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Hypertensive Emergencies. Jason R. Frank MD MA(Ed) FRCPC Department of Emergency Medicine. HTN – What’s the Big Deal?. KEY objectives: Differentiate malignant HTN from secondary conditions Conduct initial HTN lowering treatment. OBJECTIVES:
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Hypertensive Emergencies Jason R. Frank MD MA(Ed) FRCPC Department of Emergency Medicine
KEY objectives: Differentiate malignant HTN from secondary conditions Conduct initial HTN lowering treatment OBJECTIVES: Differentiate non-localizing neurologic symptoms Determine presence of other hypertensive emergencies Interpret clinical & lab findings Conduct an effective management plan, including specific Rx MCC OBJECTIVES – HTN EM
Case 1 • 50 woman sent in by community MD & pharmacist for “HTN emergency” • Pharmacy BP = 190/90 • Extremely worried, otherwise well • Q: What is the clinical definition of HTN?
Case 2 • 65 male drove in from cottage • Feeling unwell • Flagged at triage with BP 200/100 • Forgot BP meds at home…missed 3 days • Q: What is a “hypertensive urgency”?
Case 3 • 72 male with chronic HTN, PAFib, and arthritis. • Referred to CDU with elev BP “for observation”. • 180/115 at rest • Progressive SOB over the am. • Q: What is the definition of a “hypertensive emergency”?
Case 4 • 45 CEO of an IT firm • Presents with cp, SOB, intense anxiety • Sweating, tacky, BP 200/120 • Admits to cocaine • Q: Management?
Case 5 • 33 F 1 week post-partum • Epigastric pain • Seizure • BP 160/95, P90, T37.2 • Q: Dx? Management?
Case 6 • 60 M presents with tearing RSCP • Rad to back • Assoc with L headache and R leg weakness • BP 190/100, P 95 • Q. Management?
This Session: HTN EM • Define HTN • Classify HTN • Provide a DDx for the acutely hypertensive patient, including 2ndary causes • Describe the findings of a patient with a HTN emergency • Describe high-utility tests for HTN EM • Describe the management of each of the categories of HTN • Describe at least 2 controversies in the management of HTN EM
HYPERTENSION Standard Definition • Based on 3 measurements, each 1 wk apart > 140 systolic > 90 diastolic • Most important #: Diastolic • MAP = 1/3 Systolic, 2/3 Diastolic
Define HTN? Joint National Commission VIVII 2003 “Pre-HTN”
Primary or Secondary • Majority (90-95%) essential HTN • Of Secondary: ½ have a potentially curable cause
HTN in the Population vs the ED? • Primary HTN • Chronic • “Essential” • >95% • >25% of NA pop’n • 50% adhere to Rx • 75% not optimal • More un-Dx • Pre-HTN
Thinking about a HTN Definitions: • Pre-HTN……………........ • Primary chronic…………. • Transient ……………….. • Secondary………………. • “Tertiary” ...……………… • Malignant…………......... • Also: accelerated, severe, crisis, etc • 130-139/80-89 • >140/90 • white coat, anxiety, pain, etc • Pathologic organ cause • Iatrogenic, ingestion, withdrawal, etc • Bad (enceph & retinal)
HTN in the ED – a Taxonomy • Transient HTN • Chronic HTN • HTN Urgency • HTN Emergency • HTN-associated Crisis
Transient HTN - Examples • Anxiety • Pain • EtOH-withdrawal • White-coat
HTN “Urgency” • HTN “threatening” end organ damage • “End organs at risk” • Various definitions: DBP>110, DBP>115, DBP>120 • Goal: lower BP over hours; rarely requires treatment • Concern: bogus category, may lead to harm (eg CVAs) -see Gallagher 2003
Malignant Hypertension Severe HTN & Evidence of acute end-organ damage • Diastolic BP usually > 130 mm Hg or MAP > 160 • Relative rise much more important than # • Affects 1% of hypertensive patients
MAP is What Matters: • At normal resting heart rates MAP can be approximated using the more easily measured systolic and diastolic pressures, SP and DP • or equivalently • or equivalently • where PP is the pulse pressure: SP − DP -Wikipedia
“The Delta Diastolic Threatens Death” The change in DBP accounts for most of the change in MAP “∆ DBP is where it is at” (for the ED setting)
Hypertensive Emergency? Volhard & Fahr, 1914
HTN Emergency Acute elevation in MAP causing end organ damage: • ARF • CHF, ACS • Encephalopathy (>160 MAP) • CVA, ICH • Hemolysis • Retinal • All have DBP >120 …Mortality ~90% historically
HTN Emergency – Organ Incidence? Acute elevation in MAP causing end organ damage: • CVA (24.5%) • CHF (22.5%) • Encephalopathy (16.3%) • ACS (12%) • ICH (4.5%) • ARF (?) • Hemolysis (?) • Retinal (?) From Zampaglione, 1996
HTN Emergency Pathophysiology: • Failure of autoreg • Rapid rise in SVR • Endothelial injury • Arteriolar necrosis • Ischemia • …Cascade
Increased CO RF with fluid overload Acute renal disease Hyperaldosteronism Cushing’s syndrome Coarctation of the Aorta Increased vascular resistance Renal Artery Stenosis Pheochromocytoma Drugs Cerebrovascular (CVA, ICH, SAH) Secondary HTN
Renal Artery Stenosis • most common treatable cause (1-5%) • compromised renal perfusion => activation of RAA • 2 pt groups: • Elderly with atherosclerotic disease • Young females with fibromuscular dysplasia • Clinical: abdo bruit (40-80%), retinopathy, HTN resistant to Rx, hypoK
Aldosteronism • Uncommon but treatable • Na retention, volume expansion, increased CO • Hypernatremia & Hypokalemia typical • Primary: Adrenal adenoma, hyperplasia • Secondary: Cushing’s, CAH, exogenous mineralcorticoids
Pheochromocytoma • Tumour, usually in adrenal medulla • Produces xs catecholamines (epi, NE) • Paroxysmal HTN…difficult to recognize • Episodic HTN, HA, palpitations, diaphoresis, anxiety…not a panic attack! • Easy to diagnose: elevated urinary catecholamines, metanephrines, vandillylmandelic acid
Coarctation of the Aorta • Rare but early surgical intervention can improve prognosis • Clinical triad: • upper extremity HTN • systolic murmur over back • delayed femoral pulses
Drugs • Cocaine, amphetamines • ETOH withdrawal • Withdrawal from clonidine, beta blocker • MAOI + tyramine containing foods or certain Rx (meperidine, TCA, ephedrine) • Tyramine causes release of NE • Usually rapidly destroyed by MAO
Secondary HTN • Neuro: • Autonomic dysfunction (eg GBS, cord injuries) • CNS insult (HI, ICH) • Renal: • Renovascular stenosis • Renal disease (eg GN, Chronic pyelo) • Endocrine: • Pituitary tumours / ectopic ACTH • Pheochromocytoma; renin tumours; Hyperaldosteronism (egCushings) • Hyper & hypo thyroid & thyroid storm • Vascular: • Coarctation of the Ao • Vasculitis; Collagen-vascular (eg Scleroderma) • Pre-/Eclampsia • Sleep apnea
Iatrogenic / Lifestyle HTN (aka “tertiary”) Too Much: Too Little: Clonidine withdrawal Anti-HTN withdrawal EtOH withdrawal • Tyramine-MAOI • Glucocorticoids • Thyroxine • Fluid overload • NSAIDS • Sympathomimetics
HTN – associated Crisis • HTN is a critical issue relating to an emergency Dx: • Aortic Dissection • Pre/Eclampsia • ICH • CVA • Cocaine
HTN in the ED – a Taxonomy 2 • Pre-HTN • Chronic HTN • Transient HTN • HTN Emergency • HTN-associated Crisis • 1’, 2’, 3’
Case 1 • 50 yo woman sent in by community MD & pharmacist for “HTN emergency” • Pharmacy BP = 190/90 • Extremely worried, otherwise well
Case 2 • 65 male drove in from cottage • Feeling unwell • Flagged at triage with BP 200/100 • Forgot BP meds at home…missed 3 days
Case 3 • 72 yo male with chronic HTN, PAFib, and arthritis. • Referred to CDU with elev BP “for observation”. • 180/115 at rest • Progressive SOB over the am.
DDx for the ED Hypertensive Patient • Transient: pain, anxiety, sympathetic outflow • Chronic essential: poorly controlled • Chronic secondary: renovasc, pyelo, GN, pituitary, thyroid • Iatrogenic: fluid overload, pressors • OD/Ingestion: tyramine-MAOI, cocaine, amphetamines, • HTN-associated crises: Ao dissection, PIH, ICH, CVA, etc • HTN emergencies: CNS, ACS, CHF, retinal, RBCs
Assessing the HTN Patient in the ED: • Hx HTN & Tx • Rx use • PMHx • Symptoms of end-organ damage • Pain • Confirm BP • Good BP reading • End-organ damage • Heart sounds • Pulses • Fundoscopy
Testing for ED HTN: • CBC, 7 • EKG • CXR • Urine • CT head prn r/o HTN emergency
HTN Management by Category: • Pre-HTN……………… • Chronic HTN…………. • Transient HTN……….. • HTN Emergency…...... • HTN-associated Crisis. • Advise • Advise, note, po Rx prn • Assess, observe, benzo prn • Assess, lower 20% ~1 hour • Dx-specific tx
Key Agents for Canadian EM Practice: • Metoprolol • Labetolol • Nitroglycerine Also: • Nitroprusside • Magnesium • Esmolol • Phentolamine • Ramipril • 25-100 po; 5 – 20 IV • 20 mg bolus IV to max 300 mg • 5-100 ug/min • 0.25-10 ug/kg/min [Lancet, 1949] • 2-6g, then 2g/hr infusion • Load 500ug/kg/ 1min, then 50ug/kg/min, titrate • 5-10 mg/min • 2.5-5 mg po