg/min

Beta selective 1. Rapid on/offset Avoid in COPD, CHF

bradycardia

Consider in ACS

Nicardipine 5-15mg/h Decreases PVR Good for intracranial pathology Slower onset/offset Avoid in CHF, ACS Hydralazine 5-10mg IV bolus, max dose 20mg OR 0.5-1mg/min IV infusion Arteriolar vasodilator Rarely causes hypotension Avoid in CAD Primarily used in pregancy Phentolamine 5-10mg IV bolus q5-15min OR

0.2-5mg/min IV infusion

Alpha blocker Used for catecholamine-induced HTN Enalapril 1.25mg over 5min q6hr Decreases HR, SV, systemic arterial pressure Does not impair cerebral flow Variable response 1. Used in pts at risk for cerebral hypotension, CHF

2. Avoid in pregnancy

Disease Specific

HTN Encephalopathy

    Controlled redxn of BP over 1h; never < 110 diastolic

         Labetolol, nicardipine, fenoldopam; nitroprusside of diastolic > 140

Stroke

    10-15% reduction of MAP; diastolic not < 110

    lower to 185/110 in ischemic stroke to meet t-PA criteria

         Labetolol, nicardipine, nitroprusside as above

Acute Aortic Dissection

    Rapid redxn of BP, systolic bp 100-120; HR 60-80 within 20mins

    Prevent reflex tachycardia

         Nitroprusside, fenoldopam, nicardipine with metoprolol or esmolol; labetolol alone

ACS and Pulmonary Edema

    Nitroglycerin

Eslampsia/Pre-eclampsia

    Labetolol, nicardipine or IV hydralazine

    Magnesium

Cocaine and Amphetamine Toxicitiy

    BDZs

    Mixed alpha + B blockade: phentolamine or nitroprusside plus beta blocker

Pheochromocytoma

    Phentolamine or nitroprusside plus beta blocker

ARF

    Fenoldopam, nicardipine; nitroprusside risk cyanide toxicity (renal metabolism)

Source

Adapted from Bessen, Bresler (ACEP '09), UpToDate

Authors:

@@ Line 2: / Line 2: @@
-Need for acute BP reduction d/t end-organ dysfunction
+* End-organ damage 2/2 increased BP (generally >180/120, usually > 220/130)
+* Brain - Encephelopathy, seizure, ICH, ischemic stroke
-Generally need ≥180/120 mmHg, but usually >220/130
+* Eyes - Retinal hemorrhage, exudate, papilledema
+* CV - MI, CHF/LV failure/pulm edema, aortic dissection
+* Renal - Acute failure, hematuria, proteinuria
+* Ancillary Tests
-BRAIN- HTN encephelopathy, seizure, ICH, ischemic stroke
+* Chemistry - assess renal failure
+* UA - Assess renal failure, glomerulo nephritis, preeclampsia
-HEART- AMI, CHF/LV failure/pulm edema, Aortic Dissection
+* Troponin
+* CXR - Evidenceo failure, dissection
-EYES- Retinal hemorrhages, exudates, or papilledema
+* ECG
-KIDNEYS- Acute Renal Failure
-(Pre)Eclampsia
-Catecholamine-induced HTN
-CAUTION: Ischemic stroke and tPA candidates
-==Treatment ==
-GOAL: Reduction of MAP by 10-15% in first 1-2 hrs
-(no more than 25%, except in dissection)
-MAP= (2/3)DBP +(1/3)SBP
-DRUGSNitroprusside
-mech - arteriolar and venous dilation
-pros  - very effective rapid on/offset
-cons  - cyanide toxicity, caution in renal insufficiency
-         - potential hypotension and end-organ hypoperfusion
-         -  tissue necrosis if extravasation
-         - increases intracranial pressure
-dose - 0.5-8 mcg/kg/min
-Nitroglycerin
+==Etiology==
-mech - venodilation at low doses, arteiolar at high doses
-pros - usually readily available in the ED
-        - rapid on/offset
-        - improves coronary collateral flow
-        - good for CHF, angina; bad for HTN crisis
-cons- tachycardia, tolerance
-dose - 10-250 mcg/min
+* Idiopathic
+* Sympathomimetic drug use
+* Preeclampsia
+* Acute glomerulonephritis
-Labetalol
+Treatment
-mech- alpha/beta blockers (beta>alpha), vasoldilation
-pros- no change in HR
-cons- not for copd, those with beta-blocker intolerance
-dose - if bolused, 20mg, 40-80mg q10min (max 300mg)
-mg/min infusion
+* Goal: Lower diastolic pressure to 105mmHg within 2-6 hours
+* Maximum initial fall in BP should not exceed 25% of presenting value
+* Be careful of lowering BP in pts with CVA!
-Hydralazine
+Drug 	Dose 	Mechanism	Pros	Cons 	Notes
+Nitroprusside 	0.25-8µg/kg/min
-mech- arteriolar dilator
+(start at 0.25)
-pros- obs like it for eclampsia
+	Arterial and veno-dilator	1. Very effective
-cons- reflex tachycardia, unpredictable bp effect, sometimes takes hours for effect
+. Immediate onset/offset
-dose - 10mg q20min
+. Cyanide Toxicity
-.5-1 mg/min IV infusion
+. Coronary steal?
+. Incr HR
-Nicardapine
+. Avoid in liver/renal failure
-mech- CCB (dihydropyridine); decreased PVR > cardiac
+. Avoid with incr ICP
-pros- rapid onset, neurosrugeons like it
+. Avoid in pregnancy
-cons- slower offset than NTP or NTG
+Nitgroglycerin 	5-100 µg/min 	Veno>arteriodilation 	1. Rapid on/offset
-dose - 5 mg/hr, max 15mg/hr
+.  Increases coronary flow
+	Causes Tachycardia 	Drug of choice in pts w/ cardiac ischemia,
-ACE-i (enalaprilat)
+LV dysfunction, and pulm edema
-no well studied
+Labetalol	20-80mg IV bolus q10min OR
-dose - 1.25 mg q6 hr
+.5-2mg/min IV
+	Beta>alpha blocker	1. No change in HR, cerebral flow
-Fenlodopam
+. Rapid onset
-mech- peripheral dopamine agonist--->ateriolar dilation
+	Avoid in COPD, CHF
-pros- rapid on/offset, renal insufficiency
+heart block
-cons- $$$
+. Consider in ACS
-dose - 0.1 µg/kg/min
+. Consider in ischemic CVA
-Phentolamine
+Esmolol	250-500 µg/kg/min;
-mech- alpha blocker
+may repeat bolus after
-pros- esp, pheochromcytoma (catecholamine-induced)
+min or incr to 300µg/min
-cons- hard to find, waiting for pharmacy
+	Beta selective	1. Rapid on/offset 	Avoid in COPD, CHF
-dose - 5 to 10 mg every 5 to 15 minutes
+bradycardia
-.2-5 mg/min IV infusion
+	Consider in ACS
+Nicardipine   	5-15mg/h	Decreases PVR	Good for intracranial pathology 	Slower onset/offset 	Avoid in CHF, ACS
+Hydralazine 	5-10mg IV bolus, max dose 20mg OR 0.5-1mg/min IV infusion	Arteriolar vasodilator 	Rarely causes hypotension 	Avoid in CAD	Primarily used in pregancy
+Phentolamine 	5-10mg IV bolus q5-15min OR
-Esmolol
+.2-5mg/min IV infusion
-mech- beta blocker
+	Alpha blocker 	 	 	Used for catecholamine-induced HTN
+Enalapril	1.25mg over 5min q6hr	Decreases HR, SV, systemic arterial pressure	Does not impair cerebral flow	Variable response	1. Used in pts at risk for cerebral hypotension, CHF
-pros- ultra short-acting, dissection
+. Avoid in pregnancy
-cons- not for copd, those with beta-blocker intolerance
-dose - Loading dose: 250-500 mcg/kg infused over 1 min
-Maintenance infusion: 50 mcg/kg/min over 4 min
-==Organ Specific==
+Disease Specific
 HTN Encephalopathy
@@ Line 226: / Line 170: @@
+Source
-==Source ==
-Adapted from Bessen, Bresler (ACEP '09)
+Adapted from Bessen, Bresler (ACEP '09), UpToDate