1. Hypertensive Crises
Chief Residents 1

2. Your first night on cross cover:
Call at 8:02pm: Patient admitted for etoh withdrawal in SBMU – Found to have BP 180/110.
What do you want to know?
Other vitals (tachy, fever)? Level of agitation – CIWA score? When was his last dose of benzos what did he get? Able to tolerate PO or IV only? Cumulative dose of benzos over the last few hours? 2

3. RN: he’s tachycardic to 118. Febrile to 101
RN: he’s tachycardic to Febrile to Has been getting ativan IV every hour 1mg for the last several hours. He is extremely agitated.
What now?
Go see the patient! Is he going into DTs (mortality 5%)? Try longer acting benzo, repeat vitals, make sure this isn’t new fever, if requiring very frequent dosing may need to call ICU screen. 3

4. Call at 0200: 90 y/o F admitted for AKI, found to have BP 180/110.
What do you want to know?

5. RN: She’s hypoxic to 88% and RR 30. Tachycardic to 112
RN: She’s hypoxic to 88% and RR 30. Tachycardic to It seems like she’s having trouble breathing.
She’s been getting 75 cc/hr for the last 3 days.
What do you do now?

7. Call at 0339:
- 62 y/o M admitted last evening for hypertensive urgency associated with headache. All other studies normal. Found to have BP of 220/125 and he’s difficult to arouse, with left-sided weakness. 7

8. What else do you want to know?
How will you manage his blood pressure?

9. Urgency vs. Emergency
HTN Urgency refers to asymptomatic Severe HTN (>180/120)
HTN Emergency refers to Severe HTN with evidence of end organ damage
Retinal Hemorrhages/Exudates
Papilledema
Acute Kidney Injury – malignant nephrosclerosis
Intracerebral/SAH/CVA
Hypertensive Encephalopathy
HA, N/V, Confusion, Seizures, Coma
Pulmonary edema/Cardiac ischemia/Aortic dissection 9

10. Causes of hypertension in the hospitalized patient
Wrong sized BP cuff (too small will falsely elevate bp)
Agitation / Delirium
Pain
Volume overload
New event (CVA, hypoxia, CHF, PE)
Drug withdrawal (beta blockers, clonidine, etoh)
Drug intoxication (cocaine, polysubs abuse) 10

11. Medications That May Precipitate Hypertensive Emergencies / Urgencies
Oral contraceptives
Monoamine oxidase inhibitors
Tricyclic antidepressants
Steroids
NSAIDS
Nasal decongestants
Appetite suppressants

12. HTN Urgency: Treatment
For those patients without End-Organ Damage, Treatment consists of:
BP lowering with the oral agent the patient was taking previously
For untreated patients use thiazide, ACEI or Ca++ channel blocker, likely need combo
Goal is MAP reduction of 25% in first 4-6 hours
sooner if high risk of imminent cardiac events
In those cases, consider captopril, nifedipine (NOT SL), clonidine, furosimde
Requires close (q1-2 days) follow up, but does not always require admission
Consider admission for patients without adequate outpatient follow up 12

13. Non-emergent BP lowering
If patient on BP meds consider extra-doses before starting new meds
amlodipine, PO labetalol, nitro paste, diuretics good for acute BP lowering
Consider underlying conditions when starting new meds
i.e. DM, CKD etc

14. HTN Emergency Pathophysiology
abrupt increase in systemic vascular resistance (many possible triggers)
increase in BP generates endothelial injury leading to increased permeability, activation of the coagulation cascade and platelets, and deposition of fibrin.
fibrinoid necrosis of the arterioles ensue
RAS activation- leading to further vasoconstriction and the production of proinflammatory cytokines such as interleukin-6
pressure natriuresis leads to volume depletion & further stimulates the release of vasoconstrictors from the kidney
culminates in end-organ hypoperfusion

15. HTN Emergency: Treatment
Use parenteral drugs with rapid onset of action, rapidly titratable
Initially decrease the BP by no more than 25% (usual goal diastolic )
Arterial line often necessary
Then decrease to < 140/90 over 2-3 months with oral therapy
Exceptions: ischemic stroke and aortic dissection
Why do we do this? 15

17. 17

18. 18

19. 19

20. Hypertensive Emergency
Can use a number of parenteral agents:
Nicardipine
Nitroprusside
Esmolol
Nitroglycerin
Labetolol
Enalaprilat
Avoid sublingual or IM routes, variable time to onset and absorption
Avoid sl nifedipine. Unpredictable drop in bp.
Peripheral vasodilation and steal phenomenon in certain vascular beds→MI, CVA 20

21. Nicardipine Calcium Channel Blocker Arteriolar Vasodilator
Initially given IV-starting dose 2-5mg/hr, maximum dose 15mg/hr
Use in intracranial hemorrhage to reduce vasospasm
Preserves cerebral and coronary blood flow
Safe in MI, CHF, CVA 21

22. Nitroprusside cyanide liver thiocyanate Excretion in urine kidney
Dilates both arterioles & veins
Extremely effective
Acts within seconds, effect disappears within minutes
Major limitation is metabolism to cyanide, or thiocyanate toxicity
Must have intact liver & kidneys
cyanide
liver
thiocyanate
Excretion in urine
kidney
thiosulfate 22

23. Nitroprusside
Recommended starting dose: to 0.5 µg/kg/min max µg/kg/min (no more than 10 minutes)
Dose dependent cyanide / thiocyanate toxicity:
altered mental status
lactic acidosis
Sodium thiosulfate infusion can be given as “antidote”
May increase ICP
Avoid in HTN encephalopathy or CVA
Can cause coronary steal – avoid in ischemia.
Increased mortality in MI 23

24. Labetolol Combined beta-adrenergic and alpha-adrenergic blocker
Rapid onset of action (< 5 min)
Safe in patients with CAD
Caution with COPD, asthma, AV block, decompensated heart failure
Safe to use in pregnancy 24

25. Labetolol
Dosage:
20 mg initially, followed by mg every 10 minutes to a total of 300 mg
Infusion rate: 0.5 to 2 mg/min
Adverse effects:
vomiting, scalp tingling
burning in throat, dizziness
heart block 25

26. Esmolol Cardioselective beta blocker Immediate onset Short acting
Does not depend on renal or hepatic metabolism
Use for aortic dissection and catecholamine excess (along with alpha blocker)
Initial bolus mg/kg then maintenance dose ug/kg/min

27. Nitroglycerin venodilation & at high doses arteriolar dilation
Most useful in:
pts with coronary ischemia
pts. with HTN following CABG
in the setting of CHF 27

28. Nitroglycerin Initial dose:
5 µg/min, can be increased as necessary to 100 µg/min
Onset of action
minutes
Headache, reflex tachycardia, tachyphylaxis limit use 28

29. Enalapril Long acting IV preparation of enalapril
initial dose 1.25 mg, max 5 mg q6h
Onset of action 15 min, peak effect may not be seen for 4h, duration of action h
Useful in CHF
Response is variable and not predictable
avoid in the setting of renal failure – contraindicated if bilateral renal artery stenosis
May cause precipitous drop in BP in setting hypovolemia 29

30. Hydralazine direct-acting arterial vasodilator
Onset 5 to 20 min effects last up to 12 h
Not easily titratable due to variable hypotensive effect
Contraindicated in coronary ischemia
May increase ICP in patients already predisposed to elevated ICP
Reflex tachycardia – give with beta blocker
Generally AVOID in hypertensive crises

31. Diuretics Useful in CHF, volume overload states, post-op
Generally avoid in HTN crisis due to volume depleted state (pressure natriuresis)

32. Pregnancy and Hypertension
Safe medications:
HCTZ, labetalol, hydralazine, methyldopa (weak anti-HTN), nifedipine (limited data)
Contraindicated:
ACE- Inhibitors

33. Long term
Most patients with a history of Malignant HTN have some residual chronic vascular damage
continued risk for coronary, cerebrovascular, and renal disease
Slow outpatient oral BP management should focus on lowering diastolic BP to by 3 months 33

34. Acute pulmonary edema/diastolic dysfunction
Esmolol, metoprolol, labetalol, or verapamil in combination with low-dose nitroglycerin and a loop diuretic
Acute myocardial ischemia
Labetalol or esmolol in combination with nitroglycerin
Hypertensive encephalopathy
Nicardipine, labetalol, or fenoldopam
Acute aortic dissection
Labetalol or combination of nicardipine and esmolol or combination of nitroprusside with either esmolol or IV metoprolol
Pre-eclampsia, eclampsia
Labetalol or nicardipine
Acute renal failure/microangiopathic anemia
Nicardipine or fenoldopam
Sympathetic crisis/cocaine overdose
Verapamil, diltiazem, or nicardipine in combination with a benzodiazepine
APH
Esmolol, nicardipine, or labetalol
Acute ischemic stroke/intracerebral bleed

35. Pearls Nicardipine almost always a good choice for HTN emergency
Never start a vasodilator before established beta blockade in aortic dissection
Remember permissive HTN (unless > 220/120) for first h in CVA
Catecholamine excess (clonidine withdrawal, cocaine, pheo) avoid isolated beta blockade