高血压危象(英文版)-课件.ppt

1、高血压危象（英文版）PPTlHypertension is an increasingly important medical and public health issue.lThe prevalence of hypertension increases with advancing age to the point where more than half of people aged 60 to 69 years old and approximately three-fourths of those aged 70 years and older are affectedlData

2、from observational studies involving more than 1 million individuals have indicated that death from both ischemic heart disease and stroke increases progressively and linearly from BP levelsBlood pressure measurementPosition statement:Ambulatory and home BP measurementPatient characteristics associa

3、ted with resistant hypertensionSecondary causes of resistant hypertensionMedication that can interfere with blood pressure controlConditions favouring use of some antihypertensive drugs versus others Compelling and possible contraindications to use of antihypertensive drugs lDefinitions-Is This:A Cr

4、isis?An Emergency?An Urgency?lClinical PresentationslTreatmentsOther TerminologylSeverely elevated BP(JNC VII)lDefined as BP 180/120l“accelerated HPT”term used to describe individuals with chronic hypertension with associated group 3 Keith-Wagener-Baker retinopathyl“malignant HPT”describe those indi

5、viduals with group 4 KWB retinopathy changes+papilledemalHypertensive Emergency1-2 hoursRapid/progressive end organ damagelHypertensive Urgency.24-48 hrsInc.BP without evidence of end organ damagelUncontrolled Hypertension.1 weekDo not require acute interventionShayne PH-Ann Emerg Med-01-APR-2003;41

6、(4):513-29lHypertensive encephalopathylIntracerebral bleedlAcute MIlAcute CHF with pulm edemalUnstable anginalAortic dissectionlEclampsiaTx:parenteral agentBP 180/120 with evidence of target organ dysfunctionCerebral InfarctIntracerebral HemorrhageCerebral EdemaHypertensive EncephalopathyCerebral Pe

7、rfrelCerebral blood flow a function of CPPlAutoreg.Fails at 25%of MAPl ICP CPP Vulnerable to MAPCBF=blood flow;CPP=cerebral perfusion pressure;ICP=intracranial pressure;MAP=mean arterial pressure;TCA=total circulatory arrest.Hypertensive EncephalopathyPathophysiology:-Loss of Cerebral Autoregulation

8、 of blood flow resulting in hyperperfusion of the brain,loss of integrity of the blood brain barrier,and vascular necrosis.-Loss of Autoregulation occurs at a constant cerebral blood flow of above MAP 150 to 160 mmHg.-Acute Onset-ReversibleHypertensive EncephalopathySymptoms:Headache,Nausea/Vomiting

9、,Lethargy,Confusion,Lateralizing neurological symptoms that are not often in an anatomical distribution.Signs:Papilledema,Retinal Hemorrhages Decreased level of consciousness,Coma Focal neurological findingsHypertensive encephalopathylClinical manifestation of cerebral edema and microhemorrhages see

10、n with dysfunction of cerebral autoregulationlDefined as an acute organic brain syndrome or delirium in the setting of severe hypertensionHPT EncephalopathylNot adequately treated cerebral heamorrhage,coma and death.lBUT with proper treatment completely reversiblelClinical diagnoses(exclusion)Manage

11、ment of Hypertensive EncephalopathylReduce Mean Arterial Pressure(MAP)by 20 to 25%(T.397)and do not exceed this within first 30 to 60 min.lRosen recommends reduction of 30 to 40%(R.1759)lMAP=1/3(SBP-DBP)+DBPlTreatment Reduces vasospasm that occurs at these high pressureslAvoid excessive BP reduction

12、 to prevent hypoperfusion of the brain and further cerebral ischemialCerebral overperfusionMAP overwhelms autoregulationVasodilation and Inc.Perm.Cerebral EdemalHemorrhage,Coma,DeathlTx:Nipride,Fenoldopam,Labatalol,NicardipinelHypertensive Vascular DiseaselArteriovenous Anomalies(AVM)lArterial Aneur

13、ysmslTumorslTraumaHemorrhagic CVA ManagementlHemorrhagic CVAs commonly results in a profound reactive rise in blood pressurelManagement is CONTROVERSIAL.lSubarachnoid Hemorrhage:oral nimodipine(nimotop)60mg po q 4 hours to reverse vasospasm.lNicardipine:2mg IV boluses followed by an IV infusion of 4

14、 to 15 mg/hr is used by some to treat Subarachnoid Hemorrhage.Pathophysiology:Elevated Blood Pressure can be the cause of the central nervous system event,OR,it may be a normal physiologic response(Cushings Reflex)Ischemic CVA Management Favors lowering MAP(mean arterial pressure)by 20%.Recommends I

15、V Labetalol in small doses of 5mg increments IF Diastolic Blood Pressure is higher than 140 mmHg.(T.398)HPT RetinopathyAV crossing changesHPT retinopathyHPT retinopathyAorticDissectionCongestiveHeart FailureAcute MIPathophysiology:Increased Afterload with decreased Cardiac OutputCHF/Pulmonary EdemaS

16、ymptoms:Shortness of Breath,Cough,Chest Pain Lower Extremity SwellingSigns:Jugular Venous Distension,Rales,S3 Gallop Hepatomegaly,Pedal EdemaCHF/Pulmonary EdemaPathophysiology:-Increased afterload,cardiac workload,and myocardial oxygen demand-Decreased coronary artery blood flowAcute Coronary Syndro

17、me/Acute MISymptoms:Chest Pain,Nausea/Vomiting,Diaphoresis,Shortness of Breath Signs:Congestive Heart Failure Signs,S4 Gallop (due to decreased ventricular compliance)Few physical findings in many patients Clinical History is very ImportantAcute Coronary Syndrome/Acute MI-Immediate Blood Pressure re

18、duction is indicated to prevent Myocardial Damage-No specific Defined BP target Management:Nitroglycerin IV or Sublingual-Beta Blockers(Esmolol,Lopressor)-Nitroglycerin is Drug of ChoicePathophysiology:-Atherosclerotic Vascular Disease,Chronic Hypertension,increased shearing force on the thoracic ao

19、rta,leading to intimal tear.-50%begin in ascending aorta-30%at aortic arch-20%in descending aortaDissection of Thoracic Aorta Symptoms:-Chest pain radiating to the back(classic presentation)-Neurological Symptoms(carotid artery dissection)-Angina(coronary artery dissection)-Shortness of breath(aorti

20、c insufficiency,cardiac tamponade)Signs:-Differential Blood Pressure(in UE)-Bruit(interscapular)-Neurological Deficits-Acute Cardiac Tamponade(rare)Dissection of Thoracic AortaOptimal Blood Pressure in these patients is undefined and must be tailored for each patient,however,SBP of 120-130mmHg may b

21、e a intial starting point.(T.408)Acute Renal FailurePathophysiology:-Hypertensive Glomerulonephropathy,Acute Tubular Necrosis-Worsening renal function in the setting of severe hypertension with elevation of BUN/CR,proteinuria,or the presence of red cells and red cell casts in the urine.Acute Renal F

22、ailureSymptoms:-Many times there are few actual symptoms-Facial or Peripheral Edema due to fluid overload or proteinuria may be present,shortness of breathSigns:-Few findings unless edematous-Pulmonary EdemaAcute Renal FailureManagement:-Nitroprusside is agent of choice-Dialysis(as needed)-Lasix to

23、enhance Sodium excretion;Also recommends Nitroprusside or Nifedipine-Nitroglycerin is also a good agent in this setting since it is hepatically metabolized and gastrointestinally excreted.Pathophysiology:-Systemic arterial vasoconstriction(including placental,leading to decreased uterine blood flow)

24、.-Defined as SBP=140/90 mmHg or greater,OR a 20 mmHg rise in SBP or 10 mmHg rise in DBP from baseline and evidence of HELLP SyndromeSymptoms:lower extremity swelling,headache,confusion,seizures,comaSigns:edema,hyperreflexia,elevation of blood pressure related to baseline BP prior to pregnancy(elevat

25、ion may be mild 125/75)Management:IV Magnesium Sulfate,Hydralazine.-May also use nifedipine or labetalol Delivery of Fetus is definitive treatment of pre-eclampsia PheochromocytomaPathophysiology:-Alpha and Beta stimulation of the cardiovascular system due to adrenergic excess statesSymptoms:Episodi

26、c Headaches,flushing,tremor,diaphoresis,diarrhea,hyperactivity,and palpitationsSigns:Tachycardia,tachypnea,tremor,hyperdynamic state(high output CHF)PheochromocytomaManagement:-Alpha Blocker FIRST,followed by a Beta Blocker-Phentolamine(alpha)+Esmolol(beta)-Labetalol IV(combined alpha and beta block

27、ade)lRapid OnsetlRapid Maximal effectlRapid offsetlEase of TitrationParenteral Agents Oral Regimens for Treatment of Hypertensive Urgency in the ED -Clonidine:0.1 to 0.2mg PO,repeat 0.1mg q hour to desired BP reduction or max of 0.7mg.-Labetalol:200 to 400mg PO,repeat every 2 to 3 hours-Captopril:25

28、mg PO-Losartan:50mg PO lAcute End-organ damage determines hypertensive emergencylBe familiar with the agents of choice in specific emergencieslGoal for most is careful reduction of MAP by 20-25%over minutes to hoursDBP not less than 100 to 110Except:Pregnancy,Dissection,MI,lPatients without acute end-organ ischemia rarely require urgent intervention