Med Surg - Ch 45

Question 1

Which important functions of regulation of water balance and acid-base balance occur in the distal convoluted tubes of the nephron (select all that apply)?

a. Secretion of H+ into filtrate
b. Reabsorption of water without ADH
c. Reabsorption of Na+ in exchange for K+
d. Reabsorption of glucose and amino acids
e. Reabsorption of water under ADH influence
f. Reabsorption of Ca+2 under parathormone influence

Answer 1

a, c, e, f (Secretion of H+ into filtrate, reabsorption of Na+ in exchange for K+, reabsorption of water under ADH influence, reabsorption of Ca+2 under parathormone influence)

The distal tubules regulate water and acid-base balance by reabsorption of water under antidiuretic hormone (ADH) influence, secreting H+ and reabsorbing bicarbonate, reabsorption of Na+ in exchange for K+, and reabsorption of Ca+2 with the influence of parathormone. The reabsorption of water without ADH occurs in the proximal convoluted tubule and the descending loop of Henle. The reabsorption of glucose and amino acids occurs in the proximal convoluted tubule. Active reabsorption of Cl- and passive reabsorption of Na+ occurs in the ascending loop of Henle.

Question 2

Number the following physiologic occurrences in the order they occur in the formation of urine. Begin with 1 for the first occurrence and number through 6 for the last occurrence in the formation of urine.

Answer 2

1: a. Blood is filtered in the glomerulus.
2: f. Ultrafiltrate flows from Bowman’s capsule and passes down the tubules without blood cells, platelets, or large plasma proteins.
3: c. Reabsorption of electrolytes, glucose, amino acids, and small proteins in the tubules.
4: b. Reabsorption of water in the loop of Henle.
5: e. Active reabsorption of chloride (Cl-) ions and passive reabsorption of sodium (Na+) ions in the ascending loop of Henle.
6: d. Acid-base regulation with conservation of bicarbonate (HCO3-) and secretion of excess H+ in the distal tubule.

Blood is filtered in the glomerulus and the ultrafiltrate flows from the Bowman’s capsule to the tubules for reabsorption of essential materials and secretion of nonessential ones. In the proximal convoluted tubule, most electrolytes, glucose, amino acids, and small proteins are reabsorbed. Water is conserved in the loop of Henle with chloride and sodium reabsorbed in the ascending loop. The distal convoluted tubules complete final water balance and acid-base balance.

Question 3

The right atrium myocytes secrete atrial natriuretic peptide (ANP) when there is increased plasma volume. What actions does ANP take to produce a large volume of dilute urine (select all that apply)?

a. Inhibits renin
b. Increases ADH
c. Inhibits angiotensin II action
d. Decreases sodium excretion
e. Inhibits angiotension II action

Answer 3

a, c (inhibits renin, inhibits angiotensin II action)

Atrial natural peptide (ANP) responds to increased atrial distention by increasing sodium excretion and inhibiting renin, ADH, and angiotensin action. Aldosterone secretion is also suppressed. ANP also causes afferent arteriole relaxation that increases the glomerular filtration rate (GFR).

Question 4

Which statement accurately describes the glomerular filtration rate (GFR)?

a. The primary function of GFR is to excrete nitrogenous waste products.
b. Decreased permeability in the glomerulus causes loss of proteins into the urine.
c. The GFR is primarily dependent on adequate blood flow and adequate hydrostatic pressure.
d. The GFR is decreased when prostaglandins cause vasodilation and increased renal blood flow.

Answer 4

c. The GFR is primarily dependent on adequate blood flow and adequate hydrostatic pressure

GFR is primarily dependent on adequate blood flow and hydrostatic pressure. The glomerulus filters the blood. The GFR is the amount of blood filtered each minute by the glomeruli, which determines concentration of urea in the blood. Increased permeability in the glomerulus causes loss of proteins in the urine. The prostaglandins increase the GFR with increased renal blood flow.

Question 5

A patient with obstruction of the renal artery causing renal ischemia exhibits hypertension. What is one factor that may contribute to the hypertension?

a. Increased renin release
b. Increased ADH secretion
c. Decreased aldosterone secretion
d. Increased synthesis and release of prostaglandins

Answer 5

a. Increased renin release

Renin is released in response to decreased arterial blood pressure (BP), renal ischemia, decreased extracellular fluid (ECF), decreased serum Na+ concentration, and increased urinary Na+ concentration. It is the catalyst of the renin-angiotensin-aldosterone system, which raises BP when stimulated. ADH is secreted by the posterior pituitary in response to serum hyperosmolality and low blood volume. Aldosterone is secreted only after stimulation by angiotensin II. Kidney prostaglandins lower BP by causing vasodilation.

Question 6

In which clinical situation would the increased release of erythropoietin be expected?

a. Hypoxemia
b. Hypotension
c. Hyperkalemia
d. Fluid overload

Answer 6

a. Hypoxemia

Erythropoietin is released when the oxygen tension of the renal blood supply is low and stimulates production of red blood cells in the bone marrow. Hypotension causes activation of the renin-angiotensin-aldosterone system, as well as release of ADH. Hyperkalemia stimulates the release of aldosterone from the adrenal cortex and fluid overload does not directly stimulate factors affecting the erythropoietin release by the kidney.

Question 7

What are common diagnostic studies done for a patient with severe renal colic (select all that apply)?

a. CT scan
b. Urinalysis
c. Cystoscopy
d. Ureteroscopy
e. Abdominal ultrasound

Answer 7

a, b, e (CT scan, urinalysis, ureteroscopy)

Testing would include urinalysis to see crystals and look for red blood cells. Abdominal ultrasound and CT scan may also be done.

Question 8

Which volume of urine in the bladder would cause discomfort and require urinary catheterization?

a. 250 mL
b. 500 mL
c. 1200 mL
d. 1500 mL

Answer 8

b. 500 mL

When the amount of urine in the bladder has reached 1200 mL, the person would need relief and probably catheterization. The bladder capacity ranges from 600 to 1000 mL. When there is 250 mL of urine in the bladder, the person will usually feel the urge to urinate and 400 to 600 mL will be uncomfortable.

Question 9

What is a factor that contributes to an increased incidence of urinary tract infections in aging women?

a. Length of the urethra
b. Larger capacity of bladder
c. Relaxation of pelvic floor and bladder muscles
d. Tight muscular support at the urinary sphincter

Answer 9

c. Relaxation of pelvic floor and bladder muscles

Relaxation of female urethra, bladder, vagina, and pelvic floor muscles may contribute to stress and urge incontinence and urinary tract infections. The short urethra of women allows easier ascension and colonization of bacteria in the bladder than occurs in men and the urethra does not lengthen with age. The bladder capacity of men and women is the same but decreases with aging.

Question 10

A 78-year-old man asks the nurse why he has to urinate so much at night. The nurse should explain to the patient that as an older adult, what may contribute to his nocturia?

a. Decreased renal mass
b. Decreased detrusor muscle tone
c. Decreased ability to conserve sodium
d. Decreased ability to concentrate urine

Answer 10

d. Decreased ability to concentrate urine

Decreased renal blood flow and altered hormone levels result in a decreased ability to concentrate urine that results in an increased volume of dilute urine, which does not maintain the usual diurnal elimination pattern. A decrease in bladder capacity also contributes to nocturia but decreased bladder muscle tone results in urinary retention. Decreased renal mass decreases renal reserve but function is generally adequate under normal circumstances.

Question 11

What accurately describes a normal physical assessment of the urinary system by the nurse?

a. Auscultates the lower abdominal quadrants for fluid sounds
b. Palpates an empty bladder at the level of the symphysis pubis
c. Percusses the kidney with a firm blow at the posterior costovertebral angle
d. Positions the patient prone to palpate the kidneys with a posterior approach

Answer 11

c. Percusses the kidney with a firm blow at the posterior costovertebral angle

To assess for kidney tenderness, the nurse strikes the fist of one hand over the dorsum of the other hand at the posterior costovertebral angle. The upper abdominal quadrants and costovertebral angles are auscultated for vascular bruits in the renal vessels and aorta and an empty bladder is not palpable. The kidneys are palpated through the abdomen, with the patient supine.

Question 12

The physician documented that the patient has urinary retention. How should the nurse explain this when the nursing student asks what it is?

a. Inability to void
b. No urine formation
c. Large amount of urine output
d. Increased incidence of urination

Answer 12

a. Inability to void

Retention is the inability to void. Anuria is no urine formation. Polyuria is a large amount of urine output over time. Frequency is increased incidence of urination.

Question 13

The mother of an 8-year-old girl has brought her child to the clinic because she is wetting the bed at night. What terminology should the nurse use when documenting this situation?

a. Ascites
b. Dysuria
c. Enuresis
d. Urgency

Answer 13

e. Enuresis

Enuresis is involuntary urination at night. Ascites is excess fluid in the intraperitoneal cavity. Dysuria is painful urination. Urgency is the feeling of needing to void immediately.

Question 14

A urinalysis of a urine specimen that is not processed within 1 hour may result in an erroneous measurement of

a. glucose.
b. bacteria.
c. specific gravity.
d. white blood cells.

Answer 14

b. bacteria

Bacteria in warm urine specimens multiply rapidly and false or unreliable bacterial counts may occur with urine that has been sitting for periods of time.

Question 15

Which urinalysis results most likely indicate a urinary tract infection (UTI)?

a. Yellow; protein 6 mg/dL; ph 6.8; 10^2/mL bacteria
b. Cloudy, yellow; WBC >5/hpf; pH 8.2; numerous casts
c. Cloudy, brown; ammonia odor; specific gravity 1.030; RBC 3/hpf
d. Clear; colorless; glucose: trace; ketones: trace; osmolality 500 mOsm/kg (500 mmol/kg)

Answer 15

b. Cloudy, yellow; WBC >5/hpf; pH 8.2; numerous casts

Cloudiness in a fresh urine specimen, WBC count above 5 per high-power field (hpf), and the presence of casts are all indicative of urinary tract infection (UTI). The pH is usually elevated because bacteria in urine split the urea alkaline ammonia. Cloudy, brown urine usually indicates hematuria or the presence of bile. Colorless urine is usually very dilute. Option a is characteristic of normal urine.

Question 16

Which urine specific gravity value would indicate to the nurse that the patient is receiving excessive IV fluid therapy?

a. 1.002
b. 1.010
c. 1.025
d. 1.030

Answer 16

a. 1.002

A urine specific gravity of 1.002 is low, indicating dilute urine and the excretion of excess fluid. Fluid overload, diuretics, or lack of ADH can cause dilute urine. Normal urine specific gravity is 1.003 to 1.030. A high urine specific gravity indicates concentrated urine that would be seen in dehydration.

Question 17

After a patient had a renal arteriogram and is back on the clinical unit, what is the most important action by the nurse?

a. Observe for gross bleeding in the urine.
b. Place the patient in high Fowler’s position.
c. Monitor the patient for signs of allergy to the contrast medium.
d. Assess peripheral pulses in the involved leg every 30 to 60 minutes.

Answer 17

d. Assess peripheral pulses in the involve leg every 30 to 60 minutes.

During a renal arteriogram, a catheter is inserted, most commonly at the femoral artery. Following the procedure the patient is positioned with the affected leg extended with a pressure dressing applied. Peripheral pulse monitoring is essential to detect the development of thrombi around the insertion site, which may occlude blood supply to the leg. Gross bleeding in the urine is a complication of a renal biopsy. Allergy to the contrast medium should be established before the procedure.

Question 18

Which test is most specific for renal function?

a. Renal scan
b. Serum creatinine
c. Creatinine clearance
d. Blood urea nitrogen (BUN)

Answer 18

c. Creatinine clearance

The rate at which creatinine is cleared from the blood and eliminated in the urine approximates the GFR and is the most specific test of renal function. The renal scan is useful in showing the location, size, and shape of the kidney and general blood perfusion.

Question 19

What is the most likely reason that the BUN would be increased in a patient?

a. Has impaired renal function
b. Has not eaten enough protein
c. Has decreased urea in the urine
d. May have nonrenal tissue destruction

Answer 19

a. Has impaired renal function

The blood urea nitrogen (BUN) is increased in patients with renal problems. It may also be increased when there is rapid or extensive tissue damage from other causes. Low protein intake may cause a low BUN.

Question 20

What impairment in kidney function would cause the following laboratory findings in a patient with kidney disease?
Serum Ca2+: 7.2 mg/dL (1.8 mmol/L)
Hgb: 9.6 g/dL (96 g/L)
Serum creatinine: 3.2 mg/dL (283 mmol/L)

Answer 20

Serum Ca2+: 7.2 mg/dL (1.8 mmol/L)
Impaired conversion of inactive vitamin D to active vitamin D results in poor calcium absorption from the bowel, resulting in hypocalcemia.

Hgb: 9.6 g/dL (96 g/L)
Loss of cells that produce erythropoietin results in lack of stimulation of bone marrow to produce RBCs.

Serum creatinine: 3.2 mg/dL (283 mmol/L)
This serum creatinine level is high, indicating the loss of tubular secretion (passage of substances from the blood into the tubule) by the kidney.

Question 21

Priority decision: Following a renal biopsy, what is the nurse’s priority?

a. Offer warm sitz baths to relieve discomfort.
b. Test urine for microscopic bleeding with a dipstick.
c. Expect the patient to experience burning on urination.
d. Monitor the patient for symptoms of a urinary infection.

Answer 21

b. Test urine for microscopic bleeding with a dipstick

Bleeding from the kidney following a biopsy is the most serious complication of the procedure and urine must be examined for both gross and microscopic blood, in addition to vital signs and hematocrit levels being monitored. Following a cytoscopy the patient may have burning with urination and warm sitz baths may be used. Urinary infections are a complication of any procedure requiring instrumentation of the bladder.

Question 22

What nursing responsibilities are done to obtain a clean-catch urine specimen from a patient (select all that apply)?

a. Use sterile container.
b. Must start the test with full bladder.
c. Insert catheter immediately after voiding.
d. Have the patient void, stop, and void in container.
e. Have the patient clean the meatus before voiding.

Answer 22

a, d, e (use sterile container; have the patient void, stop, and void in container; have the patient clean the meatus before voiding)

A clean-catch urine specimen is obtained in a sterile container after cleaning the meatus. The patient will void a small amount in the toilet, stop, and then void in the container to catch the urine midstream. The first morning specimen is best for urinalysis. A full bladder is necessary for a urine flow study. A urinary catheter is inserted immediately after voiding to assess residual urine.

Question 23

Which diagnostic study would include assessing for iodine sensitivity, teaching the patient to take a cathartic the night before the procedure, and telling the patient that a salty taste may occur during the procedure?

a. Cystometrogram
b. Renal arteriogram
c. Intravenous pyelogram (IVP)
d. Kidneys, ureters, bladder (KUB)

Answer 23

c. Intravenous pyelogram (IVP)

A cathartic the evening before the procedure and sensitivity to iodine are important for both intravenous pyelogram (IVP) and renal arteriogram but the salty taste is only a possibility with IVP. The cystometrogram involves filling the bladder with water or saline to measure tone and stability. The kidneys, ureters, and bladder (KUB) is an x-ray that may have bowel preparation.

Question 24

A renal stone in the pelvis of the kidney will alter the function of the kidney by interfering with

a. the structural support of the kidney.
b. regulation of the concentration of urine.
c. the entry and exit of blood vessels at the kidney.
d. collection and drainage of urine from the kidney.

Answer 24

d. collection and drainage of urine from the kidney

The outer layer of the kidney is the cortex, and the inner layer is the medulla. The medulla consists of a number of pyramids. The apices (tops) of these pyramids are called papillae, through which urine passes to enter the calyces. The minor calyces widen and merge to form major calyces, which form a funnel-shaped sac called the renal pelvis. The minor and major calyces transport urine to the renal pelvis, from which it drains through the ureter to the bladder.

Question 25

A patient with kidney disease has oliguria and a creatinine clearance of 40 mL/min. These findings most directly reflect abnormal function of

a. tubular secretion.
b. glomerular filtration.
c. capillary permeability.
d. concentration of filtrate.

Answer 25

b. glomerular filtration

The amount of blood filtered each minute by the glomeruli is expressed as the glomerular filtration rate (GFR). The normal GFR is about 125 mL/min.

Question 26

Diminished ability to concentrate urine, associated with aging of the urinary system, is attributed to

a. a decrease in bladder sensory receptors.
b. a decrease in the number of functioning nephrons.
c. decreased function of the loop of Henle and tubules.
d. thickening of the basement membrane of Bowman’s capsule.

Answer 26

c. decreased function in the loop of Henle and tubules

Older adults have decreased function of the loop of Henle and tubules, which results in the loss of normal diurnal excretory pattern because of a decreased ability to concentrate urine and because of less concentrated urine.

Question 27

A diagnostic study that indicates renal blood flow, glomerular filtration, tubular function, and excretion is a(n)

a. IVP.
b. VCUG.
c. renal scan.
d. loopogram.

Answer 27

c. renal scan

A renal scan is used to evaluate the anatomic structures, perfusion, and function of kidneys. The scan shows the location, size, and shape of the kidneys and helps assess blood flow, glomerular filtration, tubular function, and urinary excretion.

Question 28

During physical assessment of the urinary system, the nurse

a. palpates an empty bladder as a small nodule.
b. auscultates over each CVA to detect impaired renal blood flow.
c. finds a dull percussion sound when 100 mL of urine is present in the bladder.
d. palpates above the symphysis pubis to determine the level of urine in the bladder.

Answer 28

b. auscultates over each CVA to detect impaired renal blood flow

The bell of the stethoscope may be used to auscultate over the costovertebral angle (CVA) and the upper abdominal quadrants. With this technique, the abdominal aorta and renal arteries are auscultated for a bruit (i.e., abnormal murmur), which indicates impaired blood flow to the kidneys..