Timby/Smith: Introductory Medical-Surgical Nursing, 11/e Chapter 27: Caring for Clients With Hypertension

Physiology of Blood Pressure Blood pressure (BP) is the force produced by the volume of blood in arterial walls. BP = CO (cardiac output) x PR (peripheral resistance) Measuring BP reflects The ability of the arteries to stretch and fill with blood The efficiency of the heart as a pump The volume of circulating blood BP is affected by age, body size, diet, activity, emotions, pain, position, gender, time of day, and disease states.

Physiology of Blood Pressure—(cont.) BP measure with standard sphygmomanometer and stethoscope BP expressed as a fraction: top number: systolic BP; bottom number: diastolic BP Normal BP for adults: ranges from 100/60 to 119/79 mm Hg Autonomic nervous system, kidneys, and various endocrine glands regulate arterial pressure. BP usually increases with age due to arteriosclerotic and atherosclerotic changes in blood vessels or other effects of chronic diseases. Example: diabetes, renal dysfunction

Systolic Blood Pressure Systolic BP: determined by force and volume of blood that the left ventricle ejects during systole and the ability of the arterial system to distend at the time of ventricular contraction Older patients may have elevated systolic BP; arteriosclerosis Arteriosclerosis causes vasoconstriction, which increases peripheral resistance, which in turn increases systolic BP.

Diastolic Blood Pressure Diastolic BP: arterial pressure during ventricular relaxation Resistance of the arterioles and diastolic filling times; if arterioles are constricted, blood is under greater pressure Central aortic systolic pressure (CASP) The pressure of blood at the root of the aorta as blood is pumped from the left ventricles Measured invasively by passing a catheter from femoral artery to aorta or by a CASPro computerized monitor

Question The nurse is educating clients at the community center on the risk factors of developing hypertension. Which of the following is considered at the highest risk for developing hypertension? A) Obese adults B) Older adults with diabetes C) Adults who exercise twice weekly D) Older adults with glaucoma

Answer B) Older adults with diabetes Rationale: Screening of BP is an important method for identifying people at risk for heart failure, renal failure, and stroke. Those at highest risk are older adults, African American, and clients with diabetes mellitus.

Hypertensive Disease Hypertension: high blood pressure Risks: heart disease, heart failure, stroke, kidney disease Prehypertension: systolic BP between 120 and 139 mm Hg and diastolic BP between 80 and 89 mm Hg Stage 1 hypertension: systolic BP of 140 to 159 mm Hg or diastolic BP between 90 and 99 mm Hg Stage 2 hypertension: systolic BP that equals or exceeds 160 mm Hg or diastolic BP that equals or exceeds 100 mm Hg

Hypertensive Disease—(cont.) Hypertensive heart disease: elevated BP causes a cardiac abnormality Types Hypertensive vascular disease: vascular damage is present without heart involvement Hypertensive cardiovascular disease: both heart disease and vascular damage accompany hypertension

Hypertensive Disease—(cont.) Categories Essential hypertension: primary, idiopathic Ninety-five percent of cases: sustained elevated BP with no known cause Secondary hypertension: elevated BP results from or is secondary to some other disorder White-coat hypertension: elevated BP that develops during evaluation by medical personnel

Hypertensive Disease—(cont.) Essential Hypertension Causes: unknown, age, familial, African Americans Risk factors: obesity, inactivity, smoking, alcohol, ineffective stress management; hypernatremia, alterations in body chemicals, impairment in renin-angiotensin-aldosterone mechanism Secondary Hypertension Causes: accompany any primary conditions that affect fluid volume or renal function Risk factors: kidney disease, pheochromocytoma, hyperaldosteronism, atherosclerosis, cocaine use, cardiac stimulants, oral contraceptives

Hypertensive Disease—(cont.) Assessment Findings General: throbbing or pounding headache, dizziness, fatigue, insomnia, nervousness, nosebleeds Size of heart muscle increases; heart failure Myocardial ischemia: myocardial infarction, angina, dyspnea Hemorrhage of tiny arteries in eyes; blurred vision, papilledema Cerebrovascular accident Renal failure

Hypertensive Disease—(cont.) Diagnostic Findings Electrocardiography, echocardiography, chest radiography: enlarged left ventricle Multiple gated acquisition (MUGA) scan: detects inefficiently the heart pumps Blood tests Elevated blood urea nitrogen, serum creatinine levels Intravenous pyelography (IVP), fluorescein angiography, ophthalmologic test using IV dye, renal arteriography, 24-hour collected urine specimen

Hypertensive Disease—(cont.) Medical Management Nonpharmacological interventions used for clients with prehypertension Weight reduction, decreased sodium intake, moderate exercise, reducing smoking and alcohol use Drug therapy: treatment depends on stage; thiazide diuretic; most people need two or more antihypertensive medications to reduce BP; if BP remains elevated, a third or fourth antihypertensive agent may be added.

Question Which condiment would the nurse recommend to a client with hypertension who is on a low-sodium diet? A) Catsup B) Lemon juice C) Garlic salt D) Soy sauce

Answer B) Lemon juice Rationale: Lemon juice represents the only choice that has no sodium; all of the other choices are high in sodium content.

Hypertensive Disease—(cont.) Nursing Management BP in both arms initially with client in supine, sitting, and then standing position Questions about client following treatment regimen, additional cardiac assessments, medical history, and current symptoms Nonpharmacologic and pharmacologic methods for restoring and maintaining BP Techniques for self-management, collaborate with dietitian, DASH diet

Accelerated and Malignant Hypertension Develops in clients with essential or secondary hypertension Accelerated hypertension: markedly elevated BP accompanied by hemorrhages and exudates in the eyes Malignant hypertension: untreated accelerated hypertension Dangerously elevated BP accompanied by papilledema

Accelerated and Malignant Hypertension—(cont.) Pathophysiology and Etiology: occur in clients with undiagnosed hypertension or those who fail to follow up or comply with medical therapy Abrupt onset; if untreated, severe symptoms and complications follow rapidly Malignant hypertension is fatal unless BP is quickly reduced. Kidneys, brain, and heart may be permanently damaged; arterial blood vessels may rupture or will soon; retinal hemorrhages may lead to blindness; stroke can occur; aneurysm may burst and cause hemorrhage and shock; pulmonary edema or MI, renal failure

Accelerated and Malignant Hypertension—(cont.) Assessment Findings: confusion, headache, visual disturbances, seizures, coma Rise in BP may cause chest pain, dyspnea, moist lung sounds; renal failure Severe back pain accompanied by hypotension; aortic aneurysm is dissecting or ruptured Systolic BP is 160 mm Hg or higher, diastolic BP is 100 mm Hg or higher or both, optic nerve appears to bulge forward, retinal blood vessels are obscured

Accelerated and Malignant Hypertension—(cont.) Medical Management Goal is to lower BP within 1 to 2 hours IV drugs: diazoxide (Hyperstat IV), nitroprusside (Nitropress), nitroglycerin, labetalol (Normodyne) Oral medications for less critical clients: nifedipine (Procardia), verapamil (Isoptin), captopril (Capoten), prazosin (Minipress) Oxygen to reduce hypoxia-induced tachycardia

Accelerated and Malignant Hypertension—(cont.) Nursing Management Implements medical orders promptly, mixes drugs with IV solution after carefully calculating the dosage, checks the site and progress of infusion at least hourly, automatic BP recording machine Reports systolic BP of 160 mm Hg or higher or a diastolic BP of 115 mm Hg or higher immediately; restricts client activity; monitors for neurologic, cardiac, and renal complications Keeps emergency equipment and drugs ready in case of complications

Question A 38-year-old man has hypertension. He is interested in starting an exercise program. What form of exercise would be best for him? A) Bicycling B) Water skiing C) Weight lifting D) Calisthenics

Answer A) Bicycling Rationale: Bicycling represents the only isotonic (dynamic) exercise, which is the form recommended for hypertensive clients.