Patho Ch 32
b) Spills into the urine Pg. 848 Proximal Tubule When the substance (such as blood glucose) exceeds the number of carrier proteins available for transport, the transport maximum has been exceeded, the renal threshold is reached, and the substance will spill (not reabsorb) into the urine. Sodium cotransport helps to move the substance back into the tubule.
1. When the glomerular transport maximum for blood glucose is exceeded and its renal threshold has been reached, what happens to the excess glucose? a) Sodium countertransport b) Spills into the urine c) Attaches to protein carriers d) Reabsorbs quickly
b) Macula densa Pg. 852 The Juxtaglomerular Complex 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.
10. A nurse educator is explaining the importance of maintaining GFR for the maintenance of homeostasis. Which of these plays an essential role in maintaining a constant GFR? a) Prostaglandins b) Macula densa c) Renin d) Nitric oxide
c) Excessive urine output Pg. 848 The Loop of Henle ADH regulates the ability of the kidneys to concentrate urine. When ADH is present, the water that moved from the blood into the urine filtrate in the glomeruli is returned to the circulatory system, and when ADH is absent, the water is excreted in the urine. Pathologically, deficiency of ADH leads to polyuria and dehydration.
11. The nurse is caring for a client with a condition of deficiency of antidiuretic hormone (ADH). When assessing the client, which finding does the nurse anticipate? a) Low blood pressure b) Retention of chloride c) Excessive urine output d) Retention of sodium
a) Elevated urine specific gravity Pg. 856 Urine Tests Gravity of 1.030 to 1.040. During periods of marked hydration, the specific gravity can approach 1.000. 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).
12. The nurse is caring for a client with suspected dehydration. Which results does the nurse recognize will help confirm this diagnosis? a) Elevated urine specific gravity b) Casts in the urine c) White blood cells in the urine d) Blood in the urine
b) A flexible, lighted tube will be inserted into the bladder and a tissue sample will be taken Pg. 858 Cytoscopy and Ureteroscopy Cystoscopy allows direct visualization of the urethra, bladder, and ureteral orifices. A cystoscope, an instrument with a lighted lens, is inserted through the urethra into the bladder. Biopsy specimens, lesions, small stones, and foreign bodies can be removed from the bladder.
13. The nurse is preparing the client with suspected bladder cancer for a biopsy via cystoscopy. What does the nurse teach the client about cystoscopy? a) Shock waves will be applied to the suprapubic area and catheterization will remove the debris for tissue analysis b) A flexible, lighted tube will be inserted into the bladder and a tissue sample will be taken c) A catheter will be inserted through the femoral artery, dye injected and a sample of the tissue taken d) A small flank incision will be performed and a tissue specimen taken
d) "The doctor will insert a lighted tube through my urethra into my bladder in order to inspect the inside of the bladder" Pg. 858 Cytoscopy and Ureteroscopy Cystoscopy provides a means for direct visualization of the urethra, bladder, and ureteral orifices. It relies on the use of a cystoscope, an instrument with a lighted lens. The cystoscope is inserted through the urethra into the bladder. Biopsy specimens, lesions, small stones, and foreign bodies can be removed from the bladder.
14. A nurse is teaching a client scheduled for a cystoscopy about the procedure. Which statement made by the client verifies that the teaching has been successful? a) "The doctor will insert a lighted tube into the bladder, and little catheters will be inserted through the tube into my kidney" b) "The doctor will inject a radioactive solution into my vein. The dye will distribute through my body and can be monitored by x-ray as it travels through my kidneys to my bladder" c) "The doctor will place a catheter into an artery in my groin and inject a dye that will visualize the blood supply to the kidneys" d) "The doctor will insert a lighted tube through my urethra into my bladder in order to inspect the inside of the bladder"
d) The SNS has caused afferent arteries to constrict to decrease blood flow Pg. 846 Glomerular Filtration The afferent and the efferent arterioles are innervated by the sympathetic nervous system and are sensitive to vasoactive hormones, such as angiotensin II. 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. There is not enough information to conclude the kidneys are injured, the renal arteries are clotted, or the vagus nerve has been innervated.
15. An automobile accident client is brought to the emergency department in hypovolemic shock from internal bleeding. Nurses are closely monitoring urine output since a significant decrease signifies that: a) The vagus nerve has caused bradycardia, which decreases amount of blood reaching the kidneys b) The kidneys are probably injured c) Renal arteries are clogged with blood d) The SNS has caused afferent arteries to constrict to decrease blood flow
d) First void in morning Pg. 856 Urine Tests 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 (e.g., during the first urine specimen on arising in the morning).
16. 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) At noon c) Last void at night d) First void in morning
e) Client with history of chronic kidney failure Pg. 855 Erythropoietin Erythropoietin is a glycoprotein hormone that is produced by fibroblasts in the kidney and regulates the production of red blood cells in the bone marrow. Persons with end-stage kidney disease often are anemic because the kidneys can no longer produce erythropoietin. Impaired oxygenation of tissues due to cardiac or pulmonary disease stimulates the kidney to produce erythropoietin. A client whose recent wound is healing is likely not experiencing anemia related to loss of erythropoietin production. Some clients experience blood loss after surgery, but this should stimulate the kidney to produce more erythropoietin.
17. The nurse is assigned multiple clients with anemia. Which client may be experiencing a failure of the body to produce erythropoietin and thus may require supplemental injections of this hormone? a) Client with a recent wound that bled a large amount but is now healing well b) Client who recently had surgery and is scheduled for a follow-up visit c) Client living at a high altitude d) Client with impaired oxygenation related to chronic obstructive pulmonary disease (COPD) e) Client with history of chronic kidney failure
a) Urea Pg. 846 Tubular Reabsorption and Se Sodium, potassium, and glucose are reabsorbed using primary or secondary active transport mechanisms, whereas urea and water may be passively absorbed along concentration gradients.
18. Which component of glomerular filtrate can passively cross the tubular epithelial cell membrane? a) Urea b) Sodium c) Potassium d) Glucose
b) Transform vitamin D to its active form Pg. 856 Summary Concepts 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.
19. Clients with CKD are at risk for demineralization of their bones since they are no longer able to: a) Excrete bicarbonate effectively b) Transform vitamin D to its active form c) Synthesize erythropoietin d) Stimulate bone osteoclastic production
d) Urine specific gravity of 1.020 Pg. 856 Urine Tests Normal urine specific gravity ranges from 1.010 to 1.025. Glucose and casts are normally absent, and albumin is normally present in only scant amounts.
2. A client has a routine urine sample during an annual checkup. Which result is an expected finding in a healthy individual? a) Presence of urinary casts b) Low to moderate amount of glucose in the urine c) Presence of moderate amounts of albumin with the absence of other proteins d) Urine specific gravity of 1.020
a) Cytoscope Pg. 858 Cytoscopy and Ureteroscopy Cystoscopic examinations can be used for direct visualization of the urethra, bladder, and ureters. Ultrasonography can be used to determine kidney size, and renal radionuclide imaging can be used to evaluate the kidney structures. Radiologic methods, such as excretory urography, provide a means by which kidney structures such as the renal calyces, pelvis, ureters, and bladder can be outlined. Other diagnostic tests include CT scans, MRI, radionuclide imaging, and renal angiography.
3. Which diagnostic study would be effective in determining direct visualization of the bladder and ureters? a) Cystoscope b) MRI c) Renal angiography d) Ultrasonography
b) Increased levels of uric acid in the blood cause gout Pg. 854 Uric Acid Elimination Uric acid is a product of purine metabolism. High blood levels of uric acid (hyperuricemia) can cause gout, and excessive urine levels can cause kidney stones.
4. When teaching the client with gout about the cause of the disease, which cause should the nurse relate? a) High blood pressure causes gout b) Increased levels of uric acid in the blood cause gout c) Retention of sodium can cause gout d) Urea, in the form of blood urea nitrogen, causes gout
c) The damaged kidney is unable to produce erythropoietin Pg. 855 Erythropoietin 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.
5. A client with end-stage kidney disease has developed anemia. The nurse teach this client that the reason anemia has developed is: a) Medications taken for kidney disease destroy the red blood cells b) Activation of vitamin D cannot occur when kidneys are damaged c) The damaged kidney is unable to produce erythropoietin d) Clients with kidney disease must avoid consuming iron
b) Glomerular filtration rate (GFR) Pg. 857 Glomerular Filtration Rate The GFR is the preferred method for evaluating kidney function. BUN levels can fluctuate based on factors such as fluid volume status and protein intake. Urine output can be normal or high in clients with an acute kidney injury and not reflective of kidney functioning. Creatinine alone is not an accurate reflection of kidney function.
6. A client is hospitalized and being treated for an acute kidney injury. Which information is most useful to the nurse while evaluating for improvement in kidney function? a) Blood urea nitrogen (BUN) b) Glomerular filtration rate (GFR) c) 24-hour intake and output d) Creatinine level
d) Significant decrease in urine output due to decrease in renal blood flow Pg. 851 Neural and Humoral Control Mechanisms 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.
7. 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) Excess output of blood-tinged urine b) An increase in GFR due to relaxation of the afferent arterioles c) Complaints of flank pain rotating around the abdominal muscles d) Significant decrease in urine output due to decrease in renal blood flow
c) Thiazide diuretics Pg. 855 Drug Elimination Because of its effect on uric acid secretion, aspirin is not recommended for treatment of gouty arthritis. Thiazide and loop diuretics also can cause hyperuricemia and gouty arthritis, presumably through a decrease in ECF volume and enhanced uric acid reabsorption.
8. Which medication may be responsible for a client developing increased uric acid levels by decreasing ECF volume? a) Antacids b) Vitamin C c) Thiazide diuretics d) Penicillin antibiotics
b) "Often when an abnormal substance shows up in a urine test, a 24-hour urine collection is needed to determine exactly how much is present in your urine" Pg. 856 Urine Tests 24-hour urine tests are often used to quantify the amount of substances, such as proteins, that an individual's kidneys are spilling. Single urine samples are able to assess more parameters than just the presence of bacteria, and they are sufficient in quantity to detect numerous substances such as glucose.
9. A client in the hospital is frustrated at the inconvenience of having to collect his urine for an entire day and night as part of an ordered 24-hour urine-collection test. The client asks the nurse why the test is necessary since the client provided a single urine sample 2 days prior. How could the nurse best respond? a) "Current lab tests aren't able to detect the small quantities of most substances contained in a single urine sample" b) "Often when an abnormal substance shows up in a urine test, a 24-hour urine collection is needed to determine exactly how much is present in your urine" c) "Only a longer-term test is able to show whether your kidneys are letting sugar spill out into your urine" d) "A single urine sample lets your care team determine if there are bacteria in your urine, but other tests of urine chemistry need a longer term view"