Transcript Hypertension

Hypertension
“the silent killer”
On completion of this chapter, the learner
will be able to:
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Define blood pressure and identify risk factors for
hypertension.
Explain the difference between normal blood pressure
and hypertension and discuss the significance of
hypertension.
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Describe the treatment approach for hypertension,
including lifestyle changes and medication therapy.
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Use the nursing process as a framework for care of the
patient with hypertension.
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Describe the necessity for immediate treatment of
hypertensive crisis.
Introduction:
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BP: The force of blood against the wall of the
arteries.
Blood pressure is the product of cardiac output
multiplied by peripheral resistance. Cardiac output is
the product of the heart rate multiplied by the stroke
volume. In normal circulation, pressure is exerted by
the flow of blood through the heart and blood
vessels. High blood pressure, known as hypertension,
can result from a change in cardiac output, a change
in peripheral resistance, or both.
Blood Pressure = Cardiac Output X
Resistance.
Peripheral Vascular
BP = CO X TPR
HR X SV
Definition of Hypertension:
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HT : is a systolic blood pressure
greater than 140 mmHg and a diastolic
pressure greater than 90 mm Hg.
Types of Hypertension:
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primary hypertension.
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Secondary hypertension.
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primary hypertension:
which refers to high blood pressure for which
no medical cause can be found. (About 90–
95%).
Secondary hypertension:
related to specific causes, such as narrowing
of the renal arteries, kidney abnormalities,
rare tumors, certain medications, pregnancy,
and stenosis of the aorta, (5–10%).
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High blood pressure can be viewed in three
ways: as a sign, a risk factor for
atherosclerotic cardiovascular disease, or a
disease.
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As a sign, nurses and other health care
professionals use blood pressure to monitor
a patient’s clinical status. Elevated pressure
may indicate an excessive dose of
vasoconstrictive medication or other
problems. As a risk factor, hypertension
contributes to the rate at which
atherosclerotic plaque accumulates within
arterial walls. As a disease, hypertension
is a major contributor to death from
cardiac, renal, and peripheral vascular
disease.
Pathophysiology :
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Several hypotheses about the pathophysiologic
bases of elevated blood pressure are associated
with the concept of hypertension as a
multifactorial condition. Given the overlap among
these hypotheses, it is likely that aspects of all of
them will eventually prove correct.
Hypertension may be caused by one or
more of the following:
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Increased sympathetic nervous system activity related
to dysfunction of the autonomic nervous system.
Increased renal reabsorption of sodium, chloride, and
water related to a genetic variation in the pathways
by which the kidneys handle sodium.
An overactive Renin-angiotensin system leads
to vasoconstriction and retention of sodium and
water. The increase in blood volume plus
vasoconstriction leads to hypertension.
Decreased vasodilation of the arterioles related to
dysfunction of the vascular endothelium.
Resistance to insulin action, which may be a common
factor linking hypertension, type 2 diabetes mellitus,
hypertriglyceridemia, obesity.
Risk Factors for HBP:
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Tobacco, alcohol, caffeine.
Obesity/Overweight.
Oral Contraceptives.
Stress.
Lack of exercise.
Poor Diet, Such as increased salt intake.
Aging- vessels lose elasticity (> 60 yrs age).
Heredity.
Race.
Clinical Manifestations :
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No symptoms - many people are unaware they have
hypertension until it is accidentally found at a doctor visit
or they develop complications of hypertension.
Non-specific symptoms - symptoms of hypertension may
be mild and vague:
Headache, Morning headache, Dizziness, Confusion,
Papilloedema, Fatigue, Shortness of breath, Convulsion
Changes in vision, Nausea, Vomiting, Anxiety, Increased
sweating, Nose bleeds, dizziness, weakness, hemiplegia.
Assessment and Diagnostic
Evaluation :
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Routine laboratory tests include urinalysis, blood
chemistry (ie, analysis of sodium, potassium, creatinine,
BUN, fasting glucose, and total and high-density lipoprotein
[HDL] cholesterol levels), and a 12-lead
electrocardiogram. Left ventricular hypertrophy can be
assessed by echocardiography.
CBC used to identify potential renal failure.
Chest x-ray, shows any enlargement of the heart
and pulmonary vein, presence of pulmonary
edema or pleural effusion
Management :
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Lifestyle Modifications for Hypertension
Prevention and Management.
PHARMACOLOGIC THERAPY.
1)- Lifestyle Modifications:
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Lose weight if overweight.
Limit alcohol intake .
Increase aerobic physical activity (30 to 45
minutes most days of the week).
Reduce sodium intake
Maintain adequate intake of dietary potassium
Maintain adequate intake of dietary calcium
and magnesium for general health.
Stop smoking and reduce intake of dietary
saturated fat and cholesterol for overall
cardiovascular health.
2)PHARMACOLOGIC THERAPY:
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Diuretics.
Calcium channel blocker.
Angiotensin converting enzyme inhibitirs
(ACE-I).
Vasodilators.
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Diuretics:
spironolactone (Aldactone).
Thiazide.
furosemide (Lasix).
to promote diuresis and block reabsorption
of sodium and water in the kidney.
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Calcium channel blocker(CCB):
Nifedipin
Amlodipine
Verapamil
to produce vasodilation on vascular
smooth muscle
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ACE – Inhibitors:
Enalapril
Captopril.
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Block the enzyme that converts angiotensin I
to angiotensin II ( a vasoconstrictor)
Promote vasodilatation
Lowers aldosterone secretion
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Vasodilators:
Hydralazine
Minoxidil
Sodium nitroprusside
to relax smooth muscle of arterioles
and reduce peripheral vascular
resistance and thus, blood pressure.
NURSING Diagnosis:
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Risk for decreased cardiac output.
Related to: vasoconstriction, increased
preload, increased afterload, ventricular
hypertrophy, ischemia
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Risk for altered tissue perfusion.
Related to: increased blood pressure,
decreased cardiac output.
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Anxiety.
Deficient knowledge.
Noncompliance with therapeutic.