CHAPTER

Used to Treat 23 Drugs Hypertension http://evolve.elsevier.com/Clayton

Chapter Content Hypertension (p. •••) Prevention and Management of Hypertension (p. •••) Drug Therapy for Hypertension (p. •••) Drug Class: Diuretics (p. •••) Drug Class: Beta Adrenergic–Blocking Agents (p. •••) Drug Class: Angiotensin-Converting Enzyme Inhibitors (p. •••) Drug Class: Angiotensin II Receptor Blockers (p. •••) Drug Class: Aldosterone Receptor Antagonist (p. •••) Drug Class: Calcium Ion Antagonists (p. •••) Drug Class: Alpha-1 Adrenergic Blocking Agents (p. •••) Drug Class: Central-Acting Alpha-2 Agonists (p. •••) Drug Class: Peripheral-Acting Adrenergic Antagonists (p. •••) Drug Class: Direct Vasodilators (p. •••)

Objectives 1. Summarize nursing assessments and interventions used for the treatment of hypertension.

2. State recommended lifestyle modifications for a diagnosis of hypertension.

3. Identify 10 classes of drugs used to treat hypertension. 4. Review Figure 23-3 to identify options and progression of treatment for hypertension. 5. Identify specific factors the hypertensive patient can use to assist in managing the disease. 6. Develop patient education objectives for individuals with hypertension. 7. Summarize the action of each drug class used to treat hypertension.

K e y Te r m s arterial blood pressure systolic blood pressure diastolic blood pressure pulse pressure mean arterial pressure (MAP)

cardiac output (CO) hypertension primary hypertension secondary hypertension systolic hypertension

HYPERTENSION (For an introduction to cardiovascular diseases, see Chapter 21.) A primary function of the heart is to circulate blood to the organs and tissues of the body. When the heart contracts (systole) (sis’ tahl e), blood is pumped

out through the pulmonary artery to the lungs and out through the aorta to the other organs and peripheral tissues. The pressure with which the blood is pushed from the heart is referred to as the arterial blood pressure or systolic blood pressure. When the heart muscle relaxes between contractions (diastole) (dy as’ tahl e), the blood pressure drops to a lower level, the diastolic blood pressure. When recorded in the patient’s chart, the systolic pressure is recorded first, followed by the diastolic pressure (e.g., 120/80 mm Hg). The difference between the systolic and diastolic pressure is called the pulse pressure, which is an indicator of the tone of the arterial blood vessel walls. The mean arterial pressure (MAP) is the average pressure throughout each cycle of the heartbeat and is significant because it is the pressure that actually pushes the blood through the circulatory system to perfuse tissue. It is calculated by adding one third of the pulse pressure to the diastolic pressure or by using the following equation: systolic pressure  diastolic pressure diastolic MAP  _________________________________  pressure 3

Under normal conditions, the arterial blood pressure stays within narrow limits. It reaches its peak during high physical or emotional activity and is usually at its lowest level during sleep. Arterial blood pressure (BP) can be defined as the product of cardiac output (CO) and peripheral vascular resistance (PVR): BP  CO  PVR

CO is the primary determinant of systolic pressure; peripheral vascular resistance determines the diastolic pressure. CO is determined by the stroke volume (the volume of blood ejected in a single contraction of the left ventricle), heart rate (controlled by the autonomic nervous system), and venous capacitance (capability of veins to return blood to the heart). Systolic blood pressure is thus increased by factors that increase heart rate or stroke volume. Venous capacitance affects the volume of blood (or preload) that is returned to the heart through the central venous circulation. Venous constriction decreases venous capacitance, increasing preload and systolic pressure, and venous dilation increases venous capacitance and decreases preload and systolic pressure. Peripheral vascular resistance is regulated primarily by contraction and dilation of arteri363

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oles. Arteriolar constriction increases peripheral vascular resistance and thus diastolic blood pressure. Other factors that affect vascular resistance include the elasticity of the blood vessel walls and the viscosity of the blood. Hypertension is a disease characterized by an elevation of the systolic blood pressure, the diastolic blood pressure, or both. Statistics in North America show that blood pressures above 140/90 mm Hg are associated with premature death, which results from accelerated vascular disease of the brain, heart, and kidneys. Primary hypertension accounts for 90% of all clinical cases of high blood pressure. The cause of primary hypertension is unknown. At present, it is incurable but controllable. It is estimated that more than 50 million people in the United States have hypertension. The prevalence increases steadily with advancing age such that people who are normotensive at age 55 have a 90% lifetime risk of developing hypertension. In every agegroup, the incidence of hypertension is higher for African Americans than whites of both sexes. Other major risk factors associated with high blood pressure are listed in Box 23-1. Secondary hypertension occurs after the development of another disorder within the body (Box 23-2). The Seventh Report of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure 2003 (JNC 7) has classified blood pressure by stages that represent the degree of risk of nonfatal and fatal cardiovascular disease events and renal disease

Box 23-1 Major Risk Factors Associated with Hypertension and Target Organ Damage Major Risk Factors Hypertension* Cigarette smoking Obesity* (body mass index 30 kg/m2) Physical inactivity Dyslipidemia* Diabetes mellitus* Microalbuminuria or estimated glomerular filtration rate (GFR) 60 mL/min Age (older than 55 for men, 65 for women) Family history of premature cardiovascular disease (men younger than age 55; women, age 65)

(Table 23-1). The category of “prehypertension” was added to the classification system in the 2003 report 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 with blood pressure in this range are in need of increased education and lifestyle modification to gain control of their blood pressure to prevent cardiovascular disease. The JNC 7 guidelines consider an elevation in both systolic and diastolic blood pressure readings when making a diagnosis of hypertension. The individual should be seated quietly for at least 5 minutes in a chair (rather than an examination table), with feet on the floor, and the arm supported at heart level. An appropriately sized cuff (cuff bladder encircling at least 80% of the arm) should be used for accuracy. A person must have two or more elevated readings on two or more separate occasions after initial screening to be classified as having hypertension. When systolic and diastolic readings fall into two different stages, the higher of the two stages is used to classify the degree of hypertension present. Table 23-2 lists follow-up recommendations based on the initial set of blood pressure measurements. Measurement of blood pressure in the standing position is indicated periodically, especially in those at risk for postural hypotension. In 2000, the Coordinating Committee of the National High Blood Pressure Education Program updated the JNC-VI guidelines and urged health practitioners to use the systolic blood pressure as the major criterion for the diagnosis and management of hypertension in middleaged and older Americans. Prior to this time, the diastolic blood pressure had been the major determinant for the control of blood pressure. Recent evidence indicates that systolic hypertension is the most common form of hypertension and is present in about two thirds of hypertensive individuals older than 60 years of age. When a person has been diagnosed with hypertension, further evaluation through medical history, physical examination, and laboratory tests should be completed to (1) identify causes of the high blood pressure, (2) assess the presence or absence of target organ damage and cardiovascular disease (see Box 23-1), and (3) identify other cardiovascular risk factors that may guide treatment (see Table 23-1).

Target Organ Damage Heart Left ventricular hypertrophy Angina or prior myocardial infarction Prior coronary revascularization Heart failure Brain Stroke or transient ischemic attack Chronic kidney disease Peripheral arterial disease Retinopathy Glomerular filtration rate (GFR) Components of the metabolic syndrome From The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, National Institutes of Health, Publication No. 03-5233, May 2003.

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Box 23-2 Identifiable Causes of Hypertension Sleep apnea Drug-induced or related causes Chronic kidney disease Primary aldosteronism Renovascular disease Chronic steroid therapy and Cushing’s syndrome Pheochromocytoma Coarctation of the aorta Thyroid or parathyroid disease From The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, National Institutes of Health, Publication No. 03-5233, May 2003.

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Table 23-1 Classification and Management of Blood Pressure for Adults* BLOOD PRESSURE (mm Hg)

INITIAL DRUG THERAPY

BP CLASSIFICATION

SYSTOLIC

DIASTOLIC

LIFESTYLE MODIFICATION

WITHOUT COMPELLING INDICATION

WITH COMPELLING INDICATION

Normal

120

and 80

Encourage

Prehypertension

120-139

or 80-89

Yes

Stage 1 hypertension

140-159

or 90-99

Yes

No antihypertensive drug indicated No antihypertensive drug indicated Thiazide-type diuretics for most; may consider ACEI, ARB, BB, CCB, or combination

Stage 2 hypertension

160

or 100

Yes

Drug(s) for compelling indications Drug(s) for compelling indications† Drug(s) for the compelling indications† Other antihypertensive drugs (diuretics, ACEI, ARB, BB, CCB) as needed Drug(s) for the compelling indications Other antihypertensive drugs (diuretics, ACEI, ARB, BB, CCB) as needed

Two-drug combination for most‡ (usually thiazide-type diuretic and ACEI or ARB, or BB, or CCB)

From The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, National Institutes of Health, Publication No. 03-5233, May 2003. *Treatment determined by highest BP category. †Treat patients with chronic kidney disease or diabetes to BP goal of 130/80 mm Hg. ‡Initial combined therapy should be used cautiously in those at risk for orthostatic hypotension. ACEI, Angiotensin-converting enzyme inhibitor; ARB, angiotensin-receptor blocker; BB, beta blocker; CCB, calcium channel blocker.

Table 23-2 Recommended Follow-Up Schedule After Initial Blood Pressure Measurement INITIAL BLOOD PRESSURE (mm Hg)* SYSTOLIC

DIASTOLIC

FOLLOW-UP RECOMMENDED†

130 130-139 140-159 160-179 180

85 85-89 90-99 100-109 110

Recheck in 2 years Recheck in 1 year‡ Confirm within 2 months‡ Evaluate or refer to source of care within 1 month Evaluate or refer to source of care immediately or within 1 week, depending on clinical situation

*If systolic and diastolic categories are different, follow recommendations for shorter time follow-up (e.g., 160/86 mm Hg should be evaluated or referred to source of care within 1 month). †Modify the scheduling of follow-up according to reliable information about past blood pressure measurements, other cardiovascular risk factors, or target organ disease. ‡Provide advice about lifestyle modifications.

TREATMENT OF HYPERTENSION The primary purpose for controlling hypertension is to reduce the frequency of cardiovascular disease (angina, myocardial infarction, heart failure, stroke, renal failure, retinopathy). To accomplish this goal, the blood pressure must be reduced and maintained below 140/90 mm Hg, if possible. Patients who also have conditions such as diabetes mellitus, heart failure, or renal disease should have a goal of less than 130/80 mm Hg. Major lifestyle modifications shown to lower blood pressure include weight reduction in those who are overweight or obese, adoption of the Dietary Approaches to Stop Hypertension (DASH) diet, dietary sodium reduction, physical activity, and moderation of alcohol consumption (Table 23-3). Treatment schedules should interfere as little as possible with the patient’s lifestyle; however, nonpharmacologic therapy must include elimination of smoking, weight control, routine activity, restriction of alcohol intake, stress reduction, and sodium control. If this therapy is successful in controlling high blood pressure, drug ther-

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apy is not necessary. Even if lifestyle changes are not adequate to control hypertension, they may reduce the number and doses of antihypertensive medications needed to manage the condition. Patient education is vitally important in treating hypertension. This education should be emphasized and reiterated frequently by the physician, pharmacist, and nurse. DRUG THERAPY FOR HYPERTENSION Actions Drugs used in the treatment of hypertension can be subdivided into several categories of therapeutic agents based on site of action (Figure 23-1). Clinical studies classify antihypertensive agents into preferred agents (diuretics and beta adrenergic blockers), alternative agents (angiotensin-converting enzyme [ACE] inhibitors, angiotensin II receptor antagonists [ARBs], calcium ion antagonists, and alpha-1 adrenergic blockers), and adjunctive agents (central-acting alpha-2 agonists, periph-

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Table 23-3 Lifestyle Modifications to Manage Hypertension* APPROXIMATE SYSTOLIC BLOOD PRESSURE REDUCTION (RANGE)

MODIFICATION

RECOMMENDATION

Weight reduction Adopt DASH eating plan Dietary sodium reduction Physical activity

Maintain normal body weight (body mass index 18.5-24.9 kg/m2) Consume a diet rich in fruits, vegetables, and low-fat dairy products with a reduced content of saturated and total fat Reduce dietary sodium intake to no more than 100 mmol per day (2.4 g sodium or 6 g sodium chloride) Engage in regular aerobic physical activity such as brisk walking (at least 30 minutes per day, most days of the week) Limit consumption to no more than two drinks (1 oz or 30 ml ethanol [e.g., 24 oz beer, 10 oz wine, or 3 oz 80-proof whiskey]) per day in most men and no more than one drink per day in women and lighter weight persons

Moderation of alcohol consumption

5-20 mm Hg/10 kg weight loss 8-14 mm Hg 2-8 mm Hg 4-9 mm Hg 2-4 mm Hg

From The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, National Institutes of Health, Publication No. 03-5233, May 2003. *For overall cardiovascular risk reduction, stop smoking. The effects of implementing these modifications are dose and time dependent and could be greater for some individuals. DASH, Dietary Approaches to Stop Hypertension.

ALPHA AND BETA ADRENDEERGIC BLOCKING AGENTS Labetalol

Cortex Hypothalamus

Feedback to vasomotor center

Vasomotor center Sympathetic ganglion

Central-acting adrenergic antagonists

Peripheral-acting adrenergic antagonists

ALDOSTERONE RECEPTOR ANTAGONIST Eplerenone

␤-adrenergic receptor blockers Heart in r ele a bit Inh i

␣- and ␤adrenergic blockers

ren

Calcium channel blockers

Angiotensinconverting enzyme − ACE Inhibitors ↓ Angiotensin I Angiotensin II

Decrease constriction

Decrease sodium reabsorption Kidney

CALCIUM CHANNEL (ION) BLOCKERS Amlodipine Nifedipine ALPHA-1 ADRENERGIC BLOCKING AGENTS Prazosin

se

Blood vessel

Diuretics

ANGIOTENSIN-CONVERTING ENZYME INHIBITORS Enalapril Ramipril Lisinopril ANGIOTENSIN II RECEPTOR BLOCKERS Candesartan Irbesartan Valsartan

Baroreceptor reflex Carotid arteries Aortic arch

Direct arterial vasodilators

BETA ADRENERGIC BLOCKING AGENTS Propranolol Metoprolol

Angiotensin II receptor blockers

CENTRALLY-ACTING ALPHA-2 AGONISTS Clonidine PERIPHERALLY-ACTING ADRENERGIC ANTAGONISTS Guanethidine DIRECT VASODILATORS Hydralazine DIURETICS Hydrochlorthiazide 

Representative examples only

FIGURE 23-1 Sites of action of antihypertensive agents. ␤-blockers, beta adrenergic blockers; CCB, calcium channel blockers; ACE, angiotensin-converting enzyme inhibitors; ARB, angiotensin II receptor blocker; ␣1 blockers, alpha-1 adrenergic–blocking agents; central ␣2 agonists, central-acting alpha-2 agonists.

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Drugs Used to Treat Hypertension CHAPTER 23 eral-acting adrenergic antagonists, and direct vasodilators). Both preferred agents and alternative agents can be used alone, or in combination, to treat hypertension, but adjunctive agents should be used only in combination with a preferred or an alternative agent. The guidelines also provide recommendations for specific groups of patients. For example, older patients with isolated systolic hypertension should first be treated with diuretics. Patients with diabetes and high blood pressure should be treated with the ACE inhibitors. Patients who have hypertension and have suffered a myocardial infarction should be treated with a beta adrenergic–blocking agent, and in most cases, an ACE inhibitor. Other studies have demonstrated that if a patient has heart failure, a diuretic and an ACE inhibitor may be beneficial. If a patient has angina pectoris, dihydropyridine calcium ion antagonists (e.g., amlodipine, nifedipine) may be added to other therapy because they have been proven to relieve chest pain and reduce the incidence of stroke. Other combinations of therapy found to be particularly effective are an ACE inhibitor plus a diuretic or calcium ion antagonist, or an ARB plus a diuretic. See individual monographs for mechanisms of action of each class of antihypertensive agent. Uses A key to long-term success with antihypertensive therapy is to individualize therapy for a patient based on demographic characteristics (e.g., age, gender, race), coexisting diseases and risk factors (e.g., migraine headaches, dysrhythmias, angina, diabetes mellitus), previous therapy (what has or has not worked in the past), concurrent drug therapy for other illnesses, and cost. As outlined in Figure 23-2, the JNC 7 recommends that if lifestyle modifications do not lower blood pressure adequately for patients with stage 1 or 2 hypertension, a diuretic or an alternative agent should be the initial treatment of choice. A low dose should be selected to protect the patient from adverse effects, although it may not immediately control the blood pressure. It must be recognized that it may take months to control hypertension adequately while avoiding adverse effects of therapy. If, after 1 to 3 months, the first drug is not effective, the dosage may be increased, another agent from another class may be substituted, or a second drug from another class with a different mechanism of action may be added (Figure 23-3). The guidelines also recommend that if the first drug started was not a diuretic, a diuretic should be initiated as the second drug, if needed, because the majority of patients will respond to a two-drug regimen if it includes a diuretic. In general, most patients with hypertension will require two or more antihypertensive medications to achieve goal blood pressure (140/90 mm Hg, or 130/80 mm Hg for patients who have diabetes or chronic kidney disease). After blood pressure is reduced to the goal level and maintenance doses of medicines are stabilized, it may be appropriate to change a patient’s medication to a combination antihypertensive product to simplify the regimen and enhance

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compliance. See Table 23-4 for a list of the ingredients of antihypertensive combination products. Patients with stage 2 hypertension may require more aggressive therapy with a second or third agent added if control is not achieved by monotherapy in a relatively short time. Patients with an average diastolic blood pressure of greater than 120 mm Hg require immediate therapy and, if significant organ damage is present, may require hospitalization for initial control. Patients who have modified their lifestyles with appropriate exercise, diet, weight reduction, and control of hypertension for at least 1 year may be candidates for “step-down” therapy. The dosage of antihypertensive medications may be gradually reduced in a slow, deliberate manner. Most patients may still require some therapy, but occasionally, the medicine can be discontinued. Patients whose drugs have been discontinued should have regular follow-up examination because blood pressure often rises again to hypertensive levels, sometimes months or years later, especially if lifestyle modifications are not continued.

NURSING PROCESS for Hypertensive Therapy Assessment History of Risk Factors

• Make note of patient’s gender, age, and race. People who are older, male, and of the African American race have a higher incidence of hypertension. • Has the client been told previously about the elevated blood pressure readings? If so, under what circumstances were the blood pressure readings taken? • Is there a family history of hypertension, coronary heart disease, stroke, diabetes mellitus, or dyslipidemia? Smoking. Obtain a history of the number of cigarettes or cigars smoked daily. How long has the person smoked? Has the person ever tried to stop smoking? Ask if the person knows what effect smoking has on the vascular system. How does the individual feel about modifying the smoking habit? Dietary Habits. Obtain a dietary history. Ask specific questions to obtain data relating to the amount of salt used in cooking and at the table, as well as foods eaten that are high in fat, cholesterol, refined carbohydrates, and sodium. Using a calorie counter, ask the person to estimate the number of calories eaten per day. How much meat, fish, and poultry are eaten daily (size and number of servings)? Estimate the percent of total daily calories provided by fats. Discuss food preparation (e.g., baked, broiled, fried foods). How many servings of fruits and vegetables are eaten daily? What types of oils/fats are used in food preparation? See a nutrition text for further dietary history questions. What is the frequency and volume of alcoholic beverages consumed? Elevated Serum Lipids. Ask whether the patient is aware of having elevated lipids, triglycerides, or cho-

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Lifestyle modifications

Not at goal blood pressure (140/90 mm Hg) (130/80 mm Hg for patients with diabetes or chronic kidney disease)

Initial drug choices

Without compelling indications

With compelling indications

Stage 1 hypertension (SBP 140–159 or DBP 90–99 mm Hg)

Stage 2 hypertension (SBP 160 or DBP 100 mm Hg)

Thiazide-type diuretics for most. Many consider ACEI, ARB, BB, CCB, or combination.

Two-drug combination for most (usually thiazide-type diuretic and ACEI, or ARB, or BB, or CCB)

Drug(s) for the compelling indications Other antihypertensive drugs (e.g., diuretics, ACEI, ARB, BB, CCB) as needed

Not at goal blood pressure

Optimize dosages or add additional drugs until goal blood pressure is achieved. Consider consultation with hypertension specialist. DBP, Diastolic blood pressure; SBP, systolic blood pressure Drug abbreviations: ACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor blocker; BB, beta-blocker; CCB, calcium channel blocker.

FIGURE 23-2 Treatment algorithm for hypertension.

lesterol. If elevated, what measures has the person tried for reduction and what effect have the interventions had on the blood levels at subsequent examinations? Review laboratory data available (e.g., cholesterol, triglycerides, low-density lipoprotein [LDL], very low-density lipoprotein [VLDL]). Renal. Has the patient had any laboratory tests to evaluate renal function (e.g., urinalysis: microalbuminuria, proteinuria, microscopic hematuria) or blood analysis showing an elevated blood urea nitrogen

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(BUN) or serum creatinine? Does the patient have nocturia? Obesity. Weigh and measure the patient. Measure the waist circumference 2 inches above the navel. Ask about any recent weight gains or losses and whether intentional or unintentional. Note abnormal waist-hip ratio. Psychomotor Functions

• Determine type of lifestyle. Ask the patient to describe exercise level in terms of amount (walking 3 miles), intensity (walking 3 mph), and fre-

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Blood pressure

Cardiac output

Heart rate

Peripheral vascular resistance

Stroke volume

-blockers CCB

Contractility

Nerve transmission

Circulating regulators

Local regulators

1-blockers Central 2-agonists

1-blockers Central 2-agonists ACE inhibitors ARBs

ACE inhibitors ARBs Nitroprusside

Direct vasodilators

Preload

-blockers CCB

CCBs Nitroprusside Minoxidil Hydralazine Venous tone

Vascular volume

1-blockers ACE inhibitors ARBs Nitroprusside

Sodium/water retention Diuretics ACE inhibitors ARBs

FIGURE 23-3 Effects of antihypertensive agents.

quency (walking every other day). Is the patient’s job physically demanding or of a sedentary nature? • Determine psychological stress. How much stress does the individual estimate having in life? How does the person cope with stressful situations at home and in the workplace? • Has the client experienced any fatigue or reduction in activity level due to intolerance or palpitations, angina, or dyspnea? When walking, does the individual experience severe leg cramps (claudication) that force him/her to stop and rest or to severely limit ambulation? Medication History

• Has the patient ever taken or is the patient currently taking any medications for the treatment of high blood pressure? If blood pressure medications have been prescribed but are not being taken, why was the medicine discontinued? Were any side effects noticed while receiving the medications, and how did the patient manage them? • Obtain a listing of all medications being taken, including prescribed, over-the-counter, herbal preparations, and street drugs. Research these medications in the drug monographs to determine potential drug-to-drug interactions that may affect the individual’s blood pressure or the effectiveness of the medicines prescribed.

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• If the patient is female, ask if she is now or has been taking oral contraceptives or is receiving hormone replacement therapy (HRT). Physical Assessments

Blood Pressure. Obtain two or more blood pressure measurements. • The individual should be seated quietly for at least 5 minutes in a chair with back supported (rather than an examination table), with feet on the floor, and arm supported at heart level. • An appropriately sized cuff (cuff bladder encircling at least 80% of the arm) should be used for accuracy. • When measuring blood pressure, the cuff should be inflated to 30 mm Hg above the point at which the radial pulse disappears. The sphygmomanometer pressure should then be reduced at 2 to 3 mm/second. Two readings should be performed at least 1 minute apart. • Verify the readings in the opposite arm. A difference in blood pressure between the two arms can be expected in about 20% of patients. The higher value should be the one used in treatment decisions. • People must have two or more elevated readings on two or more separate occasions after initial screening to be classified as having hypertension. • Orthostatic hypotension is defined by a decrease in systolic blood pressure of 20 mm Hg

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Drug Table 23-4 COMBINATION DRUGS FOR HYPERTENSION COMBINATION TYPE

FIXED-DOSE COMBINATION (mg)*

TRADE NAME

ACEIs and CCBs

amlodipine/benazepril hydrochloride (2.5/10, 5⁄10, 5⁄20, 10/20) enalapril maleate/felodipine (5/2.5,5/5) trandolapril/verapamil (2/180, 1⁄240, 2⁄240, 4⁄240)

Lotrel Lexxel Tarka

CCBs and statin

amlodipine/atorvastatin (2.5/10 to 10/80)

Caduet

ACEIs and diuretics

benazepril/hydrochlorothiazide (5/6.25, 10/12.5, 20/12.5, 20/25) captopril/hydrochlorothiazide (25/15, 25/25, 50/15, 50/25) enalapril maleate/hydrochlorothiazide (5/12.5, 10/25) lisinopril/hydrochlorothiazide (10/12.5, 20/12.5, 20/25) moexipril HCl/hydrochlorothiazide (7.5/12.5, 15/12.5, 15/25) quinapril HCl/hydrochlorothiazide (10/12.5, 20/12.5, 20/25)

Lotensin HCT Capozide Vaseretic Prinzide Uniretic Accuretic

ARBs and diuretics

candesartan cilexetil/hydrochlorothiazide (16/12.5, 32/12.5) eprosartan mesylate/hydrochlorothiazide (600/12.5, 600/25) irbesartan/hydrochlorothiazide (150/12.5, 300/12.5, 300/25) losartan potassium/hydrochlorothiazide (50/12.5, 100/25) telmisartan/hydrochlorothiazide (40/12.5, 80/12.5, 80/25) valsartan hydrochlorothiazide (80/12.5, 160/12.5, 160/25)

Atacand HCT Teveten/HCT Avalide Hyzaar Micardis/HCT Diovan/HCT

BBs and diuretics

atenolol/chlorthilidone (50/25, 100/25) bisoprolol fumarate/hydrochlorothiazide (2.5/6.25, 5⁄6.25, 10/6.25) propranolol LA/hydrochlorothiazide (40/25) metoprolol tartrate/hydrochlorothiazide (50/25, 100/25) nadolol/bendrofluthiazide (40/5, 80/5) timolol maleate/hydrochlorothiazide (10/25)

Tenoretic Ziac Inderide Lopressor HCT Corzide Timolide

Central-acting drug and diuretic

methyldopa/hydrochlorothiazide (250/15, 250/25, 500/30, 500/50) reserpine/chlorothiazide (0.125/250, 0.125/500) reserpine/hydrochlorothiazide (0.125/25, 0.125/50)

Aldoril

Diuretic and diuretic

amiloride HCl/hydrochlorothiazide (5/50) spironolactone/hydrochlorothiazide (25/25, 50/50) triamterene/hydrochlorothiazide (37.5/25, 50/25, 75/50)

Moduretic Aldactazide Dyazide, Maxzide

From The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, National Institutes of Health, Publication No. 03-5233, May 2003. *Some drug combinations are available in multiple fixed doses. Each drug dose is reported in milligrams. ACEI, Angiotensin-converting enzyme inhibitor; ARB, angiotensin-receptor blocker; BB, beta blocker; CCB, calcium channel blocker.

or more, or diastolic blood pressure of 10 mm Hg or more after 3 minutes of quiet standing. Food ingestion, time of day, age, and hydration can affect this form of hypotension, as can a history of parkinsonism, diabetes, or multiple myeloma. • Ensure that the patient has not ingested caffeine within the past 2 to 3 hours. Height and Weight. Weigh and measure the patient. What has the person’s weight been? Ask about any recent weight gains or losses and whether intentional or unintentional. Calculate the body mass index (BMI) (see Chapter 21 for more discussion and classification of BMI): Weight (in kilograms) ____________________________  BMI (kg/m2) Height (in square meters [m2]) or Weight (in pounds) ___________________________  703  BMI (lb/in2) Height (in square inches [in2])

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Bruits. Check neck, abdomen, and extremities for the presence of bruits. Peripheral Pulses. Palpate and record femoral, popliteal, and pedal pulses bilaterally. Eyes. As appropriate to the level of education, perform a funduscopic examination of interior eye, noting arteriovenous nicking, hemorrhages, exudates, or papilledema. Nursing Diagnoses • Knowledge, deficient, related to hypertension (indication) • Noncompliance with drug therapy (indication, side effects) • Sexual dysfunction (side effects) Planning History of Risk Factors

• Examine data to determine the individual’s extent of understanding of hypertension and its control.

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Drugs Used to Treat Hypertension CHAPTER 23 • Using the patient’s history, analyze lifestyle elements to determine health teaching needs of the individual and significant others. Medication History

Plan patient education needed to implement or reinforce prescribed medication therapy. Physical Assessment Schedule physical assessments at specific intervals as appropriate to the patient’s status and clinical site policies (e.g., vital signs taken every 4 hours or 8 hours; intake and output, daily weights). Baseline and Diagnostic Studies. Review the chart and reports available that are used to build baseline information (e.g., electrocardiogram; urinalysis; blood glucose and hematocrit, serum potassium, creatinine and calcium levels; a lipid profile [total cholesterol, LDL cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides] after a 9- to 12-hour fast). Implementation • Perform nursing assessments on a scheduled basis. • Make referrals as indicated for stress management, smoking cessation, and dietary counseling and for an exercise program appropriate for the individual’s needs. • When initiating antihypertensive therapy in the hospitalized patient, protect from possible falls secondary to hypotension by assisting during ambulation and carefully assessing for faintness. Take blood pressure in supine, sitting, and standing positions to identify hypotensive responses.

Patient Education and Health Promotion Smoking. Suggest that the patient stop smoking. Explain the increased risk of coronary artery disease if the habit is continued. It may be necessary to settle for a drastic decrease in smoking in some people, although abstinence should be the goal. Nutritional Status. Dietary counseling is essential in the treatment of hypertension. Control of obesity alone may be sufficient to alter the hypertensive condition. Most patients are placed on a reduced-sodium diet (2.3 g sodium or