Download Drug Therapy for Hypertension

Chapter 22:
Drugs Used to Treat
Hypertension
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Lesson 22.1:
Hypertension, Lifestyle Modification, Options for
Treatment, and Nursing Care
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Objectives
1. Differentiate between primary and secondary hypertension.
2. Summarize nursing assessments and interventions used for
the treatment of hypertension.
3. Identify recommended lifestyle modifications for a
diagnosis of hypertension.
4. Identify initial options and progression of medicines
used to treat hypertension.
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Hypertension
pg335
 Characterized by an elevation of systolic blood pressure (sbp),
diastolic blood pressure (dbp), or both
 Primary hypertension: 90% of cases, unknown cause
 Secondary hypertension: occurs after another disorder
 Normal BP: less than 120 sbp, less than 80 dbp
 Prehypertension: 120 to 139 sbp, or 80 to 89 dbp
 Stage I: 140 to 159 sbp or 90 to 99 dbp
 Stage 2: greater than or equal to160 sbp or greater than or equal
to 100 dbp
• National High Blood Pressure Committee encourages practitioners to use
systolic pressure as the determinant for diagnosis.
• Treatment is important because control of hypertension reduces the
frequency of cardiovascular disease.
• More than 50 million people in the United States are affected.
Audience Response Question 1
 Which range of systolic blood pressure is classified as
prehypertension?
a)
b)
c)
d)
110 to 119
120 to 139
130 to 149
140 to 159
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Answer: b
Rationale: The category of prehypertension
(systolic 120 to 139, diastolic 80 to 89) was added
to the classification system in the JNC 7 report in
2003 because of the very high likelihood of
people with a blood pressure in this range of
having a heart attack, heart failure, stroke,
and/or kidney disease. People within this range
are in need of increased education and lifestyle
modification to gain control of their blood
pressure to prevent cardiovascular disease.
Audience Response Question 2
 Which ethnic group tends to have the highest incidence of
hypertension?
a)
b)
c)
d)
Caucasian
Asian
African American
Hispanic
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Answer: c
Rationale: In every age group, the
incidence of hypertension is
higher for African Americans
than whites of both genders. In
every cultural group, there is an
increased incidence of
hypertension when coupled with
obesity, elevated blood lipids, and
inactivity.
pg342
Nursing Assessments for Patients with
Hypertension
 Blood pressure sitting for 5 minutes quietly; no recent





caffeine products. Use appropriately sized cuff
Family history and risk factors present
Laboratory data for lipids, triglycerides, cholesterol, renal
function studies
BMI
Peripheral pulses
Patient education focuses on lifestyle modifications
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg336
Major Risk Factors of Hypertension
 Smoking
 Obesity
 Physical inactivity
 Dyslipidemia
 Diabetes mellitus
Increased circulation of cholesterol
causes plaque formation within blood
vessel walls, resulting in a narrowed
lumen, which increases vascular
resistance.
 Microalbuminuria or estimated glomerular filtration rate
(GRF) less than 60 mL/min
 Age (older than 55 for men, older than 65 for women)
 Family history of premature cardiovascular disease
 Race: African American
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Consequences of Hypertension
 Target organ damage
 Heart
 Brain
 Kidneys
 Blood vessels
 Eyes
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Options and Progression of Treatment
for Hypertension
 Long-term success depends on patients understanding the
characteristics and diseases that contribute to the issue
 Demographic characteristics—age, gender, race
 Coexisting diseases and risk factors—migraine headaches,
dysrhythmias, angina, diabetes mellitus, previous therapy used,
concurrent therapy, cost of treatment
The nurse must be willing to explore with the patient all
aspects of therapy and the need for continual control of
hypertension while avoiding potential adverse effects.
pg338
Management of Hypertension
 Lifestyle modifications are initial therapy
 If no significant effect, drug therapy is introduced
 Start with diuretics for stage 1 hypertension
 Add beta blockers, ACE inhibitors, calcium channel blockers,
and angiotensin receptor blockers as tolerated
 Start with two-drug combination for stage 2 hypertension
• Goal of blood pressure less than 140/90 mm Hg, or less than 130/80 mm
Hg for patients with diabetes or chronic kidney disease.
• Additional drugs are added until target blood pressure is achieved.
pg344
Medication Regimen Patient Education
 Drowsiness may occur within first 2 weeks
 Orthostatic hypotension precautions
 Leg exercises prevent blood pooling in legs
 Take blood pressure and record readings as prescribed
 Report lack of response to medication prescribed
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Audience Response Question 3
 A patient is diagnosed with hypertension. What is the initial
recommendation for this patient likely to be?
a)
b)
c)
d)
Beta-adrenergic blocking agent
Diuretic
Angiotensin-converting enzyme (ACE) inhibitor
Diet and exercise
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Answer: d
Rationale: Education should
begin first to attempt to reduce
modifiable risk factors. The
patient should be reevaluated in
about 2 months to see if blood
pressure has been lowered. If it
has not, drug therapy may be
necessary.
Patient Education and Health
Promotion
 Lifestyle modifications
 Smoking cessation
 Weight reduction
 DASH diet
 Physical activity
 Restriction in alcohol intake
 Stress reduction
 Regular sleep pattern of at least 7 hours each night
 Sodium control
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Fostering Health Maintenance
 Discuss how medication will benefit the patient
 Lifestyle changes are equally important to drug therapy
 Patient motivation improves when the patient has a positive
experience with health care provider
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Drug Therapy for Hypertension
Objective
5. Identify and summarize the action of
five drug classes used to treat
hypertension.
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Drug Classes Used for Hypertension
Management
 Diuretics; beta-adrenergic blocking agents
 ACE inhibitors; angiotensin II receptor blockers (ARBs)
 Direct renin inhibitors; aldosterone receptor antagonist
 Calcium channel blockers; alpha-1 adrenergic blocking
agents
 Central-acting alpha-2 agonists; peripheral-acting adrenergic
antagonists; direct vasodilators
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg344
Drug Class: Diuretics
 Actions
 Cause volume depletion, sodium excretion, vasodilation of
peripheral arterioles
 Uses
 Most commonly prescribed antihypertensives
 In combination with other antihypertensive agents
 Discussed further in Chapter 29
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg345
Drug Class: Beta-Adrenergic Blocking
Agents
 Actions
 Inhibit cardiac response to sympathetic nerve stimulation
 Inhibit renin release from kidneys
 Uses
 Initial therapy for stage 1 and 2 hypertension
 Common adverse effects
 Bradycardia, peripheral vasoconstriction (purple, mottled skin);
heart failure; bronchospasm, wheezing; masks hypoglycemia in
diabetic patients
• Not effective for African
Americans.
• Sudden discontinuation of therapy
results in exacerbation of anginal
symptoms.
Beta-Adrenergic Blocking Agents
(cont.)
 Hold medication if systolic BP is less than 100 mm Hg or if
heart rate is less than 60 bpm; contact prescriber
 Sudden discontinuation of therapy has resulted in worsening
angina, MI; medication should be gradually reduced over 1-2
weeks
 NSAIDs may inhibit effectiveness
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg345
Audience Response Question 4
 A patient has been taking a beta blocker for several months to
control hypertension and has no medications left. She calls the
clinic on Friday to request a refill, but the health care provider
has left the clinic for the weekend. The nurse should:
a) ask the patient to call back early Monday morning.
b) tell the patient to try to have a stress-free weekend.
c) tell the patient to avoid salt over the weekend.
d) contact the on-call provider for a refill approval.
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Answer: d
Rationale: Abrupt withdrawal of
a beta blocker can possibly result
in an MI. The nurse should
contact the provider for a refill
approval.
Drug
Class:
ACE
Inhibitors
 Actions
 Inhibit angiotensin I converting enzyme (ACE), disrupting the
conversion of angiotensin I to angiotensin II; reduce blood pressure;
preserve cardiac output; and increase renal blood flow
 Uses
 Single therapy for stage 1 or 2 hypertension
 Not as effective in African Americans unless combined with diuretic
 Common adverse effects
 Nausea, fatigue, headache, diarrhea; orthostatic hypotension, about
one-third of patients get a cough
• Understanding the renin-angiotensin-aldosterone system
(RAAS) is critical to understanding the actions of most
antihypertensives. Hold medication/contact prescriber if
.
systolic BP < 100 mm Hg.
ACE Inhibitors (cont.)
 Serious adverse effects
 Angioedema (swelling of the face, eyes, lips, and tongue;
difficulty breathing)
 Initial doses may cause hypotension with dizziness, tachycardia,
and fainting (more likely with older adults)
 Neutropenia
 Hyperkalemia
 Nephrotoxicity
 May cause fetal harm
 May increase blood levels of digoxin and lithium
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Audience Response Question 5
 Up to one-third of patients who take ACE inhibitors for
hypertension report which symptom after beginning therapy?
a)
b)
c)
d)
Chronic cough
Renal failure
Decreased white blood cells
Swelling of the face and lips
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Answer: a
Rationale: Many patients taking ACE inhibitors
may develop a chronic, dry, nonproductive,
persistent cough thought to be due to an
accumulation of bradykinin. It may appear from
1 week to 6 months after initiation of ACE
inhibitor therapy. Women appear to be more
susceptible than men. It may be severe enough
that the patient must stop the drug and replace
it with an angiotensin II receptor blocker
(ARB). The cough resolves within 1 to 30 days
after discontinuation of ACE inhibitor therapy.
pg349
Drug Class: ARBs
 Actions
 Bind to angiotensin II receptor sites and block the
vasoconstrictor from binding to receptor sites in target organs
 Uses
 Alone or in combination with other antihypertensives to reduce
blood pressure
 African Americans may not respond well to therapy with an
ARB only
 Common adverse effects
 Dyspepsia, cramps, diarrhea; headache; orthostatic hypotension
Copyright © 2017 Elsevier Inc. All Rights Reserved.
ARBs (cont.)
 Serious adverse effects
 Hyperkalemia, more common in patients with renal
impairment or DM
 Monitor potassium levels
 Discourage potassium or dietary supplements
 Can cause birth defects
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg351
Drug Class: Direct Renin Inhibitors
 Drug: aliskiren (Tekturna)
 Actions
 Blocks the first step in the RAAS cascade, preventing release of
aldosterone
 Uses
 Alone or in combination with other antihypertensives to reduce
blood pressure
 Not as effective in African Americans, older adults
 Common adverse effects
 Dyspepsia, cramps, diarrhea; headache; orthostatic hypotension
 Serious adverse effects
 Altered fluid and electrolytes, birth defects
Reserved for patients who do not respond to ACE inhibitors or
.
ARBs.
Drug Class: Aldosterone Receptor
Antagonist
pg352
 Drug: eplerenone (Inspra)
 Actions
 Block stimulation of aldosterone at receptor sites, preventing
sodium reabsorption
 Uses
 Alone or in combination with other antihypertensives to reduce
blood pressure, used to treat heart failure
 Common adverse effects
 Nausea, diarrhea; fatigue, headache; orthostatic hypotension
Serious adverse effects: hyperkalemia, hyperlipidemia,
nephrotoxicity, hepatotoxicity, vaginal bleeding,
gynecomastia.
Aldosterone Receptor Antagonist
(cont.)
 Serious adverse effects
 Hyperkalemia
 Elevated lipids
 Nephrotoxicity
 Hepatotoxicity
 Gynecomastia
 Vaginal bleeding
 Numerous drug/food interactions
 Lower dose required for older adults, those with hepatic failure
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg354
Drug Class: Calcium Channel Blockers
 Actions
 Inhibit movement of calcium ions across cell membranes
 Uses
 Ideal for first- or second-line drug therapy for hypertension
 Effective in African-American patients
 Serious adverse effects
 Hypotension and syncope
 Edema
• see Table
227.pg355
• Also used for heart
rhythm disturbances and
angina.
• Effective for African
Americans and elderly
patients.
Drug Class: Alpha-1 Adrenergic
Blocking Agents
pg356
 Actions
 Block postsynaptic alpha-1 adrenergic receptors to produce
vasodilation, decrease peripheral vascular resistance
 Uses
 Alone or in combination with other antihypertensives to reduce
blood pressure
 Reduce mild to moderate urinary obstruction
 Common adverse effects
 Drowsiness, headache, weakness, lethargy; dizziness,
tachycardia, fainting
Copyright © 2017 Elsevier Inc. All Rights Reserved.
Drug Class: Central-Acting Alpha-2
Agonists
pg357
 Actions
 Stimulate alpha-adrenergic receptors in the brainstem, reducing
sympathetic outflow from CNS
 Uses
 Considered adjunctive therapy; used only in combination with other
antihypertensives
 Common adverse effects
 Drowsiness, dry mouth, dizziness, altered urine color, altered rest
results
• Adverse effects such as dry mouth
and dizziness are self-limiting.
 Serious adverse effects
Urine will darken on exposure to
 Depression; rash
air and is not harmful. False-positive
urine glucose tests may occur.
• Rash occurs with transdermal patch
application of clonidine.
Central-Acting Alpha-2 Agonists
 Do not abruptly discontinue clonidine; could cause rebound
effect with increased BP, nervousness, agitation, restlessness,
etc.
 Withdrawal symptoms could appear within a few hours,
become severe in 8 to 24 hours
 Use adhesive overlay to keep patch in place
Copyright © 2017 Elsevier Inc. All Rights Reserved.
pg360
Drug Class: Direct Vasodilators
 Actions
 Relax arterial smooth muscle, reducing peripheral vascular resistance
 Uses
 Treatment of stage 2 hypertension, renal disease hypertension,
toxemia of pregnancy
 Common adverse effects
 Dizziness, numbness, tingling in legs; orthostatic hypotension,
palpitations, tachycardia; nasal congestion; hair growth
 Serious adverse effects
 Fever, chills, joint and muscle pain, skin eruptions; gynecomastia
• Drugs: hydralazine (Apresoline), minoxidil (Loniten), and nitroprusside
sodium (Nitropress)
.
• Nitroprusside is used in severe
hypertensive crisis and refractory heart
failure.