1、Hypertensive EmergencyDaniel J.McFarlane M.D.Division of Hospital MedicineJanuary 2011OutlineEpidemiologyDefinitionsPathophysiologyDiagnosis and RecognitionTreatment Special CircumstancesEpidemiologyWhy should we care about hypertension?lOne of the most common chronic medical concerns in the USlAffe
2、cts 30%of the population age 20lRisk factor for Cardiovascular disease and mortalityCerebrovascular disease and mortalityEnd stage renal diseaseOther end organ damageDefinitionsHypertension(according to JNC VII)lNormal BP120/160/100l(Severe HTN180/110)Severe HTN is not a JNC VII defined entityDefini
3、tionsHypertensive Emergency lAcute,rapidly evolving end-organ damage associated with HTN(usu.DBP 120)lBP should be controlled within hours and requires admission to a critical care settingHypertensive Urgency lDBP 120 that requires control in BP over 24 to 48 hourslNo end organ damageMalignant Hyper
4、tension is no longer usedDefinitionsEnd-Organ Damage(%of cases)lCerebral infarction 24%lHypertensive encephalopathy16%lIntracranial hemorrhage4.5%lAcute aortic dissection2%lAcute coronary syndrome/myocardial infarction12%lPulmonary edema with respiratory failure22%lSevere eclampsia/HELLP syndrome2%l
5、Acute congestive heart failure14%lAcute renal failure9%PathophysiologyHypertensive EmergencylFailure of normal autoregulatory function lLeads to a sharp increase in systemic vascular resistancelEndovascular injury with arteriole necrosislIschemia,platelet deposition and release of vasoactive substan
6、ceslFurther loss of autoregulatory mechanismlExposes organs to increased pressure Diagnosis and RecognitionPresentationlAlways present with a new onset symptomTake a good historylHistory of HTN and previous controllMedications with dosage and compliancelIllicit drug use,OTC drugsDiagnosis and Recogn
7、itionPhysicallConfirm BP in more than one extremitylEnsure appropriate cuff sizelPulses in all extremitieslLung examlook for pulmonary edemalCardiacmurmurs or gallops,angina,EKGlRenalrenal artery bruit,hematurialNeurologicfocal deficits,HA,altered MSlFundoscopic examretinopathy,hemorrhageDiagnosis a
8、nd RecognitionLaboratory/Radiologic evaluationslBasic Metabolic Panel(BUN,Cr)lCBC with smear(hemolytic anemia)lUrinalysis(proteinuria,hematuria)lEKG to look for ischemialCXR to look for pulmonary edema if dyspnealHead CT for hemorrhage if HA or altered MSlMRI chest if unequal pulses and wide mediast
9、inum to look for aortic dissectionTreatmentHypertensive UrgencylNo end-organ damageNOT emergentlLook for reactive HTN and treat this firstDrugs,pain,anxiety,cocaine,withdrawallUse oral medications to lower BP gradually over 24-48 hours,likely 2 agents neededlMay be chronic,decrease BP slowly to avoi
10、d hypoperfusion of organslAvoid sublingual and IM administration due to unpredictable absorptionTreatmentHypertensive UrgencylAppropriate follow up for asymptomatic patients with no end-organ damageBP rangeAction Plan140-159/90-99Observe,confirm BP 2mos160-179/100-109Confirm,treat within 1mo180-209/
11、110-119Confirm,treat within 1wk210+/120+Confirm,treat now,close f/uMedicationsOral drug choices often based on comorbid conditionslHeart failureTH,BB,ACEI,ARB,ALDOlPost MIBB,ACEI,ALDOlHigh CVD riskTH,BB,ACEI,CCBlDiabetesTH,BB,ACEI,ARB,CCBlChronic Renal FailureACEI,ARBlRecurrent stroke preventionTH,A
12、CEIKEY:ACEI,angiotensin converting enzyme inhibitor;ALDO,aldosterone antagonist;ARB,angiotensin receptor blocker;BB,b blocker;CCB,calcium channel blocker;TH,thiazide.TreatmentHypertensive EmergencylAct QuicklylStart IV goal directed pharmacologic therapyContinuous infusion:short acting titratable me
13、dslInitiate critical care monitoringIntraortic BP monitoring may be necessarylStart SLOW:Limit initial lowering of BP to 20%below pretreatment levelDue to increased threshold of hypoperfusion of the organs from abnormal autoregulationlGoal:Lower DBP by 10-15%in 30-60 minlInitiate oral therapy and ti
14、trate IV medications downMedicationsIV,short acting,titratable.Arterial VasodilatorslHydralazine,fenoldepam,nicardipine,enalaprilVenous VasodilatorslNitroglycerineMixed Arterial and Venous VasodilatorslSodium nitroprussideNegative Inotrope/ChronotropelLabetolol(also vasodilates),EsmololAlpha blocker
15、s(inc.sympathetic activity)lPhentolamineMedicationsPreferred agents by usagelLabetololEsmololNicardipineFenoldopam(esp in pheochromocytoma)Preferred agents by end organ damagelPulmonary Edema(systolic)NicardipinelPulmonary Edema(diastolic)EsmolollAcute MILabetolol or EsmolollHypertensive Encephalopa
16、thyLabetolollAcute Aortic DissectionLabetolollEclampsiaLabetolol or NicardipinelAcute Renal FailureFenoldopamlSympathetic Crisis/CocaineVerapamil or Diltiazem Special CircumstancesAcute Aortic DissectionlStart IV meds STAT to lower pulsitile load and aortic stress to lessen the dissectionlVasodilato
17、rs alone may reflex tachycardialUse beta blocker AND vasodilator Esmolol and NitroprussidelSurgical evaluationType A all go to surgeryType B only if rupture/leak.Treat with aggressive BP controlSpecial CircumstancesStrokelNumber one cause of permanent disabilitylHTN is a protective physiologic effec
18、t to maintain blood flow to brainOne study showed better outcome if hypertensive upon presentation of strokelTreat HTN“rarely and cautiously”Lower BP 10-15%in first 24 hours(not 20%)lHemorrhagic strokeTreat if 200/110,but still with modest lowering of BP because still worse outcome with low BPSpecia
19、l CircumstancesEclampsialVasoconstricted and hemoconcentratedlVolume expand,magnesium sulfate,and aggressive BP control.lDelivery is only definitive treatmentlLabetolol or Nicardipine are drugs of choice.lHydralazine was first line but slow onset and unpredictable so may lead to hypotensionSpecial C
20、ircumstancesSympathetic CrisislCocaine use,rarely pheochromocytomalAVOID beta blockersleads to uninhibited alpha stimulation and increased BPlLabetolol has alpha and beta blockade,but experimental studies show poor outcomeslNicardipine,fenoldopam or verapamil(with a benzodiazepine)are drugs of choic
21、eReferencesHaas,A.and Marik,P.“Current Diagnosis and Management of Hypertensive Emergency.”Seminars in Dialysis.Vol 19,No 6.(2006)pp.502-512.Flanigan,J.and Vitberg,D.“Hypertensive Emergency and Severe Hypertension:What to Treat,Who to Treat,and How to Treat.”The Medical Clinics of North America.Vol 90(2006)pp.439-451.
