Hypertension Definition the force exerted by the blood

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Hypertension Ø Definition: the force exerted by the blood against the walls of the

Hypertension Ø Definition: the force exerted by the blood against the walls of the bleed vessels ØAdequate to maintain tissue perfusion during activity and rest ØArterial blood pressure: primary function of cardiac output and systemic vascular resistance

Hypertension Arterial BP = Cardiac Output (CO) x Systemic vascular resistance (SVR) Cardiac Output

Hypertension Arterial BP = Cardiac Output (CO) x Systemic vascular resistance (SVR) Cardiac Output = stroke volume x beats per min Systemic vascular resistance = force opposing the movement of blood within the blood vessels What is the effect on BP if SVR increased

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System Ø Vascular Endothelium Ø Renal

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System Ø Vascular Endothelium Ø Renal System Ø Endocrine System

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS) – norepinephrine released from

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS) – norepinephrine released from sympathetic nerve endings - to receptors alpha 1, alpha 2, beta 1 & beta 2 ØReacts within seconds ØIncreases Heart Rate - chronotropic ØIncreased cardiac contractility - inotropic ØProduces widespread vasoconstriction in peripheral arterioles

Hypertension SNS Receptors Influencing B/P

Hypertension SNS Receptors Influencing B/P

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS)– ØSympathetic Vasomotor Center –

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS)– ØSympathetic Vasomotor Center – located in the medulla – interacts with many areas of the brain to maintain BP within normal range under various conditions ØExercise – changes to meet oxygen demand ØPostural Changes – peripheral vasoconstriction

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS) – ØBaroreceptors: specialized nerve

Hypertension Mechanisms that Regulate BP Ø Sympathetic Nervous System (SNS) – ØBaroreceptors: specialized nerve cells the carotid arteries and the aortic arch ØSensitive to BP changes: ØIncrease: Inhibits SNS – peripheral vessel dilation. Decreased heart rate, and decreased contractility of the heart + increased parasympathetic activity (vagus nerve) decreased heart rate ØDecrease: Activates SNS – peripheral vessel constriction, increased heart rate, and

Hypertension Mechanisms that Regulate BP Ø Vascular Endothelium ØSingle cell layer that lines the

Hypertension Mechanisms that Regulate BP Ø Vascular Endothelium ØSingle cell layer that lines the blood vessels ØProduce vasoactive substances: ØEDRF Endothelium-derive relaxing factor – Ø Helps maintain low arterial tone at rest Ø Inhibits growth of the smooth muscle layer Ø Inhibits platelet aggregation ØVasodilation – prostacyclin ØEndothelin (ET) potent vasoconstrictor Endothelial dysfunction may contribute to atherosclerosis & primary hypertension

Hypertension Mechanisms that Regulate BP Ø Renal System ØControl Na+ excretion & extracellular fluid

Hypertension Mechanisms that Regulate BP Ø Renal System ØControl Na+ excretion & extracellular fluid volume ØRenal - Renin-angiotensin-aldosterone ØRenin converts angiotensinogen to angiotensin I ØAngiotensin-converting enzyme (ACE) converts I into angiotsensin II ØImmediate: Vasoconstrictor – increased systemic vascular resistance ØProlonged: Stimulates the adrenal cortex to secret Aldosterone – Na+ and Water retention ØRenal Medulla - Prostaglandins - vasodilator

Hypertension Renin-Angiotensin

Hypertension Renin-Angiotensin

Hypertension Renin-Angiotensin System

Hypertension Renin-Angiotensin System

Hypertension Mechanisms that Regulate BP Ø Endocrine System ØStimulates the SNS with ØEpinephrine –

Hypertension Mechanisms that Regulate BP Ø Endocrine System ØStimulates the SNS with ØEpinephrine – increases HR and contractility ØActivates B 2 -adrenergic receptors in peripheral arterioles of skeletal muscle = vasodilation ØActivates A 1 -adrenergic receptors in peripheral arterioles of skin and kidneys = vasoconstiction ØAdrenal Cortex – Aldosterone – stimulates kidneys to retain Na+ ØIncreased Na+ stimulates posterior pituitary – ADH – reabsorbs ECF/water

Hypertension Aldosterone Mechanism • Increased Aldosterone = • Increases sodium reabsorption = • Increases

Hypertension Aldosterone Mechanism • Increased Aldosterone = • Increases sodium reabsorption = • Increases water reabsorption = • Increases blood volume = • Increases cardiac output

Hypertension Mechanisms that Regulate BP Ø Regulatory mechanisms in the health person function in

Hypertension Mechanisms that Regulate BP Ø Regulatory mechanisms in the health person function in response to the demands on the body Ø When Hypertension develops, one or more of these mechanisms are defective Ø Sympathetic Nervous System Ø Vascular Endothelium Ø Renal System Ø Endocrine System

Secondary Hypertension Pathophysiology Ø Specific cause of hypertension can be identified Ø 5+% of

Secondary Hypertension Pathophysiology Ø Specific cause of hypertension can be identified Ø 5+% of adult hypertension Ø Causes: Ø Coarctation or congenital narrowing of the aorta Ø Renal disease – renal artery disease / parenchymal Ø Endocrine disorders: Pheochromocytoma, Cushing Syndrome, Hyperaldosteronism Ø Neurology disorders – brain tumors / head injury Ø Sleep apnea Ø Medications – sympathetic stimulants

Hypertension Pathophysiology Ø Primary (Essential) Hypertension: ØElevated BP without an identified cause ØAccounts for

Hypertension Pathophysiology Ø Primary (Essential) Hypertension: ØElevated BP without an identified cause ØAccounts for 95% of all cases of hypertension ØCause – unknown ØContributing Factors: Increased SNS activity, overproduction of Na+ retaining hormones & vasoconstrictors, increased Na+ intake ØRisk Factors: Modifiable

Primary Hypertension Pathophysiology Ø Heredity – interaction of genetic, environmental, and demographic factors Ø

Primary Hypertension Pathophysiology Ø Heredity – interaction of genetic, environmental, and demographic factors Ø Water & Sodium Retention – 20% of pts with high Na+ diet develop HTN Ø Altered Renin-Angiotensin Mechanism – found in 20% of patients Ø Stress & Increased SNS Activity Ø Insulin Resistance & Hyperinsulinemia Ø Endothelial Cell Dysfunction

Hypertension Clinical Manifestation Dx is made after multiple readings over several weeks NIH/Joint Committee

Hypertension Clinical Manifestation Dx is made after multiple readings over several weeks NIH/Joint Committee Definition: Category Optimal Normal High Normal Systolic <110 <120 130 -139 and or Stage 1 Stage 2 Stage 3 140 -159 160 -179 =>180 or or or Diastolic < 80 <85 85 -89 90 -99 100 -109 => 110

Primary Hypertension Risk Factors Ø Age Ø Alcohol Ø Cigarette Smoking Ø Diabetes Mellitus

Primary Hypertension Risk Factors Ø Age Ø Alcohol Ø Cigarette Smoking Ø Diabetes Mellitus Ø Elevated serum lipids Ø Excess Na+ in diet Ø Gender Ø Family History Ø Obesity Ø Ethnicity Ø Sedentary Lifestyle Ø Socioeconomic Ø Stress

Primary Hypertension Clinical Manifestations Ø Target Organ Complications: Ø Myocardium – angina / left

Primary Hypertension Clinical Manifestations Ø Target Organ Complications: Ø Myocardium – angina / left ventricular hypertrophy Ø Brain – TIA / CVA Ø Peripheral vascular – Peripheral pulse change Ø Kidney – renal failure Creatinine / Proteinuria

Primary Hypertension Clinical Manifestations Ø “Silent Killer” – asymptomatic and insidious Ø Severe HTN

Primary Hypertension Clinical Manifestations Ø “Silent Killer” – asymptomatic and insidious Ø Severe HTN – fatigue, reduced activity tolerance, dyspnea, dizziness, palpitations, angina

Hypertension Medical Diagnosis Ø History and Physical Examination Ø Renal Function ØSerum Creatinine &

Hypertension Medical Diagnosis Ø History and Physical Examination Ø Renal Function ØSerum Creatinine & Urine Creatinine Clearance Ø Electrolytes – especially K+ Ø Blood Glucose Ø Serum Lipids/EKG Ø Ambulatory BP Monitoring

Primary Hypertension Medical Management Ø Risk Stratification ØLevel of BP ØPresence of Target Organ

Primary Hypertension Medical Management Ø Risk Stratification ØLevel of BP ØPresence of Target Organ Disease ØOther Risk Factors

Hypertension Medical Management Risk Stratification

Hypertension Medical Management Risk Stratification

Primary Hypertension Medical Management Ø Lifestyle modification Ø Nutritional therapy Ø Alcohol consumption Ø

Primary Hypertension Medical Management Ø Lifestyle modification Ø Nutritional therapy Ø Alcohol consumption Ø Physical activity Ø Tobacco avoidance Ø Stress management Ø Drug Therapy

Hypertension Nutrition

Hypertension Nutrition

Hypertension Risk Factor Modification

Hypertension Risk Factor Modification

Primary Hypertension Medical Management Stepped Approach Lifestyle modification Not at Goal BP Drug Therapy

Primary Hypertension Medical Management Stepped Approach Lifestyle modification Not at Goal BP Drug Therapy Not at Goal BP Substitute med / add a 2 nd med/ increase dose Not at Goal BP

Primary Hypertension Medical Management – Drug Therapy Ø Diuretics Ø Thiazide Ø Loop Ø

Primary Hypertension Medical Management – Drug Therapy Ø Diuretics Ø Thiazide Ø Loop Ø K+ Sparing Ø Adrenergic Blockers/ Inhibitors Ø B-Adrenergic Blockers Ø Central Acting Adrenergic Antagonists Ø Peripheral Acting Adrenergic Antagonists Ø A-Adrenergic Blockers Ø Vasodilators Ø Angiotensin Inhibitors Ø Calcium Channel Blockers

Hypertension Medication - Diuretics

Hypertension Medication - Diuretics

Hypertension Medication – Beta-blocking Agents

Hypertension Medication – Beta-blocking Agents

Hypertension Medication Calcium Channel Blockers

Hypertension Medication Calcium Channel Blockers

Hypertension Medication Alpha Agonists & Vasodilators

Hypertension Medication Alpha Agonists & Vasodilators

Hypertension Antihypertensive Drug Therapy

Hypertension Antihypertensive Drug Therapy

Primary Hypertension Lack of Responsiveness to Therapy Ø Nonadherence to Therapy Ø Drug-Related Causes

Primary Hypertension Lack of Responsiveness to Therapy Ø Nonadherence to Therapy Ø Drug-Related Causes Ø Associated conditions Ø Secondary Hypertension Ø Volume overload

Primary Hypertension Hypertensive Crisis Ø Definition: Severe & abrupt elevation of BP with diastolic

Primary Hypertension Hypertensive Crisis Ø Definition: Severe & abrupt elevation of BP with diastolic > 120 -130 mm Hg. Ø Causes: ØNonadherence, renovascular changes, preeclampsia, Pheochromocytoma, Rebound from abruptly stopping beta blockers, head injury, necrotizing vasculitis, acute aortic dissection Ø Hypertensive Encephalopathy: Øheadache, N/V, confusion, obtunded, stuporous, seizures, blurred vision, transient blindness

Primary Hypertension Nursing Diagnoses Assess: Cardiovascular status; adherence to therapy; family interaction; risk factor

Primary Hypertension Nursing Diagnoses Assess: Cardiovascular status; adherence to therapy; family interaction; risk factor modification? Nsg Action: Supportive & reality-based; Administer meds; referrals; diagnostic preps; ask questions; supportive care during hospitalization for acute crisis Pt/Family Education: Medications; risk factor modification; Community support

Hypertension Dynamics of Treatment

Hypertension Dynamics of Treatment

Primary Hypertension Case Study

Primary Hypertension Case Study