Chapter 31: Disorders of Blood Flow and Blood Pressure Activity A, C & G (9th edition)

For people who suffer from hypertension and other diseases that affect blood pressure, important information about the status of their disease is gathered from measurements including systolic and diastolic pressures, pulse pressure, and mean arterial pressure. What is the mean arterial pressure estimated to be when the blood pressure is 130/85?

100. At normal heart rates, mean arterial pressure can be estimated by adding one third of the pulse pressure to the diastolic pressure (i.e. diastolic pressure + pulse pressure/3).

A diagnosis of hypertension is made if the systolic blood pressure is ____ or higher and the diastolic blood pressure is ____ or higher.

140 mm Hg, 90 mm Hg

The main objective for treatment of essential hypertension is to achieve and maintain arterial blood pressure below ____.

140/90 mm Hg

_______ drugs and _________ drugs are the most common cause of chronic orthostatic hypotension.

Antihypertension, Psychotropic

____ blood pressure reflects the rhythmic ejection of blood from the left ventricle into the aorta.

Arterial

Hypertension in the elderly is a common finding. This is because of the age-related rise in systolic blood pressure. Among the aging processes what is a contributor to hypertension?

Baroreceptor sensitivity. Among the aging process that contribute to an increase in blood pressure are a stiffening of the large arteries, particularly the aorta; decreased baroreceptor sensitivity; increased peripheral vascular resistance; and decreased renal blood flow.

The ____ blockers are effective in treating hypertension because they decrease heart rate and cardiac output, as they are cardioselective.

Beta-adrenergic

ACE inhibitors

Block formation of ANG II

The renin-angiotensin-aldosterone system plays a central role in blood pressure by increasing ___ and ____.

vessel constriction, fluid retention

____ lower blood pressure initially by decreasing vascular volume and cardiac output.

Diuretics

Pregnancy-induced hypertension is a serious condition affecting between 5% and 10% of pregnant women. The most serious classification of hypertension in pregnancy is preeclampsia-eclampsia. It is a pregnancy-specific syndrome that can have both maternal and fetal manifestations. What is a life-threatening manifestation of the preeclampsia-eclampsia classification of pregnancy-induced hypertension?

HELLP syndrome. Liver damage, when it occurs, may range from mild hepatocellular necrosis with elevation of liver enzymes to the more ominous hemolysis, elevated liver function tests, and low platelet count (HELLP) syndrome that is associated with significant maternal mortality.

A client with malignant hypertension is at risk for hypertensive crisis, including the cerebral vascular system often causing cerebral edema. As the nurse caring for this patient, what are the signs and symptoms you would assess for?

Headache and confusion. Cerebral vasoconstriction probably is an exaggerated homeostatic response designed to protect the brain from excesses of blood pressure and flow. The regulatory mechanisms often are insufficient to protect the capillaries, and cerebral edema frequently develops. As it advances, papilledema (i.e. swelling of the optic nerve at its point of entrance into the eye) ensues, giving evidence of the effects of pressure on the optic nerve and retinal vessels. The patient may have headache, restlessness, confusion, stupor, motor and sensory deficits, and visual disturbances. In severe cases, convulsions and coma follow. Lethargy, nervousness, and hyperreflexia are not signs or symptoms of cerebral edema in malignant hypertension.

The rennin-angiotensin-aldosterone system is a negative feedback system that plays a central role in blood pressure regulation. How does the end result of this feedback loop regulate blood pressure in the body?

Increases salt and water retention by the kidney. The renin-angiotensin-aldosterone system plays a central role in blood pressure regulation. Angiotensin II has two major functions in the renin-angiotensin-aldosterone system and acts as a both a short- and long- term regulation of blood pressure. It is a strong vasoconstrictor, especially of the arterioles regulating blood pressure in the short term. However, its second major action, the stimulation of aldosterone secretion from the adrenal gland, is the end of the renin-angiotensin-aldosterone loop. The aldosterone that is secreted notifies the kidneys to stop production of renin (the negative feedback in the loop) and contributes to the long term regulation of blood pressure by increasing salt and water retention in the kidney.

_________ hypertension is characterized by sudden marked elevations in blood pressure, with diastolic value above 120 mm Hg complicated by evidence of acute or rapidly progressive life-threatening organ dysfunction.

Malignant

The extended, severe exposure of the walls of the blood vessels to the exaggerated pressures that occur in malignant hypertension cause injuries to the walls of the arterioles. Blood vessels in the renal system are particularly vulnerable to this type of damage. Because hypertension is a chronic disease and is associated with autoregulatory changes in the blood flow to major organs, what would be the initial treatment goal for malignant hypertension?

Partial reduction in blood pressure to less critical values. Because chronic hypertension is associated with autoregulatory changes in coronary artery, cerebral artery, and kidney blood flow, care should be taken to avoid excessively rapid decreases in blood pressure, which can lead to hypoperfusion and ischemic injury. Therefore, the goal of initial treatment measures should be to obtain a partial reduction in blood pressure to a safer, less critical level, rather than to normotensive levels.

A 37-year-old woman is admitted to your unit with a differential diagnosis of rule out phenochromocytoma. What are the most common symptoms you would expect this patient to exhibit?

Periodic severe headache and marked variability in blood pressure. Like adrenal medullary cells, the tumor cells of phenochromocytoma produce and secrete the catecholamines epinephrine and norepinephrine. The hypertension that develops is a result of the massive release of these catecholamines. Their release may be paroxysmal rather than continuous, causing periodic episodes of headache, excessive sweating, and palpitations. Headache is the most common symptom and can be quite severe. Nervousness, tremor, facial pallor, weakness, fatigue, and weight loss occur less frequently. Marked variability in blood pressure between episodes is typical.

Nondippers

Persons with flat blood pressure profile

____ is defined as an elevation in blood pressure and proteinuria developing after 20 weeks of gestation.

Preeclampsia-eclampsia

____ hypertension is the term applied to 95% of cases in which no cause for hypertension can be identified. In ____ hypertension, the elevation of blood pressure results from some other disorder.

Primary, secondary

A 75-year-old man presents at the clinic for a routine physical check-up. He is found to be hypertensive. While taking his blood pressure in the sitting, standing, lying positions, the nurse notes that the brachial artery is pulseless at a high cuff pressure, but she can still feel it. What condition would the nurse suspect?

Pseudohypertension should be suspected in older persons with hypertension in whom the radial or brachial artery remains palpable but pulseless at higher cuff pressures. The presenting parameters of the patient are not compatible with essential, orthostatic, or secondary hypertension.

Although the etiology of essential hypertension is mainly unknown, several risk factors have been identified. These risk factors fall under the categories of constitutional risk factors and lifestyle factors. What are the primary risk factors for essential hypertension?

Race and excessive sodium chloride intake, type 2 diabetes and obesity, and family history and excessive alcohol consumption. The constitutional risk factors include a family history of hypertension, race, and age-related increases in blood pressure. Another factor that is thought to contribute to hypertension is insulin resistance and the resultant hyperinsulinemia that occurs in metabolic abnormalities such as type 2 diabetes. Lifestyle factors can contribute to the development of hypertension by interacting with other risk factors. These lifestyle factors include high salt intake, excessive calorie intake and obesity, excessive alcohol consumption, and low intake of potassium. Although stress can raise blood pressure acutely, there is less evidence linking it to chronic elevation in blood pressure. Smoking and a diet high in saturated fats and cholesterol, although not identified as primary risk factors for hypertension, are independent risk factors for coronary heart disease and should be avoided.

In infants and children, secondary hypertension is the most common form of hypertension. What is the most common cause of hypertension in an infant?

Renal artery thrombosis. Hypertension in infants is associated most commonly with high umbilical catheterization and renal artery obstruction of the aorta, and phenochromocytoma all can raise blood pressure; they are not the most common cause of hypertension in an infant.

The mean arterial blood pressure is determined mainly by the ____ and the ____.

cardiac output, peripheral vascular resistance

The ____ drugs inhibit the movement of calcium into cardiac and vascular smooth muscle.

calcium channel receptor-blocking

The ____ risk factors include a family history of hypertension, race, and age-related increases in blood pressure.

constitutional

Diastolic hypertension

diastolic pressure over 90 mm Hg

The extracellular fluid volume and arterial blood pressure are regulated around an ____ point, which represents the normal pressure for a given individual.

equilibrium

ANG II

strong vasoconstrictor, reduces sodium excretion

Vasopressin

increases renal water retention

Hypertension is a major risk factor for ___ stroke and intracerebral ____.

ischemic, hemorrhage

The role that the ____ play in blood pressure regulation is emphasized by the fact that many hypertension medications produce their blood pressure-lowering effects by increasing ____ and ____ elimination.

kidneys, sodium, water

An elevation in blood pressure increases the workload of the ____ by increasing the pressure against which the heart must pump as it ejects blood into the systemic circulation.

left ventricle

The ____ represents the average pressure in the arterial system during ventricular contraction and relaxation.

mean arterial pressure

Coarctation of the aorta

narrowing of the aorta

Chronic hypertension leads to _____, a common cause of chronic kidney disease.

nephrosclerosis

The use of ____ pills is probably the most common cause of secondary hypertension in young women.

oral contraceptive

Any disease condition that reduces blood volume, impairs mobility, results in prolonged inactivity, or impairs autonomic nervous system function may also predispose to ____.

orthostatic hypotension

Dippers

persons whose blood pressure follows circadian rhythms

The difference between the systolic and diastolic pressure (approximately 40 mmHg) is called the ____.

pulse pressure

Many of the conditions causing _____ hypertension can be corrected or cured by surgery or specific medical treatment.

secondary

Elevated pressures during ____ favor the development of left ventricular hypertrophy, increased myocardial oxygen demands, and eventual left heart failure.

systole

Systolic hypertension

systolic pressure over 140 mm Hg

The pressure at the height of the pressure pulse is ____ pressure, and the lowest pressure is the ____ pressure.

systolic, diastolic