Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 1.. • 64 year old female you’ve diagnosed with acute bronchitis Hypertension in • Initial BP = 250/130 • On no meds Emergency Medicine • No history of hypertension • Feels fine except for cough MICHAEL JAY BRESLER, MD, FACEP • Ready for discharge: BP = 210/110 Clinical Professor Division of Emergency Medicine “Hey Doc, whadya want to give her?” Stanford University School of Medicine • 64 year old female you’ve diagnosed • 64 year old male complaining of severe with acute bronchitis chest pain for 3 hours • Initial BP = 250/130 • Initial BP = 230/120 • On no meds • EKG normal • No history of hypertension • Widened mediastinum on CXR • Feels fine except for cough • Repeat BP = 170/90 • Ready for discharge: BP = 250/140 • “Doc, they’re ready in CT.” “Hey Doc, whadya want to give her?” “Hey Doc, whadya want to give him?” Agenda for Our Discussion Questions to be addressed • General Considerations In the Emergency Department • Blood Pressure Readings in the ED • When should HBP be treated ? • Pathophysiology • When should HBP not be treated ? • Pharmacologic Treatment Modalities • When should outpatient therapy be • Specific Emergencies Requiring BP started? Reduction in the ED • What agents should we use? • Post ED Therapy • For what conditions? • Summary - Hypertension in the ED 1 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 2.. • I will use primarily generic names • But I will also include on the slides the brand names since these are most commonly used in the real world - I have no financial relationship where we practice • When there are several brand names I with any drug company will try to include them all • I have no idea which companies make which drugs What is Normal Blood Pressure ?? Prehypertension General 130-139/80-90 Considerations • Compared with normal BP – Double the risk for developing hypertension. • Lifestyle & diet intervention warranted Joint National Committee on Hypertension,2003 Incidence of Hypertension in U.S.A. Scope of the Problem • > 140/90 (HTN) • Normotensive people at age 55 have a – 27% of adults 90% lifetime risk of developing HTN (Ref: Vasan) • > 130/90 (pre HTN + HTN) • Between age 40-70, the risk of – 60% of adults! cardiovascular disease doubles for every – 88% > 60 years old (independent variables) – 40% ages 18-39 !! – 20 mm Hg systolic above 115 Wang Arch Intern Med 2004 – 10 mm Hg diastolic above 70 »Lewington Lancet 2002 2 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 3.. Should BP Rise with Age? BP and Gender • Estrogens protect NO !! • After menopause, women catch up with men and eventually surpass In societies with natural diet, less salt, and less obesity, more exercise the men – BP does not rise with age (in blood pressure that is….) • Diet is a particular problem - – We love our unhealthy diet! BP and Ethnicity High Blood Pressure Readings in • Incidence of HTN – 1.5 - 2 x more common in Blacks the Emergency Department • 1 in 3 African Americans • 1 in 4-5 Caucasian and Hispanic Americans • ? Asians • African Americans – HTN begins earlier – More end organ damage –ACEI’s & ARB’s less effective Is that reading real? Question • Asymptomatic E.D. patients with BP >140/90 – BP at home bid – > 1/2 continued >140/90 – Most of rest continued at pre-hypertensive level Are ED BP readings – Independent of pain or anxiety in E.D. accurate & reliable for » Tanabe Ann Emerg Med 2008 screening asymptomatic • E.D. patients with BP >140/90 followed in clinic patients for HTN? – 54% continued >140/90 » Cline Acad Emerg Med 2000 3 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 4.. ACEP Clinical Policy Question • Level B Recommendation –If SBP persistently > 140 or Do asymptomatic –If DPB persistently > 90 patients with elevated BP Refer for follow up of possible HTN benefit from rapid and BP management lowering of their BP? Ann Emerg Med. 2006;47:237-249 ACEP Clinical Policy • Level B Recommendation HBP in the ED – Initiating Tx in the ED is not necessary if F/U is available • Most useful terminology – Rapid lowering of BP is not necessary – Hypertensive Emergency and may be harmful – Hypertensive Urgency – When Tx is initiated, BP should be – Elevated Blood Pressure lowered gradually and should not be expected to be normalized during the ED visit Why is this the most useful classification? Ann Emerg Med. 2006;47:237-249 HBP in the ED Hypertensive Emergency • Hypertensive Emergency • By definition – Treated in ED with IV meds – Evidence of acute end organ damage • Hypertensive Urgency – Usually brain, heart, or kidney – May be treated in ED - oral meds OK • Definition implies that organ dysfunction – Usually give prescription is caused by acute HPB, rather than • Elevated Blood Pressure vice versa – Not treated in ED • Systolic usually > 220 – May or may not give prescription – We should refer for further evaluation • Diastolic usually > 130 4 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 5.. Hypertensive “Urgency” Hypertensive Urgency • Major elevation of BP • Treatment may be administered in the (roughly in range of >220/>120) but ED if BP remains very elevated – Without evidence of acute organ – Controversial failure – Trend toward not treating in the ED – No acute symptoms directly • Outpatient treatment should generally attributable to elevated BP be initiated, however • Basic studies may be indicated Diagnostic Studies in the ED • Incidental finding of moderate HBP – ED workup not necessarily indicated -> refer • If initiating outpatient treatment Pathophysiology – Basic studies in ED may be considered – CBC, lytes, renal, glucose, UA, EKG of Hypertension • If ED treatment required – Basic studies usually indicated • If hypertensive emergency - basic plus – Studies specific to disorder (CT, etc.) Regulation of Blood Pressure Inherent stiffness of arterial wall A Balance Between Cardiovascular risk factors lead to: • Replacement of elastin in arterial walls by collagen and fibrous tissue-> • Inherent stiffness of the arterial wall – Decreased compliance • Vasodilation – Increased resistance • Vasoconstriction • Endothelial dysfunction 5 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 6.. Pathophysiology Acute Regulation of BP BP --> Endothelial wall stretch/stress • Vasodilation – Beta-2 adrenergic innervation Endothelial Dysfunction – Nitric oxide c-AMP • Vasoconstriction Capillary permeability – Alpha-1 adrenergic innervation Depletion of NO – Circulating catecholamines Inflammation – Angiotensin II Renin-Angiotensin-Aldosterone Renin-Angiotensin-Aldosterone Angiotensin II Angiotensinogen • Powerful vasoconstrictor Renin • Release of aldosterone Angiotensin I • Inflammatory response • Hypertrophy of smooth muscle cells ACE • Decreased nitric oxide -> Angiotensin II further vasoconstriction Autoregulation and Hypertensive Crisis Organ-specific autoregulation Auto-Regulation and • Normally maintains capillary pressure Hypertensive Crisis & flow within an acceptable range – Increased systemic BP -> vasoconstriction – Decreased systemic BP -> vasodilation 6 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! Page 7.. Autoregulation of Cerebral Blood Flow Cerebral Autoregulation, Hypertension, and Excessive Correction • Cerebral arterial resistance varies directly Hypertensive with BP to maintain cerebral perfusion within Person acceptable limits • “Set point” rises with chronic HBP • Rapid ED reduction of BP may drop CPF below adequate level Normotensive • Lower BP gently, Person • And usually never < 110 diastolic – Except • with aortic dissection Mean Arterial Pressure Adapted from Elliott:Crit Care Clin 2001;17:435 Autoregulation and Hypertensive Crisis Pharmacologic Treatment Hypertensive crisis Modalities Autoregulation fails -> Endothelial dysfunction • Capillary permeability & edema • Inflammatory response • Prothrombotic response • Decreased nitric oxide Cell necrosis • Release of vasoconstrictors Pharmacologic Treatment Modalities • Parenteral Vasodilators • Beta Blockers • Calcium Channel Blockers • Angiotensin Converting Enzyme Parenteral Inhibitors • Angiotensin II Receptor Blockers Vasodilators • Direct Renin Inhibitors • Diuretics • Others 7 Doctor, Michael Jay Bresler, M.D The Patient’s Blood Pressure is Elevated! 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Parenteral Vasodilators Parenteral Vasodilators Nitroprusside (Nipride™, Nitropress™) Nitroprusside • Arterial > venodilator • Potential problems • Advantages – Unstable to UV light-must be wrapped – Most commonly used agent in EM – Orthostatic hypotension - keep supine – Metabolized to cyanide/thiocyanate – Extremely effective – Toxic at higher dose – Very short half-life • Potentially toxic to fetus • Are there better agents ?? – Tissue necrosis if extravasation – Increases intracranial pressure Parenteral Vasodilators Parenteral Vasodilators • Fenoldopam (Corlopam™) Nitroglycerin • Newer IV alternative to nitroprusside – Peripheral dopamine (DA-1) receptor agonist • Venodilation > arterial dilation – Rapid onset & offset of action – Good for CHF & angina – Improves renal function ? – Not a good drug for hypertensive crisis – Less chance of overshoot vs. nitroprusside – No thiocyanate toxicity or light sensitivity Beta blockers •ß1 blockade Beta – Lusitropic • (decreased cardiac contractility) Blockers – Decrease renin – Decrease norepinephrine 8 Doctor, Michael Jay Bresler, M.D The