PrepU Week 10

The nurse and nursing student are caring for a client with a condition causing deficiency of ADH. The nurse recognizes that the student understands the origin of this process when the student states ADH is produced in which of these areas? a) Pituitary gland b) Adrenal gland c) Renal cortex d) Osmoreceptors

A (ADH assists in maintenance of the extracellular fluid volume by controlling the permeability of the medullary collecting tubules. Osmoreceptors in the hypothalamus sense an increase in osmolality of extracellular fluids and stimulate the release of ADH from the posterior pituitary gland. In exerting its effect, ADH, also known as vasopressin, binds to receptors on the basolateral side of the tubular cells.)

A client has been prescribed a drug that is not removed quickly by renal filtration. The drug likely has this quality because it is: a) bound to plasma proteins. b) a hydrophilic weak base. c) a hydrophilic weak acid. d) water soluble.

A (If the drug is bound to plasma proteins, it will not enter the filtrate. Hydrophilic acids and bases are easily eliminated by renal filtration. A water soluble drug is not immune to renal filtration.)

A patient is scheduled for a creatinine clearance test to measure the glomerular filtration rate (GFR). The patient asks the nurse what this test is used for. Which of the following is the nurse's best response? a) "This test provides a gauge of renal function." b) "This test measures circulating antidiuretic hormone levels." c) "This test measures urine-specific gravity." d) "This test measures the volume of urine output."

A (The GFR is the amount of filtrate that is formed each minute as blood moves through the glomeruli. The clearance rate for creatinine is the amount that is completely cleared by the kidneys in 1 minute.)

In addition to regulating body fluids and electrolytes, the kidneys function in maintaining bone calcium levels by doing which of the following? a) Activating vitamin D b) Excreting bicarbonate c) Synthesizing erythropoietin d) Stimulating bone marrow

A (The kidneys aid in calcium metabolism by activating vitamin D after it is chemically converted by the liver. Bicarbonate buffering is unrelated to activation of vitamin D. Bone marrow is stimulated by the synthesis of erythropoietin to form red blood cells, which is unrelated to calcium levels.)

A nurse educator is explaining the importance of maintaining GFR for the maintenance of homeostasis. Which play an essential role in maintaining a constant GFR? a) Macula densa b) Renin c) Nitric oxide d) Prostaglandin

A (The macula densa monitors filtrate flow in the distal tubule and communicates with juxtaglomerular cells of the afferent arteriole. Together they form the juxtaglomerular apparatus and regulate GFR. Prostaglandins, nitric oxide, and renin do not directly influence GFR.)

Which of the following can be eliminated from the body by the kidneys as a means of regulating body acid-base balance when urine buffers are present? a) Hydrogen (H+) b) Potassium (K+) c) Phosphate (HPO4) d) Ammonia (NH3)

A

In the emergency department, a client arrives following a car accident. His pulse is 122; BP 88/60; respiration is 18 bpm. Urine output is 4 mL over the first hour on arrival. When in shock, this lower urine output is primarily due to: a) high filtration rates in the glomerulus. b) innervation of the sympathetic nervous system causing constriction of the afferent arteriole. c) obstruction in the glomerular capillaries due to overabundance of large molecules being released. d) parasympathetic stimulation causing the renal arteries to constrict in response to pain.

B (During periods of strong sympathetic stimulation, such as shock, constriction of the afferent arteriole causes a marked decrease in renal blood flow, and thus glomerular filtration pressure. Consequently, urine output can fall almost to zero. The location of the glomerulus between two arterioles allows for maintenance of a high-pressure filtration system. The glomerular filtrate has a chemical composition similar to plasma, but contains almost no proteins because large molecules do not readily pass through the openings in the glomerular capillary wall.)

Select the percentage of cardiac output that perfuses the kidneys. a) 15% to 20% b) 20% to 25% c) 10% to 15% d) 25% to 30%

B (In the adult, the kidneys are perfused with 1000 to 1300 mL of blood per minute, or 20% to 25% of the cardiac output; 10% to 15% and 15% to 20% represent a lower percentage; 25% to 30% is an increased percentage.)

A nursing student studying pharmacology is learning how angiotensin converting enzyme inhibitors (ACE) work. The student is correct when the student states the mechanism of action of ACE inhibitors is which of these? a) Prevent reabsorption of sodium in the distal tubules b) Prevent conversion of angiotensin I to II c) Promote osmotic diuresis d) Block aldosterone

B (The juxtaglomerular cells of the kidney contain granules of inactive renin, an enzyme that functions in the conversion of angiotensinogen to angiotensin. Angiotensin I is converted to angiotensin II in the presence of converting enzyme. By blocking converting enzyme, angiotensin II, a potent vasoconstrictor, is not produced, lowering blood pressure.)

A client asks the nurse what may have caused elevation in urinary protein levels (proteinuria) on a urine test. The best response by the nurse would be: a) Decrease in antidiuretic hormone b) Abnormal glomeruli filtration c) Urinary tract infection d) Poor fluid intake

B (Urine tests for proteinuria are used to detect abnormal filtering of albumin by the glomeruli or defects in its reabsorption in the renal tubules.)

In the intensive care unit (ICU), the nurse is caring for a trauma client who has abdominal injuries is beginning to have a decrease in BP and increased pulse rate and is pale with diaphoretic skin. The nurse is assessing the client for hemorrhagic shock. If the client is in shock, the nurse would expect to find: a) Complaints of flank pain rotating around the abdominal muscles b) An increase in GFR due to relaxation of the afferent arterioles c) Significant decrease in urine output due to decrease in renal blood flow d) Excess output of blood-tinged urine

C (During periods of strong sympathetic stimulation, such as shock, constriction of the afferent arteriole causes a marked decrease in renal blood flow and thus glomerular filtration pressure. Consequently, urine output can fall almost to 0. Unless the injury is specific to the kidney, the client will not have blood in urine and urine production will not be excessive. Flank pain is associated with obstruction due to stone formation. The GFR will decrease rather than increase.)

A new client on hemodialysis is watching his blood being filtered through a dialyzer. He asks the nurse how much blood typically passes through the kidney every minute? The nurse responds: a) 1700-2000 mL/minute. b) 100-300 mL/minute. c) 1000-1300 mL/minute. d) 500-800 mL/minute.

C (In the adult, the kidneys are perfused with 1000 to 1300 mL of blood per minute, or 20% to 25% of the cardiac output.)

Clients with CKD are at risk for demineralization of their bones since they are no longer able to: a) Excrete bicarbonate effectively b) Stimulate bone osteoclastic production c) Transform vitamin D to its active form d) Synthesize erythropoietin

C (The kidneys aid in calcium metabolism by activating vitamin D, after it is chemically converted by the liver. Bicarbonate buffering is unrelated to activation of vitamin D. Bone marrow is stimulated by the synthesis of erythropoietin to form red blood cells, which is unrelated to calcium levels.)

Select the option that identifies the function of the kidneys in maintaining normal composition of internal body fluids. a) Production of erythropoietin for red blood cell production b) Conversion of vitamin D to active form c) Filtration and reabsorption of physiologically essential substances d) Excretion of the renin-angiotensin mechanism

C (The kidneys filter physiologically essential substances, such as sodium and potassium, from the blood, and selectively reabsorb those substances that are needed to maintain the normal composition of internal body fluids. Substances that are not needed or are in excess of those needed pass into the urine. In addition to regulating the volume and composition of body fluids, the kidneys also perform endocrine functions. They release renin, an enzymatic hormone that participates in the regulation of blood pressure and maintenance of the circulating blood volume; they produce erythropoietin, a hormone that stimulates red blood cell production; and they convert vitamin D to its active form.)

The nurse is caring for a client with an elevated blood urea nitrogen (BUN) level. Which of these factors is least likely to alter the blood urea nitrogen value? a) Protein intake b) Dehydration c) Thyroid disease d) Gastrointestinal bleeding

C (Urea is formed in the liver as a by-product of protein metabolism and is eliminated entirely by the kidneys. BUN is related to the GFR but, unlike creatinine, also is influenced by protein intake, gastrointestinal bleeding, and hydration status.)

The nurse is caring for a client who is diagnosed with gout. Which of these laboratory studies does the nurse monitor to monitor this condition? a) Bicarbonate levels b) Potassium levels c) Uric acid levels d) Urea nitrogen levels

C (Uric acid is a product of purine metabolism. Excessively high blood levels (i.e., hyperuricemia) can cause gout, and excessive urine levels can cause kidney stones.)

Urine specific gravity is normally 1.010 to 1.025 with adequate hydration. When there is loss of renal concentrating ability due to impaired renal function, low concentration levels are exhibited. When would the nurse consider the low levels of concentration to be significant? a) After a nap b) Last void at night c) First void in morning d) At noon

C (With diminished renal function, there is a loss of renal concentrating ability, and the urine specific gravity may fall to levels of 1.006 to 1.010 (usual range is 1.010 to 1.025 with normal fluid intake). These low levels are particularly significant if they occur during periods that follow a decrease in water intake.)

Although an average of ____ glomerular filtrate is formed each minute, only _____ is excreted as urine and the rest is reabsorbed in the tubules. a) 250 mL; 15 mL b) 175 mL; 10 mL c) 125 mL; 1 mL d) 200 mL; 5 mL

C (Although an average of 125 mL of filtrate is formed each minute, only 1 mL is excreted in urine and the other 124 mL is reabsorbed across the tubular membrane.)

Which substance, released by the atria, causes vasodilation of the afferent and efferent arterioles, which results in an increase in renal blood flow and glomerular filtration rate (GFR)? a) Angiotensin I b) Aldosterone c) Atrial natriuretic peptide (ANP) d) Antidiuretic hormone (ADH)

C (Atrial natriuretic peptide is a hormone that is synthesized in the muscle cells of the atria of the heart and released when the atria are stretched. The actions of ANP include vasodilation of the afferent and efferent arterioles, which results in an increase in renal blood flow and glomerular filtration rate. Angiotensin I, which has few vasoconstrictor properties, leaves the kidneys and enters the circulation. ADH and aldosterone would decrease blood flow and GFR.)

A nurse is evaluating a patient's morning laboratory values. Which of the following results requires that the nurse notify the health care provider? a) Sodium: 148 mEq/L b) Blood urea nitrogen: 20.0 mg/dL c) Potassium: 3.4 mEq/L d) Creatinine: 10.6 mg/dL

D (A rise in the serum creatinine level to three times its normal value suggests that there is a 75% loss of renal function, and with creatinine values of 10 mg/dL or more, it can be assumed that approximately 90% of renal function has been lost.)

To treat enuresis in a young girl, her pediatrician prescribes desmopressin, an antidiuretic hormone (ADH) nasal spray, before bedtime. Which rationale for this treatment is the most likely? a) It causes tubular cells to lose their water permeability. b) It leads to the production of dilute urine. c) It lessens the amount of fluid entering the glomerulus. d) It removes water from the filtrate and returns it to the vascular compartment.

D (ADH maintains extracellular volume by returning water to the vascular compartment. This leads to the production of concentrated urine by removing water from the tubular filtrate. In exerting its effect, ADH produces a marked increase in water permeability in tubular cells.)

When caring for the client with proteinuria, the nurse recognizes dysfunction in which of these structures of the kidney allows protein to leak into the urine? a) Calyx b) Collecting tubule c) Renal pelvis d) Glomerulus

D (Alterations in the structure and function of the glomerular basement membrane are responsible for the leakage of proteins and blood cells into the filtrate that occurs in many forms of glomerular disease.)

The nurse teaches the client with end-stage kidney disease who has developed anemia that the reason anemia has developed is which of these? a) Activation of vitamin D cannot occur when kidneys are damaged. b) Medications taken for kidney disease destroy the red blood cells. c) Clients with kidney disease must avoid consuming iron. d) The damaged kidney is unable to produce erythropoietin.

D (Persons with end-stage kidney disease often are anemic because of an inability of the kidneys to produce erythropoietin, the hormone that regulates the differentiation of red blood cells in the bone marrow.)

It is known that high levels of uric acid in the blood can cause gout, while high levels in the urine can cause kidney stones. What medication competes with uric acid for secretion in to the tubular fluid, thereby reducing uric acid secretion? a) Acetaminophen b) Advil c) Ibuprofen d) Aspirin

D (Small doses of aspirin compete with uric acid for secretion into the tubular fluid and reduce uric acid secretion, and large doses compete with uric acid for reabsorption and increase uric acid excretion in the urine.)

The kidney assists in blood pressure regulation by releasing which of the following from the juxtaglomerular cells in response to decreased renal blood flow, resulting in efferent arteriole vasoconstriction? a) Angiotensin I b) Aldosterone c) Angiotensin II d) Renin

D (The kidney releases renin, which enters the bloodstream to convert angiotensinogen to angiotensin I. )

The nurse is caring for a client who has produced an average of 20 ml/hour for the previous day. The nurse recognizes this compares in which way to the normal urine output? a) This represents normal urinary output for 24 hours. b) The kidneys should produce a minimum of 10 ml/hour over one day. c) The normal kidney produces an average 3000 ml of urine daily. d) The kidneys should produce about 1.5 liters of urine each day.

D (The kidneys normally produce approximately 1.5 L or 1500 ml of urine each day.)

The nurse should anticipate that a client who collapsed while running his or her first marathon and has a urine specific gravity of 1.035 is experiencing: a) Frostbite b) Sun stroke c) Exhaustion d) Dehydration

D (The usual range of specific gravity is 1.010 to 1.025 with normal fluid intake. Healthy kidneys can produce concentrated urine with specific gravity of 1.030 to 1.040 during periods of dehydration and dilute urine with a specific gravity that approaches 1.000 during periods of too much fluid intake.)

The nurse is reviewing the results of a renal client's laboratory results. This client's urine specific gravity allows the nurse to assess the kidneys' ability to: a) excrete excess hydrogen ions. b) excrete potassium. c) concentrate protein. d) concentrate urine.

D (Urine specific gravity is used to assess the kidneys' ability to concentrate urine and provides a valuable index of the hydration status and functional ability of the kidneys. Specific gravity does not evaluate electrolyte or acid--base functions of the kidneys. It is not affected by protein levels.)