Flashcards in Chapter 21 Deck (30)
2.The individual units that carry out the work of the kidneys are called
The individual units that carry out the work of the kidneys are called nephrons. Each nephron contains several tubules. Capillaries are the smallest blood vessels found in the kidney and throughout the body. The kidney filters the blood to remove waste products.
1.The overall function of the kidneys is to
a.detect and eliminate body toxins.
b.maintain thermal homeostasis in the body.
c.maintain chemical homeostasis in the body.
d.control biochemical metabolism in the body.
The overall function of the kidneys is to maintain chemical homeostasis in the body. Biochemical metabolism is controlled within cells. Most toxins are neutralized in the liver. Thermal homeostasis is maintained by the skin and circulatory system.
3.Nephrotic syndrome causes loss of excessive amounts of
In nephritic syndrome, damage to the capillary walls in the glomerulus cause loss of protein. Excretion of fluid, sodium, and calcium are not excessive.
4.To control hypertension and edema, patients with nephrotic syndrome should restrict their intake of
To help control hypertension and edema, patients with nephritic syndrome should restrict their intake of sodium. Fluid restriction is not necessary because patients still produce urine. Protein and energy intakes should be adequate to prevent malnutrition and catabolism and replace urinary losses.
5.“Hidden” sources of sodium include
c.opaque salt shakers.
d.raw fruits and vegetables.
Hidden sources of sodium include mouthwash; if patients use mouthwash they should be instructed not to swallow it. Saltine crackers are coated with visible salt. Opaque salt shakers do not hide the fact that they contain sodium. Raw fruits and vegetables are low in sodium.
6.In a patient with acute renal failure, a sudden gain in weight is usually caused by
c.increased fat stores.
d.increased muscle mass.
In patients with acute renal failure, sudden increases in weight are usually caused by fluid retention. Most patients have very little appetite so they are unlikely to gain fat and they are inactive so they are unlikely to increase muscle mass. Also, gains in muscle mass and fat stores tend to be slow. Urea retention does not cause an increase in weight.
7.Retention of excessive amounts of waste products of protein metabolism in the blood is known as
Retention of excessive amounts of waste products of protein metabolism in the blood (including urea) is known as uremia. Oliguria is low output of urine. Jaundice is buildup of bilirubin in the blood due to liver disease or failure. Nephritis is an inflammation of the kidney.
8.For patients with renal failure, the best sources of protein are
d.essential amino acids.
For patients with renal failure, the best sources of protein are high-quality proteins. These are mostly animal proteins, but also include soy. Most vegetable protein has a lower biologic value. Patients with renal failure are able to digest whole proteins and do not need extra essential amino acids.
9.Protein needs of patients with acute renal failure who do not need dialysis are
a.lower than those of patients receiving hemodialysis.
b.the same as those of patients receiving hemodialysis.
c.higher than those of patients receiving hemodialysis.
d.dependent on the volume of urine produced.
Patients with acute renal failure who do not need dialysis have lower protein needs than patients receiving hemodialysis because hemodialysis patients lose protein during treatments. Protein is not lost in the urine and so protein needs are not affected by the volume of urine produced.
10.For patients in the oliguric phase of acute renal failure, fluid needs are
a.less than 1 L.
b.1 mL/kg body weight.
c.double the amount of output.
d.the amount of output plus 500 mL.
In the oliguric phase of acute renal failure, fluid needs are the amount of output (urine, vomitus, and diarrhea) plus 500 mL per day. The amount cannot be based on an arbitrary figure or body weight because the ability of the kidneys to produce urine varies greatly between patients.
11.A gradual, irreversible loss of kidney function is called
a.acute renal failure.
b.chronic renal failure.
d.dialysis-dependent renal failure.
Gradual, irreversible loss of kidney function is called chronic renal failure. Acute renal failure is characterized by an abrupt loss of renal failure and is often reversible. Nephrotic syndrome is caused by damage to the glomerulus and is also often reversible. Patients with chronic renal failure often become dependent on dialysis, but loss of kidney function may progress gradually for several years before dialysis becomes necessary.
12.Before development of end-stage renal disease, nutrition therapy for patients with chronic renal failure focuses on
a.limiting intakes of sodium and fluid.
b.limiting foods that produce toxic metabolic by-products.
c.providing sufficient protein to prevent secondary complications.
d.providing adequate energy, protein, and nutrients to promote recovery.
Before development of end-stage renal disease, nutrition therapy for patients with chronic renal failure focuses on limiting foods that produce toxic metabolic by-products; this reduces the burden on the kidneys. Sodium and fluid intakes do not need to be limited at this stage. Protein intake should be limited to the amount needed by the body because breakdown of excess protein produces toxic metabolic by-products. Chronic kidney disease is irreversible so provision of adequate nutrients will not promote recovery, although it is important to maintain good nutritional status.
13.The National Renal Diet
a.provides carefully calculated menus for patients with chronic renal failure.
b.provides flexible meal planning tools for patients with chronic renal failure.
c.provides lists of foods that are acceptable for patients with chronic renal failure.
d.allows patients with chronic renal failure to select foods without the help of a registered dietitian.
The National Renal Diet provides flexible meal planning tools for patients with chronic renal failure. Food intake needs to be tailored to individual preferences and lifestyles, so menus are not provided. It still requires the help of a registered dietitian to develop a personalized meal plan. There are no “acceptable” and “unacceptable” foods for patients with chronic renal failure, but the National Renal Diet helps patients choose appropriate portion sizes of foods high in nutrients that must be limited.
14.Of the following, the meal that would be best to include as part of a renal diet plan is
a.cheese omelet with biscuits.
b.baked chicken with rice and green beans.
c.bean burrito with tortilla chips and salsa.
d.peanut butter sandwich on whole wheat bread.
The meal that would fit best within a renal diet plan is baked chicken with rice and green beans. This provides high-quality protein without excessive sodium, potassium, or phosphorus. The omelet provides high-quality protein from eggs and cheese, but cheese is high in phosphorus and biscuits are higher in sodium than other breads. The beans in the burrito provide lower-quality protein and are high in phosphorus; also, the tortilla chips are high in sodium (unless they are unsalted). Peanut butter provides lower-quality protein and is high in phosphorus; whole wheat bread is also high in phosphorus.
15.A food that is restricted in patients who are receiving hemodialysis because it is high in phosphorus is
Milk is restricted in patients who are receiving hemodialysis because it is high in phosphorus. Bananas and potatoes are high in potassium, not phosphorus. Eggs are not high in phosphorus and provide a good source of high-quality protein.
16.Medications used to reduce serum phosphorus levels should be taken
d.1 hour after meals.
Phosphate binders, used to reduce serum phosphorus levels, should be taken with meals. This allows the medications to bind the phosphorus in the food. They are ineffective if taken with fluids only, between meals, or 1 hour after meals.
17.Patients with chronic renal failure often need supplements that contain an active form of vitamin
Patients with chronic renal failure often need supplements that contain an active form of vitamin D because the kidney fails to complete the final step in activating vitamin D. Supplements of fat-soluble vitamins (including A and K) are not needed; vitamin A toxicity has sometimes developed in hemodialysis patients. Supplements of vitamin C and other water-soluble vitamins may be needed but do not need to be given in an active form.
18.In patients with chronic renal failure, inadequate production of the hormone erythropoietin causes
Erythropoietin stimulates bone marrow to produce red blood cells, so inadequate production in patients with chronic renal failure causes anemia. Uremia is caused by accumulation of nitrogenous waste products. Hypertension is caused by inadequate renin production. Fluid retention is caused by failure to produce urine and by sodium retention.
19.Patients treated with hemodialysis often require supplements containing
b.essential fatty acids.
Patients treated with hemodialysis often require supplements of water-soluble vitamins because of poor intake and losses during dialysis. Most patients do not need supplements of trace elements, essential fatty acids, and fat-soluble vitamins.
20.In peritoneal dialysis, the peritoneum serves as the
In peritoneal dialysis, the peritoneum serves as the dialysis membrane. It serves some, but not all of the functions of a nephron. Dialysate is instilled into the peritoneal cavity. Homeostasis is achieved by balancing food and fluid intake with dialysis.
21.The type of peritoneal dialysis in which the patient receives four of five exchanges of dialysate every day, each dwelling in the peritoneal cavity for about 4 hours, is known as _____ peritoneal dialysis.
The type of peritoneal dialysis in which the patient receives four or five exchanges of dialysate every day, each dwelling in the peritoneal cavity for about 4 hours, is called continuous ambulatory peritoneal dialysis.
22.Patients treated with peritoneal dialysis have higher dietary protein needs than those treated with hemodialysis because
a.more protein is lost into the peritoneal dialysate.
b.protein is needed for maintenance of the peritoneum.
c.patients treated with peritoneal dialysis tend to be more active.
d.peritoneal dialysis is a more efficient method of removal of nitrogenous waste.
Patients treated with peritoneal dialysis have higher dietary protein needs that those treated with hemodialysis because more protein is lost into the dialysate. Maintenance of the peritoneum does not significantly increase protein needs and patients are not necessarily more active. Peritoneal dialysis is not more efficient than hemodialysis for removing nitrogenous waste.
23.Patients treated with peritoneal dialysis have lower energy needs than those treated with hemodialysis because
a.hemodialysis increases metabolic rate.
b.peritoneal dialysis suppresses metabolic rate.
c.dextrose is absorbed from the peritoneal dialysate.
d.patients treated with peritoneal dialysis are less active.
Patients treated with peritoneal dialysis have lower energy needs than those treated with hemodialysis because dextrose is absorbed from the peritoneal dialysate. Hemodialysis does not increase metabolic rate and peritoneal dialysis does not suppress metabolic rate. Patients treated with peritoneal dialysis are not less active.
24.If blood phosphorus levels are elevated, patients may develop
Elevated blood phosphorus levels may lead to osteodystrophy (defective bone development). Anemia in patients with chronic renal disease is caused by failure to produce erythropoietin. Renal calculi are caused by various metabolic imbalances and by poor fluid intake. Osteoporosis is caused by long-term inadequate intakes of calcium and vitamin D and lack of weight-bearing exercise.
25.Patients with diabetes mellitus and chronic renal failure who are treated using peritoneal dialysis may have difficulty controlling their diabetes because
a.insulin is lost into the dialysate.
b.glucose is absorbed from the dialysate.
c.the combined food restrictions are so complex.
d.peritoneal dialysis causes taste changes and food aversions.
Peritoneal dialysis may cause difficulty with metabolic control for patients with diabetes mellitus because glucose is absorbed from the dialysate. Loss of insulin into the dialysate is not a problem. Combined food restrictions are somewhat complex, but do not make control of blood glucose levels more difficult. All patients with renal disease experience taste changes and food aversions, but these do not necessarily affect control of diabetes.
26.Immediately following renal transplantation, energy needs
a.are lower than normal.
b.are higher than normal.
c.fluctuate from day to day.
d.depend on nutritional status before surgery.
Immediately after a renal transplant, energy needs are higher than normal because of the stress from surgery and catabolism. They do not generally fluctuate from day to day and do not depend on nutritional status before surgery.
27.Steroid therapy may result in
d.increased protein needs.
Steroid therapy may cause glucose intolerance. Steroids do not cause lactose intolerance, hypertriglyceridemia, or increased protein needs.
28.Most renal calculi are composed of
The most common type of renal calculi is calcium oxalate. Cystine, struvite, and uric acid stones are less common.
29.The most important advice for preventing kidney stones is to
a.restrict dietary calcium intake.
b.increase dietary protein intake.
c.drink at least 10 to 12 cups of fluid daily.
d.achieve and maintain a healthy body weight.
The most important advice for preventing kidney stones is to drink at least 10 to 12 cups of fluid daily. Restricting dietary calcium intake is not necessary and may actually increase stone formation. Increasing dietary protein intake may increase stone formation. Body weight does not appear to be related to formation of kidney stones.