Chapter 44 Antihypertensives Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Renin-Angiotensin System Hypertension Selected regulators of blood pressure Kidneys via renin-angiotensin system Renin-Angiotensin System Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Regulators of Blood Pressure Baroreceptors in the aorta and carotid sinus Vasomotor center in the medulla Hormones: antidiuretic hormone (ADH), atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Physiologic Risk Factors Excessive intake of saturated fat and simple carbohydrates Alcohol: increases renin secretions Cultural responses to antihypertensive agents African Americans Asian Americans Hypertension in older adults Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Guidelines for Determining Hypertension Category Systolic Pressure Diastolic Pressure Normal Less than 120 mm Hg Less than 80 mm Hg Prehypertension 120 to 139 mm Hg 80 to 89 mm Hg Stage 1 hypertension 140 to 159 mm Hg 90 to 99 mm Hg Stage 2 hypertension Greater than 160 mm Hg Greater than 100 mm Hg Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Antihypertensive Drugs Diuretics Thiazides: hydrochlorothiazide Loop (high-ceiling) diuretics: furosemide (Lasix) Combinations of hydrochlorothiazide with potassium-sparing diuretics and other antihypertensive drugs (e.g., ACE inhibitors) Side effects Potassium loss or hypokalemia and others Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Sympatholytics (Sympathetic Depressants) Beta-adrenergic blockers Nonselective beta blockers: propranolol (Inderal) and carvedilol (Coreg) Selective beta blockers: acebutolol (Sectral), atenolol (Tenormin), betaxolol (Kerlone), bisoprolol (Zebeta), and metoprolol (Lopressor) Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Beta-Adrenergic Blockers for Hypertension Noncardioselective beta blockers Contraindications: chronic obstructive pulmonary disease (COPD) Cardioselective beta blockers Contraindications: patients with diabetes mellitus when taking beta blockers Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Beta-Adrenergic Blockers for Hypertension (cont.) Side effects Marked decrease in blood pressure, insomnia, depression, nightmares, sexual dysfunction Nursing interventions Do not abruptly stop taking beta blockers: rebound hypertension may result. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Nursing Process: Beta-Adrenergic Blockers Assessment Nursing diagnoses Planning Nursing interventions Patient teaching Cultural considerations Evaluation Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Sympatholytics (Sympathetic Depressants) (cont.) Centrally acting alpha2 agonists: methyldopa, clonidine, guanabenz, and guanfacine Contraindications Impaired liver function Side effects Sodium and water retention, dry mouth, bradycardia Diuretics are frequently prescribed to avoid fluid retention. Avoid abruptly stopping drug. Rebound hypertension may result. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Sympatholytics (Sympathetic Depressants) (cont.) Alpha-adrenergic blockers Action Block the alpha-adrenergic receptors, resulting in vasodilation and decreased blood pressure Drugs Doxazosin (Cardura) Prazosin HCl (Minipress) Terazosin HCL (Hytrin) Side effects: orthostatic hypotension, nausea, headache, drowsiness, nasal congestion caused by vasodilation, edema, and weight gain Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Sympatholytics (Sympathetic Depressants) (cont.) Adrenergic neuron blockers (peripherally acting sympatholytics) Block norepinephrine release from the sympathetic nerve endings, decrease in norepinephrine release, result lower BP Reserpine Side effects: Orthostatic hypotension Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Sympatholytics (Sympathetic Depressants) (cont.) Alpha1- and beta1-adrenergic blockers Labetalol (Normodyne) Carteolol (Cartrol) Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Nursing Process: Alpha- Adrenergic Blockers Assessment Nursing diagnoses Planning Nursing interventions Patient teaching Cultural considerations Evaluation Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Direct-Acting Arteriolar Vasodilators Relaxing the smooth muscles of the blood vessels, mainly the arteries, causing vasodilation Hydralazine Minoxidil Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Angiotensin-Converting Enzyme (ACE) Inhibitors Action Examples Benazepril (Lotensin), captopril (Capoten), enalapril maleate (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace), and trandolapril (Mavik), captopril (Capoten) Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Angiotensin-Converting Enzyme (ACE) Inhibitors (cont.) African-American adults and older adults Do not respond with ACEI monotherapy Do respond when taken with diuretic Side effects Irritating cough, insomnia, hyperkalemia, tachycardia Contraindications Pregnancy Potassium-sparing diuretics such as spironolactone (Aldactone) Salt substitutes that contain potassium Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Angiotensin II Receptor Blockers (ARBs) Action Examples Losartan (Cozaar), valsartan (Diovan), irbesartan (Avapro), candesartan cilexetil (Atacand), eprosartan (Teveten), olmesartan medoxomil (Benicar), and telmisartan (Micardis) are examples of ARBs. Less likely to cause irritating cough Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Direct Renin Inhibitor Action Example Aliskiren (Tekturna) Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Calcium Channel Blockers Action Decrease calcium levels and promote vasodilation Examples Diphenylalkylamine (verapamil), benzothiazepines (diltiazem), and dihydropyridine (amlodipine and others) Side effects/adverse reactions Flush, headache, dizziness, ankle edema, bradycardia, and AV block Refer to Table 44-4, Antihypertensives: Calcium Channel Blockers. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #1 A patient’s blood pressure (BP) is 142/82 mm Hg. The health care provider prescribed a diuretic to lower this BP. The nurse knows that this BP is within the prehypertensive range. indicating stage 1 hypertension. indicating stage 1 hypertension according to the diastolic pressure. indicating stage 2 hypertension according to the new guidelines for hypertension. Answer: B Rationale: A BP of 142/82 indicates stage 1 hypertension. The systolic range for stage 1 is 140 to 159, and the diastolic range for stage 1 is 90 to 99. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #2 A patient is receiving an angiotensin II receptor blocker (ARB). Which does the nurse recognize as an ARB? Valsartan (Diovan) Amlodipine (Norvasc) Captopril (Capoten) Metoprolol (Lopressor) Answer: A Rationale: ARBs have a suffix of -sartan. Valsartan (Diovan) is an ARB. Amlodipine is a calcium channel blocker; captopril is an ACE inhibitor with a common suffix of -pril. Metoprolol is a beta blocker with a common suffix of -lol. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #3 A patient is receiving an angiotensin II receptor blocker. It is most important for the nurse to assess the patient for constipation. tremors. asthmatic attacks. dizziness. Answer: D Rationale: Side effects/adverse effects of ARBs include dizziness, diarrhea, insomnia, occasional cough, and upper respiratory infection. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #4 An African-American patient is to be treated with initial monotherapy to control hypertension. The nurse expects the patient to receive A. diuretics. B. angiotensin-converting enzyme inhibitors. C. alpha-adrenergic blockers. D. beta blockers. Answer: C Rationale: African Americans do not respond well to diuretics as the initial monotherapy for controlling hypertension. This group is susceptible to low-renin hypertension; therefore, they do not respond well to beta blockers and ACE inhibitors. The antihypertensive drugs that are effective for African Americans are alpha1 blockers and calcium channel blockers. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #5 The nurse should instruct a patient to not suddenly stop taking antihypertensives in order to avoid rebound bradycardia. rebound tachycardia. rebound hypertension. rebound hypotension. Answer: C Rationale: Abrupt discontinuation of antihypertensive drugs may cause rebound hypertension. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #6 A patient with hypertension is ordered to receive an ACE inhibitor. The nurse identifies a common benign side effect of this class of medications as hiccups. flatulence. abdominal distention. a dry cough. Answer: D Rationale: The primary side effect of ACE inhibitors is a constant, irritated cough. Other side effects include nausea, vomiting, diarrhea, headache, dizziness, fatigue, insomnia, serum potassium excess, and tachycardia. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #7 Before administering the alpha-adrenergic blocker prazosin (Minipress), it is most important for the nurse to assess the patient for a history of renal disease. refractory heart failure. hypertension. benign prostatic hypertrophy. Answer: A Rationale: Prazosin (Minipress) is used to treat refractory heart failure, hypertension, and benign prostatic hypertrophy. Contraindication to use of the drug is renal disease. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.

Practice Question #8 When administering antihypertensive medications to Asian Americans, it is most important for the nurse to increase the dose of beta blockers. monitor blood pressure carefully. expect to administer the usual dose antihypertensive medications. understand that this cultural group does not believe in treating hypertension. Answer: B Rationale: Asian Americans are twice as sensitive as whites to beta blockers and other antihypertensives. A reduction in antihypertensive dosing is frequently needed. Native Americans have a reduced or lower response to beta blockers compared with whites. Monitoring blood pressure and drug dosing should be an ongoing assessment for these cultural groups. Copyright © 2015, 2012, 2009, 2006, 2003, 2000, 1997, 1993 by Saunders, an imprint of Elsevier Inc.