Hypertensive Crises Chief Residents 2016-2017 1

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

RN: he’s tachycardic to 118. Febrile to 101 RN: he’s tachycardic to 118. Febrile to 101. 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

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

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

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

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

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

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

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

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

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

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

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 100-110) 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

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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

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

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

Nitroprusside Recommended starting dose: 0.25 to 0.5 µg/kg/min max 8 - 10 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

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

Labetolol Dosage: 20 mg initially, followed by 20 - 80mg 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

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 0.5-1 mg/kg then maintenance dose 50-300 ug/kg/min

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

Nitroglycerin Initial dose: 5 µg/min, can be increased as necessary to 100 µg/min Onset of action 5 - 10 minutes Headache, reflex tachycardia, tachyphylaxis limit use 28

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 12 - 24 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

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

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

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

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 85-90 by 3 months 33

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

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 24- 48h in CVA Catecholamine excess (clonidine withdrawal, cocaine, pheo) avoid isolated beta blockade