1. Focus on
Hypertension

2. Hypertension: Definition
Persistent elevation of
 Systolic blood pressure ≥140 mm Hg
or
 Diastolic blood pressure ≥90 mm Hg
• Worldwide an estimated 1 billion people have
hypertension; about 1 in 3 Americans affected
• Direct relationship between hypertension and
cardiovascular disease (CVD)

3. Prehypertension: Definition
• Systolic blood pressure:
120–139 mm Hg
or
• Diastolic blood pressure:
80–89 mm Hg

4. Hypertension
• It is estimated that 1/3 of the general population in the US have
hypertension (Fields et al, 2004)
• Healthy People 2010: reduce the # of persons with HTN by
14%, increase the control of BP by 68%, increase the # of adults
taking action by weight loss, activity, low sodium diet by 98%
and increase the proportion of adults measuring their BP by
95%
• Risk of hypertension increases with age; if you don’t have it by
age 55 – 90% chance of getting it later in life
• CVD is #1 cause of death in women in US & other developed
areas of world; < 50% of women are aware of this fact See p.
762 for box at top of page with gender differences &
hypertension; Before age 55 hypertension more common in men
and they have MIs > 55 yrs, hypertension more common in
women and they have strokes

5. Factors Influencing
Blood Pressure (BP)
Systemic
Blood = Cardiac
x Vascular
Pressure Output
Resistance
Cardiac output is total blood flow through systemic or pulmonary
circulation per min. CO =stroke volume (amt pumped out of
L ventricle per beat [70 ml]) times the HR for 1 min.
SVR + force opposing movement of blood in vessels;
determined primarily by radius of small arteries & arterioles
Copyright © 2007, 2004, 2000, Mosby, Inc., an affiliate of Elsevier Inc. All Rights Reserved.

6. Factors Influencing BP
Cardiac
•Heart rate
•Inotropic state
•Neural (pons and medulla)
•Humoral (hormones)
Cardiac Output
Renal Fluid Volume Control
•Renin–angiotensin
•Aldosterone
•Atrial natriuretic factor
Copyright © 2007, 2004, 2000, Mosby, Inc., an affiliate of Elsevier Inc. All Rights Reserved.

7. Sympathetic Nervous System
• Baroreceptors
 Nerve cells in carotid artery & aortic arch
 Maintain BP during normal activities
 React to increases & decreases in BP
• BP – impulse to brain to inhibit SNS; HR
& force of ctrx; vasodilation of arterioles
• BP – activates SNS; vasoconstriction of
arterioles; HR & heart contractility

8. • Increased BP send inhibitory
impulse to sympathetic vasomotor
center in brainstem;
• In long-standing hypertension,
baroreceptors adjust to elevated BP
and reads it as normal; doesn’t make
adjustments; also becomes less
responsive in some older adults

9. Mechanism of Action of Aldosterone
Fig. 33-2
Increases CO by increasing blood volume
.

10. Blood Pressure Classification
Category SBP DBP
(mm Hg) (mm Hg)
Normal < 120 < 80
Prehypertension 120–139 80–89
Stage 1 hypertension 140–159 90–99
Stage 2 hypertension > 160 or > 100
Copyright © 2007, 2004, 2000, Mosby, Inc., an affiliate of Elsevier Inc. All Rights Reserved.

11. Etiology of Hypertension
• Primary (essential or idiopathic)
hypertension
 Elevated BP without an identified
cause
 90% to 95% of all cases

12. Etiology of Hypertension
• Primary (essential or idiopathic)
hypertension
 Contributing factors
• ↑ SNS activity
• ↑ Sodium retaining hormones and
vasoconstrictors
• Diabetes mellitus
• > Ideal body weight
• ↑ Sodium intake
• Excessive alcohol intake

13. Secondary Hypertension
 Elevated BP with a specific cause
• 5% to 10% of adult cases
 Contributing factors:
• Coarctation of aorta name given to a congenital condition whereby the aorta
narrows in the area where the ductus arteriosus (ligamentum arteriosum after regression) inserts.
• Renal disease
• Endocrine disorders
• Neurologic disorders
• Cirrhosis
• Sleep apnea
 If someone under 20 or over 50 suddenly develops
hypertension, esp. severe then suspect secondary cause

14. Risk Factors for - Primary Hypertension
• Age (>55)
• Alcohol
• Cigarette smoking
• Diabetes mellitus
• Elevated serum lipids
• Excess dietary sodium
• Gender
 SBP rises with age Alcohol – excessive use strongly correlated to
hypertension
 Smoking – increases risk for CV disease ; vasoconstriction
 Diabetes – along with hypertension greater risk for target organ disease and
usually more severe
 Hyperlipidemia elevated in people with hypertension; increases risk of
atherosclerosis
 Some pts Na sensitive Males have higher rates of hypertension <55 and
increased in women>55

15. Risk Factors for
Primary Hypertension
• Family history
• Obesity
• Ethnicity
• Sedentary lifestyle
• Stress

16. Pathophysiology of
Primary Hypertension
• Heredity
 In most cases, hypertension results from
the interaction of:
• Environmental factors
• Demographic factors
• Genetic factors

17. Primary Hypertension
• Water and sodium retention
 A high sodium intake may result in water
retention
 Some people are Na sensitive (about
20%) ; not everyone with high salt diet
develops hypertension

18. Pathophysiology of
Primary Hypertension
• Water and sodium retention
 Certain demographics are associated
with “salt sensitivity”
• Obesity
• Increasing age
• African American ethnicity
• People with diabetes, renal disease

19. Pathophysiology of
Primary Hypertension
• Stress and increased SNS activity
 Produces increased vasoconstriction
 ↑ HR
 ↑ Renin release
 Angiotensin II causes direct arteriolar
constriction, promotes vascular hypertrophy and
induces aldosterone secretion

20. Pathophysiology of
Primary Hypertension
• Insulin resistance & hyperinsulinemia
 High insulin concentration stimulates SNS
activity and impairs nitric oxide–mediated
vasodilation
 Not present in secondary hypertension and
don’t improve when hypertension is treated

21. Pathophysiology of
Primary Hypertension
• Altered renin–angiotensin mechanism
 High plasma renin activity
• Endothelial cell dysfunction
 Source of many vasoactive substances
 Role of endothelial cell dysfunction in cause and
treatment of hypertension is ongoing

22. • Renin is an enzyme released by the kidney to help control the body's
sodium-potassium balance, fluid volume, and blood pressure.
• Description
• When the kidneys release the enzyme renin in response to certain
conditions (high blood potassium, low blood sodium, decreased blood
volume), it is the first step in what is called the renin-angiotensin-
aldosterone cycle. This cycle includes the conversion of
angiotensinogen to angiotensin I, which in turn is converted to
angiotensin II, in the lung. Angiotensin II is a powerful blood vessel
constrictor, and its action stimulates the release of aldosterone from
an area of the adrenal glands called the adrenal cortex. Together,
angiotensin and aldosterone increase the blood volume, the blood
pressure, and the blood sodium to re-establish the body's sodium-
potassium and fluid volume balance. Primary aldosteronism, the
symptoms of which include hypertension and low blood potassium
(hypokalemia), is considered "low-renin aldosteronism."

23. Hypertension
Clinical Manifestations
• Referred to as the “silent killer”
• Frequently asymptomatic until target
organ disease occurs
 Or recognized on routine screening

24. Hypertension
Clinical Manifestations
• Sx often secondary to target organ
disease
• Can include:
 Fatigue, reduced activity tolerance
 Dizziness
 Palpitations, angina
 Dyspnea

25. Hypertension
Complications
• Target organ diseases occur most
frequently in:
 Heart
 Brain
 Peripheral vasculature
 Kidney
 Eyes

26. Hypertension
Complications
• Hypertensive
heart disease
 Coronary artery
disease
 Left ventricular
hypertrophy
 Heart failure
Increased systemic vascular resistance causes left ventricle to work to hard;
initially increases in size as compensatory mechanism; eventually becomes
too large and requires more oxygen and energy; can’t keep up with demand Fig. 33-3: Top, normal
and end up with heart failure heart; Bottom, left
ventricular hypertrophy

27. Hypertension-Complications
• Cerebrovascular disease
 Stroke
• Peripheral vascular disease
• Nephrosclerosis
• Retinal damage
• Atherosclerosis most common cause of cerebrovascular disease;
hypertension major risk factor for cerebral atherosclerosis and stroke
• Atherosclerosis in peripheral blood vessels too; can lead to PVD, aortic
aneurysm, aortic dissection
• Hypertension one of leading causes of end-stage renal disease, esp. in
African-Americans; some degree of renal dysfunction usual in person with
even mild BP elevations
• Retina is only place blood vessels can be directly visualized; if see damage
there then indicates damage in brain, heart, & kidney too; Can cause
blurring, retinal hemorrhage and blindness

28. Hypertension
Diagnostic Studies
• History and physical examination
• BP measurement in both arms
 Use arm with higher reading for subsequent
measurements
 BP highest in early morning, lowest at
night

29. Hypertension
Office BP Measurement
• Use auscultatory method with a properly calibrated
instrument
• Patient seated quietly for 5 min in a chair, feet on the floor,
and arm supported at heart level
• Appropriate-sized cuff is necessary to ensure accurate reading
• At least two measurements should be obtained
• Allow at least 1 minute between readings. If one arm higher
than other; take BP in higher arm for subsequent
measurements

30. Hypertension
Diagnostic Studies
• Urinalysis, creatinine clearance
• Serum electrolytes, glucose
• BUN and serum creatinine
• Serum lipid profile
• ECG
• Echocardiogram
• Know normal lab values! Use your lab book

31. Hypertension
Diagnostic Studies
• “White coat” phenomenon may precipitate the need
for ambulatory blood pressure monitoring (ABPM)
 Noninvasive, fully automated system that
measures BP at preset intervals over a 24-hour
period
 Also used when suspect drug resistance,
hypotensive symptoms with drug therapy,
episodic hypertension, or SNS dysfunction

32. Hypertension
Collaborative Care
• Overall goals
 Control blood pressure
 Reduce CVD risk factors
• Strategies for adherence to regimens
 Empathy increases patient trust, motivation,
adherence to therapy
 Consider patient’s cultural beliefs, individual
attitudes in formulating treatment goals

33. Benefits of Lowering BP
Average Percent Reduction
Stroke incidence 35%–40%
Myocardial infarction 20%–25%
Heart failure 50%

34. Collaborative Care
Lifestyle Modifications
• Wt. reduction
 10 kg (22 lb) loss; SBP by 5-20 mm Hg
• DASH eating plan (dietary approaches to stop
hypertension)
• Na reduction
 <2.4 g of sodium/day
• Moderate alcohol intake
 Men: 2 drinks/day or less
 Women: 1 drink/day or less

35. Collaborative Care
Lifestyle Modifications
• Physical activity:
 Regular physical (aerobic) activity,
 At least 30 min, most days of week
• Avoidance of tobacco products
• Stress management

36. Collaborative Care HTN
Drug Therapy
• Primary actions
 Reduce SVR
 Reduce volume of circulating blood
• Classifications
 Diuretics
 Adrenergic inhibitors
 Direct vasodilators
 Angiotensin inhibitors
 Calcium channel blockers
• Review pharmacology and know drug classes & how they
work to reduce BP; side effects
• See pps 773-776 in book for good overview!!!

37. Collaborative Care
Fig. 33-5

38. Treatment Algorithm
Fig. 33-4

39. Collaborative Care
Drug Therapy
• Patient teaching
 Identify, report, minimize side effects to
enhance compliance
• Orthostatic hypotension
• Sexual dysfunction
• Dry mouth
• Frequent urination

40. Collaborative Care
Nursing Management
Assessment
 Subjective data
• Past health history
• Medications
• Functional health patterns
 Objective data
• Target organ damage

41. Collaborative Care
Nursing Management
Nursing Diagnoses
• Ineffective health maintenance
• Anxiety
• Sexual dysfunction
• Ineffective therapeutic regimen management
• Disturbed body image
• Ineffective tissue perfusion

42. Collaborative Care
Nursing Management
Collaborative problems
• Potential complications:
• Adverse effects from antihypertensive
therapy
• Hypertensive crisis
• Stroke
• Myocardial infarction

43. Collaborative Care
Nursing Management
Planning
• Patient will:
 Achieve & maintain individually determined
goal BP
 Understand, accept, & implement therapeutic
plan
 Experience minimal/no unpleasant side effects
of therapy
 Be confident of ability to manage & cope with
condition

44. Collaborative Care
Nursing Management
Implementation
• Health Promotion
 Individual patient evaluation
 Blood pressure measurement
 Screening programs
 Cardiovascular risk factor modification

45. Collaborative Care
Nursing Management
Implementation
Ambulatory and Home Care
 Patient/family teaching:
• Nutritional therapy
• Drug therapy
• Physical activity
• Home monitoring of BP (if appropriate)
• Tobacco cessation (if applicable)

46. Collaborative Care
Nursing Management
Nursing Evaluation
• Patient will:
 Achieve & maintain goal BP as defined for the
individual
 Understand, accept, and implement the
therapeutic plan
 Experience minimal or no unpleasant side
effects of therapy

47. Hypertension in Older Persons
• Isolated systolic hypertension (ISH):
 Most common form of hypertension in people
> 50 years of age
• Lifetime risk of developing hypertension:
 About 90% for normotensive men and women over age 55
• Reasons for increased BP in elderly:
 Loss of elasticity
 Increased collagen and stiffness of myocardium
 Increased PVR
 Decreased adrenergic receptor sensitivity
 Blunting of baroreceptor reflexes
 Decreased renal function
 Decreased renin response to Na/H2O depletion
 May have altered drug absorption; delayed metabolism and excretion; be
careful when medicating

48. Hypertension in Older Persons
• More likely to have “white coat”
hypertension
• Often a wide gap between 1st Korotkoff
sound and subsequent beats called the
auscultatory gap
 Failure to inflate the cuff high enough
may result in seriously underestimating
the SBP

49. Hypertension in Older Persons
• Have varying degrees of impaired
baroreceptor reflex mechanisms
• Consequently, orthostatic hypotension
occurs often
 Especially in patients with ISH

50. Cultural and Ethnic Disparities
• In general, Trx similar for all
demographic & ethnic groups
• Prevalence & severity of HTN
increased in African Americans

51. Cultural and Ethnic Disparities*
• Mexican Americans less likely to receive
treatment than whites & African
Americans
• Mexican Americans & Native Americans
have lower rates of BP control than whites
and African Americans

52. Hypertensive Crisis
• Severe, abrupt increase in DBP
 Defined as >140 mm Hg
• Rate of increase in BP more important than absolute
value
• Often occurs in patients with Hx of HTN who failed to
comply with medications or who have been
undermedicated
• Monitor MAP mean arterial pressure: MAP = (SBP + 2DBP)
3

53. Hypertensive Crisis
Clinical Manifestations
• Hypertensive emergency = evidence
of acute target organ damage:
 Hypertensive encephalopathy, cerebral
hemorrhage
 Acute renal failure
 Myocardial infarction
 Heart failure with pulmonary edema

54. Hypertensive Crisis
Nursing & Collaborative Management
• Hospitalization
 IV drug therapy: Titrated to mean arterial pressure
 Monitor cardiac and renal function
 Neurologic checks
 Determine cause
 Education to avoid future crises
• Decrease BP by no more than 25% within 1st hr; then if
stable goal for BP is 190/100 over next 2-6 hrs
• Lowering BP too much or too quickly increases risk for
stroke, MI, renal failure due to decreased perfusion to these
vital organs

55. Hypertensive Emergency
• Develops over hours-days
• BP > 180/120 mm Hg
• Evidence of acute target organ damage, esp. to CNS
 Hypertensive encephalopathy
 Sx may be similar to stroke, but no focal or lateral signs
• Can see sudden rise in BP with HA, N&V, SZ, confusion,
stupor & coma; Increased ICP due to edema
• Common to have blurred vision and transient blindness
• Renal insufficiency to complete shutdown
• Rapid cardiac decompensation; MI, dyspnea

56. Hypertensive Urgency
• Develops over days to weeks
• BP severely elevated but no evidence of
target organ damage
 Usually treat with oral meds as outpatient

57. Supporting Materials
• Web site www.nhlbi.nih.gov
• For patients and the general public
 Facts about the DASH Eating Plan
 Your Guide to Lowering Blood Pressure
 My Blood Pressure Wallet Card
• For health professionals
 Reference Card