GENDER CUE:Hypertension has been reported to be two to three times more common in women taking hormonal contraceptives than those not taking them. Women age 35 and older who smoke cigarettes should be strongly encouraged to stop; if they continue to smoke, they should be discouraged from using hormonal contraceptives.
Elevated blood pressure may develop suddenly or gradually. A sudden, severe rise in pressure (exceeding 180/110 mm Hg) may indicate life-threatening hypertensive crisis. However, even a less dramatic rise may be equally significant if it heralds a dissecting aortic aneurysm, increased intracranial pressure, myocardial infarction, eclampsia, or thyrotoxicosis.
Usually associated with essential hypertension, elevated blood pressure may also result from a renal or endocrine disorder; a treatment that affects fluid status, such as dialysis; or a drug's adverse effect. Ingestion of large amounts of certain foods, such as black licorice and cheddar cheese, may temporarily elevate blood pressure. (See Pathophysiology of elevated blood pressure.)
Sometimes, elevated blood pressure may simply reflect inaccurate blood pressure measurement. (See Ensuring accurate blood pressure measurement, page 83.) However, careful measurement alone doesn't ensure a clinically useful reading. To be useful, each blood pressure reading must be compared with the patient's baseline. Also, serial readings may be necessary to establish elevated blood pressure.
History and physical examination
If you detect sharply elevated blood pressure, quickly rule out possible life-threatening causes. (See Managing elevated blood pressure.)
After ruling out life-threatening causes, complete a more leisurely history and physical examination. Determine if the patient has a history of cardiovascular or cerebrovascular disease, diabetes, or renal disease. Ask about a family history of high blood pressure — a likely finding with essential hypertension, pheochromocytoma, or polycystic kidney disease. Then ask about its onset. Did high blood pressure appear abruptly? Ask the patient's age. The sudden onset of high blood pressure in middle-aged or elderly patients suggests renovascular stenosis. Although essential hypertension may begin in childhood, it typically isn't diagnosed until near age 35. Pheochromocytoma and primary aldosteronism usually occur between ages 40 and 60. If you suspect either, check for orthostatic hypotension. Take the patient's blood pressure with him lying down, sitting, and then standing. Normally, systolic pressure falls and diastolic pressure rises on standing. With orthostatic hypotension, both pressures fall.
Note headache, palpitations, blurred vision, and sweating. Ask about wine-colored urine and decreased urine output; these signs suggest glomerulonephritis, which can cause elevated blood pressure.
Obtain a drug history, including past and present prescriptions, herbal preparations, and over-the-counter drugs (especially decongestants). If the patient is already taking an antihypertensive, determine how well he complies with the regimen. Ask about his perception of elevated blood pressure. How serious does he believe it is? Does he expect drug therapy to help? Explore psychosocial or environmental factors that may impact blood pressure control.
Follow up the history with a thorough physical examination. Using a funduscope, check for intraocular hemorrhage, exudate, and papilledema, which characterize severe hypertension. Perform a thorough cardiovascular assessment. Check for carotid bruits and jugular vein distention. Assess skin color, temperature, and turgor. Palpate peripheral pulses. Auscultate for abnormal heart sounds (gallops, louder second sound, murmurs), rate (bradycardia, tachycardia), or rhythm. Then auscultate for abnormal breath sounds (crackles, wheezing), rate (bradypnea, tachypnea), or rhythm.
Palpate the abdomen for tenderness, masses, or liver enlargement. Auscultate for abdominal bruits. Renal artery stenosis produces bruits over the upper abdomen or in the costovertebral angles. Easily palpable, enlarged kidneys and a large, tender liver suggest polycystic kidney disease. Obtain a urine sample to check for microscopic hematuria.
Medical causes
❑ Anemia. Accompanying elevated systolic pressure in anemia are pulsations in the capillary beds, bounding pulse, tachycardia, systolic ejection murmur, pale mucous membranes and, in patients with sickle cell anemia, ventricular gallop and crackles.❑ Aortic aneurysm (dissecting). Initially, this life-threatening disorder causes a sudden rise in systolic pressure (which may be the precipitating event), but no change in diastolic pressure. However, this increase is brief. The body's ability to compensate fails, resulting in hypotension.
Other signs and symptoms vary, depending on the type of aortic aneurysm. An abdominal aneurysm may cause persistent abdominal and back pain, weakness, sweating, tachycardia, dyspnea, a pulsating abdominal mass, restlessness, confusion, and cool, clammy skin. A thoracic aneurysm may cause a ripping or tearing sensation in the chest, which may radiate to the neck, shoulders, lower back, or abdomen; pallor; syncope; blindness; loss of consciousness; sweating; dyspnea; tachycardia; cyanosis; leg weakness; murmur; and absent radial and femoral pulses.
❑ Atherosclerosis. With atherosclerosis, systolic pressure rises while diastolic pressure commonly remains normal or slightly elevated. The patient may show no other signs, or he may have a weak pulse, flushed skin, tachycardia, angina, and claudication.
❑ Cushing's syndrome. Twice as common in females as in males, Cushing's syndrome causes elevated blood pressure and widened pulse pressure as well as truncal obesity, moon face, and other cushingoid signs. It's usually caused by corticosteroid use.
❑ Hypertension. Essential hypertension develops insidiously and is characterized by a gradual increase in blood pressure from decade to decade. Except for this high blood pressure, the patient may be asymptomatic or (rarely) may complain of suboccipital headache, light-headedness, tinnitus, and fatigue.
With malignant hypertension, diastolic pressure abruptly rises above 120 mm Hg, and systolic pressure may exceed 200 mm Hg. Typically, the patient has pulmonary edema marked by jugular vein distention, dyspnea, tachypnea, tachycardia, and coughing of pink, frothy sputum. Other characteristic signs and symptoms include severe headache, confusion, blurred vision, tinnitus, epistaxis, muscle twitching, chest pain, nausea, and vomiting.
❑ Increased intracranial pressure (ICP). Increased ICP causes an increased respiratory rate initially, followed by increased systolic pressure and widened pulse pressure. Increased ICP affects the heart rate last, causing bradycardia (Cushing's reflex). Associated signs and symptoms include headache, projectile vomiting, a decreased level of consciousness, and fixed or dilated pupils.
❑ Myocardial infarction (MI). MI is a life-threatening disorder that may cause high or low blood pressure. Common findings include crushing chest pain that may radiate to the jaw, shoulder, arm, or epigastrium. Other findings include dyspnea, anxiety, nausea, vomiting, weakness, diaphoresis, atrial gallop, and murmurs.
❑ Pheochromocytoma. Paroxysmal or sustained elevated blood pressure characterizes pheochromocytoma and may be accompanied by orthostatic hypotension. Associated signs and symptoms include anxiety, diaphoresis, palpitations, tremors, pallor, nausea, weight loss, and headache.
❑ Polycystic kidney disease. Elevated blood pressure is typically preceded by flank pain. Other signs and symptoms include enlarged kidneys; an enlarged, tender liver; and intermittent gross hematuria.
❑ Preeclampsia and eclampsia. Potentially life-threatening to the mother and fetus, preeclampsia and eclampsia characteristically increase blood pressure. They're defined as a reading of 140/90 mm Hg or more in the first trimester, a reading of 130/80 mm Hg or more in the second or third trimester, an increase of 30 mm Hg above the patient's baseline systolic pressure, or an increase of 15 mm Hg above the patient's baseline diastolic pressure. Accompanying elevated blood pressure are generalized edema, sudden weight gain of 3 lb (1.4 kg) or more per week during the second or third trimester, severe frontal headache, blurred or double vision, decreased urine output, proteinuria, midabdominal pain, neuromuscular irritability, nausea, and possibly seizures (eclampsia).
❑ Renovascular stenosis. Renovascular stenosis produces abruptly elevated systolic and diastolic pressures. Other characteristic signs and symptoms include bruits over the upper abdomen or in the costovertebral angles, hematuria, and acute flank pain.
❑ Thyrotoxicosis. Accompanying the elevated systolic pressure associated with thyrotoxicosis, a potentially life-threatening disorder, are widened pulse pressure, tachycardia, bounding pulse, pulsations in the capillary nail beds, palpitations, weight loss, exophthalmos, an enlarged thyroid gland, weakness, diarrhea, a fever over 100° F (37.8° C), and warm, moist skin. The patient may appear nervous and emotionally unstable, displaying occasional outbursts or even psychotic behavior. Heat intolerance, exertional dyspnea and, in females, decreased or absent menses may also occur.
Other causes
❑ Drugs. Central nervous system stimulants (such as amphetamines), sympathomimetics, corticosteroids, nonsteroidal anti-inflammatory drugs, hormonal contraceptives, monoamine oxidase inhibitors, and over-the-counter cold remedies can increase blood pressure, as can cocaine abuse.HERB ALERT:Ginseng and licorice may cause high blood pressure or an irregular heartbeat. St. John's wort can also raise blood pressure, especially when taken with substances that antagonize hypericin, such as amphetamines, cold and hay fever medications, nasal decongestants, pickled foods, beer, coffee, wine, and chocolate.
❑ Treatments. Kidney dialysis and transplantation cause transient elevated blood pressure.
Special considerations
If routine screening detects elevated blood pressure, stress to the patient the need for follow-up diagnostic tests. Then prepare him for routine blood tests and urinalysis. Depending on the suspected cause of the increased blood pressure, radiographic studies, especially of the kidneys, may be necessary.If the patient has essential hypertension, explain the importance of long-term control of elevated blood pressure and the purpose, dosage, schedule, route, and adverse effects of prescribed antihypertensives. Reassure him that there are other drugs he can take if the one he's taking isn't effective or causes intolerable adverse reactions. Instruct him not to discontinue medications without contacting the physician. Encourage him to report adverse reactions; the drug dosage or schedule may simply need adjustment.
Be aware that the patient may experience elevated blood pressure only when in the physician's office (known as white-coat hypertension). In such cases, 24-hour blood pressure monitoring is indicated to confirm elevated readings in other settings. In addition, other risk factors for coronary artery disease, such as smoking and elevated cholesterol levels, need to be addressed.
Pediatric pointers
Normally, blood pressure in children is lower than it is in adults, an essential point to recognize when assessing a patient for elevated blood pressure. (See Normal pediatric blood pressure, page 87.)Elevated blood pressure in children may result from lead or mercury poisoning, essential hypertension, renovascular stenosis, chronic pyelonephritis, coarctation of the aorta, patent ductus arteriosus, glomerulonephritis, adrenogenital syndrome, or neuroblastoma. Treatment typically begins with drug therapy. Surgery may then follow in patients with patent ductus arteriosus, coarctation of the aorta, neuroblastoma, and some cases of renovascular stenosis. Diuretics and antibiotics are used to treat glomerulonephritis and chronic pyelonephritis; hormonal therapy, to treat adrenogenital syndrome.
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