final bnpcw hypertension

8/14/2019 Final Bnpcw Hypertension

http://slidepdf.com/reader/full/final-bnpcw-hypertension 1/28

AntihypertenAntihyperten

sivesive drugsdrugs



Blood PressureBlood Pressure



Normal Regulation Of BloodNormal Regulation Of Blood

PressurePressure



Contd.,Contd.,



Contd.,Contd.,

Any condition that affectsAny condition that affects heart rateheart rate,, stroke volumestroke volume or or

peripheral vascular resistance peripheral vascular resistance affectsaffects arterial blood pressurearterial blood pressure

Compensatory mechanisms to maintain balance betweenCompensatory mechanisms to maintain balance betweenhypotension and hypertensionhypotension and hypertension

Vascular endothelium produces vasodilating substances

(nitric oxide, prostacyclin) which reduce blood pressure



Contd.,Contd.,

BP regulation operates in aBP regulation operates in a negative feedback systemnegative feedback system

BaroreceptorsBaroreceptors andand chemoreceptorschemoreceptors in thein the carotid arteriescarotid arteries andand aorticaorticarcharch detect changes in arterial blood pressure and indetect changes in arterial blood pressure and in pO2, pCO2 pO2, pCO2 andand H+H+..

Increased BP results inIncreased BP results in increased stretchincreased stretch of vessels; activation of of vessels; activation of vagus and stimulation of medulla via sympathetic or vagus and stimulation of medulla via sympathetic or parasympathetic pathways. parasympathetic pathways.



Contd.,Contd.,

Normally, when the arterial blood pressure is elevated Normally, when the arterial blood pressure is elevatedKidneysKidneys will excrete more fluidwill excrete more fluid

Fluid lossFluid loss will result inwill result in decreased ECF volumedecreased ECF volume andand blood blood

volumevolume

Decreased blood flowDecreased blood flow to the heart willto the heart will reduce cardiac outputreduce cardiac output

Decreased CODecreased CO reduces arterial blood pressurereduces arterial blood pressure



Compensatory mechanismsCompensatory mechanisms

Baroreceptor reflexBaroreceptor reflex ↑BPBP → ↑baroreceptor stretchbaroreceptor stretch → ↑afferent nerve trafficafferent nerve traffic

activity inhibitsactivity inhibits vasomotor centrevasomotor centre

↓Sympathetic toneSympathetic tone

↓HR,HR, ↓

LV contractility (LV contractility (↓

SV) andSV) and

arteriolar vasodilatationarteriolar vasodilatation → ↓BPBP



Baroreceptor reflexBaroreceptor reflex



DefinitionDefinition

Elevation of Elevation of arterial blood pressure abovearterial blood pressure above140/90 mm Hg140/90 mm Hg. Can be caused by:. Can be caused by: an underlying disease processan underlying disease process

((secondary hypertensionsecondary hypertension))• Renal artery stenosisRenal artery stenosis

• HyperaldosteronismHyperaldosteronism

• pheochromocytomapheochromocytoma

• Cushing’syndromeCushing’syndrome idiopathic process (idiopathic process (primaryprimary or or essentialessential

hypertensionhypertension))



Types of HypertensionTypes of Hypertension

Essential or primaryEssential or primary —etiology ?. Contributors include: salt —etiology ?. Contributors include: salt

sensitivity, insulin resistance, genetics, sleep apnea, environmentalsensitivity, insulin resistance, genetics, sleep apnea, environmental

factors,othersfactors,others

SecondarySecondary —renal, adrenal, coarctation of aorta,steroids, pregnancy, —renal, adrenal, coarctation of aorta,steroids, pregnancy,

pheochromocytoma, primary aldosteronism, cushing’s syndrome pheochromocytoma, primary aldosteronism, cushing’s syndrome



JNC VII Causes of Secondary HypertensionJNC VII Causes of Secondary Hypertension

Medical Conditions

Chronic kidney disease

Primary hyperaldosteronism

Renovascular disease

Chronic steroid therapy

Cushing’s syndrome

Pheochromocytoma

Aortic coarctation

Thyroid or parathyroid disease

Sleep apnea

Drugs

NSAIDS

Oral contraceptives

Adrenal steroids

Sympathomimetics

Cyclosporine or tacrolimus

Erythropoietin

Ephedra, mu huang, bitter orange

Cocaine or amphetamines

Alcohol



Essential HypertensionEssential Hypertension

Activation of Activation of sympathetic nervous systemsympathetic nervous system

causing prolongedcausing prolonged vasoconstrictionvasoconstriction

Activation of Activation of RAASRAAS plays integral part as wellplays integral part as well

In combination, mechanisms cause prolongedIn combination, mechanisms cause prolongedincreased vascular resistance; this in turn resultsincreased vascular resistance; this in turn results

in a thickening of vessel walls,in a thickening of vessel walls, LessLess productionproduction

of of nitric oxide (vasodilator)nitric oxide (vasodilator) andand IncreasedIncreased

endothelin 1 (increased vascular tone)endothelin 1 (increased vascular tone)



Essential HypertensionEssential Hypertension Contd..Contd..

Also felt thatAlso felt that hyperinsulinemiahyperinsulinemiaandand insulin resistanceinsulin resistance causecause

endothelial dysfunction byendothelial dysfunction by

enhanced oxygen free radicalenhanced oxygen free radical

mediated damage andmediated damage and

decreaseddecreased ↓↓nitric oxidenitric oxide

bioavailabilitybioavailability. Also is an. Also is an

increased sympatheticincreased sympatheticresponse ;results in increasedresponse ;results in increased

vascular tone andvascular tone and constrictionconstriction



Normal Normal

(SBP)(SBP) <120<120 / (DBP)/ (DBP) <80<80 mmHgmmHg

PrehypertensionPrehypertension

SBPSBP 120-139120-139 / DBP/ DBP 80-8980-89 mmHgmmHg

Stage 1 HypertensionStage 1 Hypertension

SBPSBP 140-159140-159 / DBP/ DBP 90-9990-99 mmHgmmHg

Stage 2 HypertensionStage 2 Hypertension

SBPSBP >> 160160 / DBP/ DBP >> 100100 mmHgmmHg

Blood Pressure ClassificationBlood Pressure Classification

according to the JNC 7according to the JNC 7



Major Risk Factors That IncreaseMajor Risk Factors That Increase

Mortality in HypertensionMortality in Hypertension

SmokingSmoking

DyslipidemiasDyslipidemias

Diabetes MellitusDiabetes Mellitus

Age >60Age >60

Gender: men, postmenopausal womenGender: men, postmenopausal women Family historyFamily history



NonpharmacologicNonpharmacologic

Management of HypertensionManagement of Hypertension

Weight reductionWeight reduction

ExerciseExercise Salt restriction in dietSalt restriction in diet

Stress reductionStress reduction

DASH eating planDASH eating plan Moderation in alcohol intakeModeration in alcohol intake



Antihypertensive DrugsAntihypertensive Drugs

Classes:Classes: Angiotensin converting enzyme inhibitors (ACEI)Angiotensin converting enzyme inhibitors (ACEI) Angiotensin II Receptor BlockersAngiotensin II Receptor Blockers AntiadrenergicsAntiadrenergics Calcium channel blockersCalcium channel blockers DiureticsDiuretics

Direct vasodilatorsDirect vasodilators Renin inhibitorsRenin inhibitors



ACE Inhibitor: Mechanism of ActionACE Inhibitor: Mechanism of Action

Angiotensin II

Kininase II

Angiotensin I

Angiotensinogen

Inhibitor ACE

ReninBradykinin

Inactive Fragments

Sympathetic

Vasopressin

Aldosterone

Vasoconstriction

ACE=Angiotensin converting enzyme

Kininogen

Kallikrein

Vasodilation

Prostaglandins

tPA



ACE IACE I

final bnpcw hypertension

Documents