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Chapter 37
Hypertension
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Learning Objectives
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Define hypertension.
Explain the physiology of blood pressure regulation.
Discuss the risk factors, signs and symptoms, diagnosis,
treatment, and complications of hypertension.
Identify the nursing considerations when administering
selected antihypertensive drugs.
List the data to be collected for the nursing assessment
of a person with known or suspected hypertension.
Identify the nursing diagnoses, goals, and outcome criteria
for the patient with hypertension.
Describe the nursing interventions for the patient with
hypertension.
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Definitions
• The Seventh Report of the Joint National
Committee on Prevention, Detection,
Evaluation, and Treatment of High Blood
Pressure
• Normal blood pressure
• Systolic: <120 mm Hg; diastolic <80 mm Hg
• Prehypertension
• Systolic pressures between 120 and 139; diastolic
pressures between 80 and 89
• Stage 1 and stage 2 hypertension
• See Table 37-1
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Types of Hypertension
• Primary hypertension
• 90% to 95% of all cases of hypertension
• Its cause is unknown
• Secondary hypertension
• Caused by underlying factors, such as kidney
disease, certain arterial conditions, some drugs, and
occasionally pregnancy
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Anatomy and Physiology of
Blood Pressure Regulation
• Cardiac output
• The volume of blood pumped by the heart in a
specific period (usually 1 minute)
• Determined by strength, rate, and rhythm of the
contraction of the left ventricle and the blood volume
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Anatomy and Physiology of
Blood Pressure Regulation
• Peripheral vascular resistance
• Force in the blood vessels that left ventricle must
overcome to eject blood from the heart
• Resistance to blood flow determined by diameter of
the blood vessels and blood viscosity (thickness)
• Increased peripheral vascular resistance: the most
prominent characteristic of hypertension
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Anatomy and Physiology of
Blood Pressure Regulation
• Diameter of blood vessels regulated by the
vasomotor center
• Sympathetic nervous system tracts from the
medulla extend down the spinal cord to the
thoracic and abdominal regions
• Stimulation of sympathetic nervous system
causes release of the hormones
norepinephrine and epinephrine
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Anatomy and Physiology of
Blood Pressure Regulation
• Norepinephrine and epinephrine
(catecholamines) are vasoconstrictors: cause
blood vessels to constrict, making diameter
smaller
• By constricting blood vessels, norepinephrine
increases peripheral vascular resistance and
raises blood pressure
• Epinephrine constricts blood vessels and
increases the force of cardiac contraction,
causing blood pressure to rise
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Anatomy and Physiology of
Blood Pressure Regulation
• Vasoconstriction decreases blood flow to the
kidneys, which then release renin
• Renin leads to the formation of angiotensin,
another potent vasoconstrictor
• Angiotensin stimulates the adrenal cortex to
secrete aldosterone, a hormone that promotes
sodium and water retention
• This results in an increased blood volume
• Vasoconstriction, cardiac stimulation, and
retention of fluid all contribute to hypertension
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Figure 37-1
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Age-Related Changes
Affecting Blood Pressure
• Atherosclerotic changes reduce the elasticity of
the arteries, causing decrease in cardiac
output and increase in peripheral vascular
resistance
• Pulse pressure (the difference between the
systolic and diastolic pressures) widens in
response to a decreased ability of the aorta to
distend
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Primary (Essential) Hypertension
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Risk Factors
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Dyslipidemia
Atherosclerosis
Diabetes mellitus
Tobacco use
Age >55 years for men or age >65 years for
women
• Family history
• Father or brother with heart disease before age 55;
mother or sister with heart disease before age 65
• Sedentary lifestyle
• Obesity
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Signs and Symptoms
• Occipital headaches that are more severe on
arising
• Lightheadedness
• Epistaxis
• If hypertension has damaged blood vessels in
the heart, kidneys, eyes, or brain, patient may
have symptoms of impaired function of those
organs
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Figure 37-2
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Complications
• Heart
• Coronary artery disease develops in patients with
hypertension two to three times more frequently
than in people with normal blood pressures
• Kidneys
• Narrowing of the renal arteries may decrease renal
function and lead to chronic renal failure
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Complications
• Brain
• Prolonged hypertension constricts and damages
cerebral arteries, putting patient at risk for transient
ischemic attacks and cerebrovascular accidents
• Eyes
• Damage to eyes may include narrowing of the
retinal arterioles, retinal hemorrhages, and
papilledema; may lead to blindness
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Diagnostic Tests and Procedures
• Confirmed by repeated findings of average
pressures equal to or greater than 140/90
• Ambulatory blood pressure monitors
• Physician collects data about patient’s lifestyle,
other cardiovascular risk factors, and other
medical diagnoses
• Electrocardiogram
• Blood studies include glucose, hematocrit,
potassium, calcium, creatinine, and a lipid
profile
• Chest radiograph
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Medical Treatment
• Lifestyle modifications
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Weight reduction
Smoking cessation
Sodium and alcohol restriction
Exercise
Relaxation techniques
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Medical Treatment
• Pharmacologic therapy
• Specific antihypertensive drugs
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Diuretics
Beta-adrenergic receptor blockers
Calcium antagonists
Angiotensin-converting enzyme (ACE) inhibitors (or ACEIs)
Angiotensin II receptor antagonists (ARBs)
Central adrenergic blockers
Alpha-adrenergic receptor blockers
Direct vasodilators
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Figure 37-3
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Medical Treatment
• Pharmacologic therapy
• Nursing implications
• Administering the drugs to inpatients
• Monitoring for therapeutic and adverse effects
• Teaching patients about their drugs
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Secondary Hypertension
• Has a specific known cause and is less
common than primary hypertension
• Causes
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Renal disease
Excess secretion of adrenal hormones
Narrowing of the aorta
Increased intracranial pressure
Some drugs such as vasoconstrictors
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Nursing Care of the
Patient with Hypertension
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Assessment
• Periodic blood pressure checks detect new or
unknown hypertensive people; provide data to
evaluate effect of therapy in hypertensive
people
• Complete history and physical examination by
the registered nurse
• The LVN may be involved in initial blood
pressure screenings and monitoring, and
provides important data to evaluate treatment
effectiveness
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Health History
• Explore past medical for hypertension or renal,
cardiac, or endocrine disorders
• Date and readings of the last blood pressure
measurement
• Ask about pregnancy and about hormone
replacement therapy
• Current medications, including over-thecounter drugs
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Health History
• Family health history: hypertension, myocardial
infarction, or cerebrovascular accidents
• Body systems for signs and symptoms,
particularly headaches, epistaxis, dizziness,
visual disturbances, dyspnea, angina, nocturia
• Data about the patient’s usual functioning may
detect some risk factors for hypertension
• Occupation, exercise and activity, sleep and rest,
nutrition, interpersonal relationships, and stressors
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Physical Examination
• General appearance; note obvious distress
• Measure height and weight and vital signs
• Patient should be seated in a chair with feet on
the floor and arm resting at the level of the
heart
• The proper cuff size is essential
• Multiple readings should be taken
• Blood pressure assessed in both arms in the
supine, sitting, and standing positions
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Interventions: Ineffective Therapeutic
Regimen Management
• Diet therapy goals
• Maintain ideal body weight; prevent fluid retention
• Exercise
• Walking is highly recommended: increases
cardiovascular functioning, burns calories, relieves
stress, and promotes a sense of well-being
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Interventions: Ineffective Therapeutic
Regimen Management
• Stress management
• Help patients identify stressors in their lives and
explore ways to reduce them
• Drug therapy
• Review the name, dosage, purpose, and side
effects of any prescribed medications
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Interventions
• Risk for Injury
• Orthostatic hypotension
• Sudden drop in systolic blood pressure, usually 20 mm Hg,
when going from lying or sitting to a standing position
• Monitor for lightheadedness, dizziness, syncope
• Sedation
• Advise if drowsiness is likely so activities requiring
alertness can be avoided during times of peak drug effect
• Taking medications at bedtime to promote sleep
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Interventions
• Ineffective Coping
• If depression a side effect of an antihypertensive,
consult physician to substitute another drug
• Sexual Dysfunction
• Decreased libido, inability to achieve an erection, or
delayed ejaculation
• Advise physician so an alternative medication or
other intervention can be considered
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Older Patients
• Response to drug therapy more difficult to
predict; side effects are more common
• Orthostatic hypotension and sedation problematic
for the older person, who is prone to fall and suffer
serious injuries
• Depression also must be taken very seriously
because it lowers motivation, impairs quality of life,
and can lead to suicide
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Hypertensive Emergencies
• A life-threatening medical emergency
• Severe headache, blurred vision, nausea,
restlessness, and confusion
• Elevated diastolic blood pressure (130 mm Hg
or more); the heart and respiratory rates are
increased
• May result from having stopped taking
antihypertensive drugs
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Hypertensive Emergencies
• Causes: malignant hypertension, hypertensive
encephalopathy, eclampsia,
pheochromocytoma (adrenal tumor),
cerebrovascular accident
• Without treatment, the patient in hypertensive
crisis may incur cardiac and renal damage
• Death may ensue as a result of a
cerebrovascular accident, renal failure, or
cardiac failure
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Medical Diagnosis
• Assessment in the ED reveals elevated blood
pressure, pulse, and respiratory rate
• Retinal hemorrhage or papilledema, or both,
observed in fundus (back, interior portion) of
eye
• Physician may order blood drawn for arterial
blood gases, CBC, electrolytes, blood urea
nitrogen, creatinine, and cardiac enzymes
• Chest radiograph may be requested
• Direct blood pressure monitoring through an
arterial catheter preferred
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Medical Treatment
• The goal of drug therapy is to rapidly reduce
the pressure to a non–life-threatening level and
then to bring it slowly within normal range
• Diuretics and potent vasodilators
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Fenoldopam
Nitroglycerin
Diazoxide
Hydralazine
Phentolamine
Labetalol
Nitroprusside
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Medical Treatment
• An intravenous line is usually established
because many drugs are given by that route
• Oral options for the management of
hypertensive crisis include captopril, clonidine,
and nifedipine
• See Box 37-3, p. 728
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Nursing Care of the
Patient in Hypertensive Crisis
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Assessment
• Frequently check blood pressure, pulse,
respiration, and level of consciousness
• Some drugs are given in intravenous fluids,
requiring continuous monitoring and
adjustment
• Careful record of fluid intake and output
• Nausea and vomiting may indicate an
impending seizure or coma
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Interventions
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Administer prescribed drugs
Vital signs before and after each dose
Monitor cardiac and renal function
Start and maintain intravenous therapy
Administer oxygen as ordered
Comfort the patient
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Interventions
• Take appropriate safety measures if the patient
shows signs of seizure activity or a decreasing
level of consciousness
• Once patient’s condition improves, it is
important to explain how to manage
hypertension and prevent future crises
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