Patho II PrepU Chp. 34

Several urine tests can be useful in establishing a diagnosis of acute renal failure (ARF). The nurse must consider that fractional excretion of sodium can be particularly affected by administration of which type of drug? a. Diuretics b. Beta-adrenergic blockers (beta-blockers) c. Calcium channel blockers d. Sulfonylureas

a Diuretics, which directly affect renal excretion of sodium, can alter the fractional excretion of sodium. The other drug types listed do not affect this parameter of renal function.

The health care provider is reviewing laboratory results of a client. Select the diagnostic test that is considered the best measurement of overall kidney function. a. Glomerular filtration rate (GFR) b. Blood urea nitrogen (BUN) c. Urine albumin levels d. Serum creatinine levels

a GFR is the best overall measure of kidney function. GFR is usually estimated using the serum creatinine concentration. Creatinine, a by-product of muscle metabolism, is produced at a fairly constant rate, is freely filtered in the glomerulus, and is not reabsorbed in the renal tubules. Essentially all of the creatinine filtered by the kidneys is lost in the urine; therefore, serum creatinine is an indirect measure of GFR. Proteinuria serves as a key adjunctive tool for measuring nephron injury and repair. Urine normally contains small amounts of protein. Blood tests for BUN and creatinine provide information regarding the ability to remove nitrogenous wastes from the blood.

Creatinine measurement can assist in the diagnosis of acute renal failure (ARF). The nurse must consider that which factors can affect blood creatinine levels? Select all that apply. a. Age b. Gender c. Medications d. Socioeconomic status e. Muscle mass

a, b, c, e Age, gender, muscle mass, and some medications must be considered when blood levels of creatinine are used to diagnose ARF. Socioeconomic status should not affect creatinine levels unless it exerts severe impairment in general health and nutrition.

Which conditions have the potential to cause chronic kidney disease? Select all that apply. a. Hypertension b. Glomerulonephritis c. Cardiomyopathy d. Diabetes

a, b, d CKD can result from a number of conditions including diabetes, hypertension, glomerulonephritis as well as systemic lupus erythematosus, and polycystic kidney disease. These conditions slowly but steadily destroy renal tissue resulting in irreversible loss of function. Cardiomyopathies do not cause renal failure; they cause heart failure.

Phosphate excretion is impaired in chronic kidney disease (CKD), resulting in high serum phosphate levels and the development of phosphate crystals. Which manifestation of hyperphosphatemia should the nurse assess for? a. Azotemia b. Pruritus c. Asterixis d. Uremia

b The severe itching of pruritus results from the increased serum phosphate and phosphate crystals. The other answer selections are also manifestations of CKD but are not related to phosphate retention.

An 86-year-old client is being treated for dehydration and hyponatremia after curtailing fluid intake to prevent urinary incontinence. Given these findings, the nurse recognizes that this client is likely in what phase of acute kidney injury? a. Intrinsic b. Intrarenal c. Prerenal d. Postrenal

c Prerenal failure occurs when vascular volume and renal perfusion are decreased, for example by dehydration. Postrenal failure is the result of obstruction of urine outflow. Intrarenal (intrinsic) failure occurs when nephrons are destroyed.

A client with chronic kidney disease (CKD) has developed asterixis. The nurse knows that asterixis is: a. Burning sensation in feet b. Demyelination of nerve fibers c. Unsteady gait d. Dorsiflexion of hands and feet

d Asterixis, which is involuntary dorsiflexion of hands and feet, can develop as CKD worsens. Burning sensation in feet, unsteady gait and demyelination of nerves can also accompany CKD, but are not part of asterixis.

A client with chronic kidney disease (CKD) who is treated with hemodialysis reports poor sleep. For which complication common in clients with CKD should the nurse assess? a. restless legs syndrome b. autonomic neuropathy c. central neuropathy d. Raynaud syndrome

a Restless legs syndrome is a manifestation of peripheral nerve involvement and can be seen in as many as two-thirds of clients on dialysis. It often interferes with the client's ability to sleep, as the urge to move the legs interrupts sleep. Central neuropathy results from injury to the central nervous system injury such as with stroke and may result in pain syndromes. Raynaud syndrome is a condition of the vascular system that leads to vasoconstriction and dilation and is not associated with chronic kidney disease (CKD). Autonomic neuropathy can occur in clients with CKD, but it is not common nor associated with poor sleep.

Chronic kidney disease impacts many systems in the body. What is the most common hematologic disorder caused by CKD? a. Anemia b. Polycythemia c. Leukocytosis d. Erythrocythemia

a The most common hematologic disorder that accompanies CKD is anemia.

A geriatric nurse is caring for several clients. Which alterations in health should the nurse attribute to age-related physiologic changes? a. A 90-year-old woman's blood urea nitrogen (BUN) is rising. b. A 78-year-old woman's GFR has been steadily declining over several years. c. An 81-year-old man's serum creatinine level has increased sharply since his last blood work. d. A dipstick of an 80-year-old man's urine reveals protein is present.

b A gradual decrease in GFR is considered a normal age-related change. Increased creatinine or BUN would warrant follow up, as would the presence of protein in a client's urine.

Vitamin D metabolism is deranged in clients with chronic kidney disease (CKD). The nurse recognizes that which statement regarding vitamin D is correct? a. Calcitriol stimulates release of parathyroid hormone (PTH). b. Kidneys convert inactive vitamin D to its active form, calcitriol. c. Calcitriol blocks gastrointestinal absorption of calcium. d. Suppression of parathyroid hormone release is characteristic of CKD.

b Inactive vitamin D is converted to active calcitriol in the kidneys. Calcitriol enhances gastrointestinal absorption of calcium, and suppresses release of PTH. Elevated levels of PTH are characteristic of CKD as blood levels of phosphate rise and levels of calcium fall.

A client had excessive blood loss and prolonged hypotension during an extensive surgery. The client's postoperative urine output is sharply decreased and the blood urea nitrogen (BUN) is elevated. Which cause is most likely responsible for these abnormal findings? a. Acute bladder outlet obstruction b. Acute tubular necrosis c. Acute prerenal failure d. Acute intrarenal nephrotoxicity

b Ischemic acute tubular necrosis (ATN) occurs most frequently in persons who have major surgery with prolonged renal hypoperfusion—this directly damages the tubular epithelial cells with acute suppression of renal function. Nephrotoxic ATN is caused by toxic agents or drugs. Prerenal vasoconstriction is associated with acute-onset loss of renal output. Bladder (postrenal) obstruction would not affect the BUN, since it rarely causes renal failure.

The health care provider has prescribed an aminoglycoside (gentamicin) for a client. The nurse is aware that the client is at risk for: a. Chronic kidney disease b. Nephrotoxic acute tubular necrosis c. Postrenal failure d. Ischemic acute tubular necrosis

b Pharmacologic agents that are directly toxic to the renal tubule include aminoglycosides (e.g., gentamicin), chemotherapeutic agents such as cisplatin and ifosfamide, and radiocontrast agents. Nephrotoxic agents cause tubular injury by inducing varying combinations of renal vasoconstriction, direct tubular damage, or intratubular obstruction. Postrenal failure results from obstruction of outflow of the kidneys. CKD and its treatment can interfere with the absorption, distribution, and elimination of drugs. Acute tubular necrosis (ATN) occurs most frequently in clients who have major trauma, severe hypovolemia, overwhelming sepsis, trauma, or burns.

A client has an obstructive urine outflow related to benign prostatic hyperplasia. Due to the inability to excrete adequate amounts of urine, which type of renal failure should the nurse closely monitor for? a. Prerenal failure b. Postrenal failure c. Intrarenal failure d. Chronic renal failure

b Postrenal failure results from obstruction of urine outflow from the kidneys. The obstruction can occur in the ureter, bladder, or urethra. Due to the increased urine not being able to be excreted due to the obstruction, retrograde pressure occurs throughout the tubules and nephrons, which ultimately damages the nephrons. Prostatic hyperplasia is the most common underlying problem.

A client has experienced severe hemorrhage and is in prerenal acute kidney injury. The nurse anticipates the client's blood urea nitrogen (BUN) and serum creatinine laboratory results will be in which range? a. BUN elevates above 60 mg/dl (21.4 mmol/l) and creatinine decreases to less than 0.3 mg/dl (less than 27 µmol/l). b. The BUN-to-creatinine ratio is 20:1. c. Creatinine level increase to 5 mg/dl (442 µmol/l) and BUN decreases to 4 mg/dl (1.4 mmol/l). d. The BUN-to-creatinine ratio is 10:1.

b Prerenal injury is manifested by a sharp decrease in urine output and a disproportionate elevation of blood urea nitrogen (BUN) in relation to serum creatinine levels. The kidney normally responds to a decrease in the glomerular filtration rate (GFR) with a decrease in urine output. An early sign of prerenal injury is a sharp decrease in urine output. A low GFR allows more time for small particles such as urea to be reabsorbed into the blood. Creatinine, which is larger and nondiffusible, remains in the tubular fluid, and the total amount of creatinine that is filtered, although small, is excreted in the urine. Consequently, there also is a disproportionate elevation in the ratio of BUN to serum creatinine, from a normal value of 10:1 to a ratio greater than 20:1.

A nurse is assessing a client for early manifestations of chronic kidney disease (CKD). Which would the nurse expect the client to display? a. Terry nails b. Impotence c. Hypertension d. Asterixis

c Hypertension is commonly an early manifestation of CKD. The mechanisms that cause the hypertension are multifactorial: they include increased vascular volume, increased peripheral vascular resistance, decreased levels of renal vasodilator prostaglandins, and increased activity of the renin-angiotensin-aldosterone system. Impotence occurs in as many as 56% of males on dialysis. Terry nails are a dark band just behind the leading edge of a fingernail followed by a white band that occurs in the late stages. Asterixis, a sign of hepatic encephalopathy, is due to the inability of the liver to metabolize ammonia to urea.

The primary care provider for a newly admitted hospital client has added the glomerular filtration rate (GFR) to the blood work scheduled for this morning. The client's GFR results return as 50 mL/minute/1.73 m2. The nurse explains to the client that this result represents: a. concentrated urine. b. that the kidneys are functioning normally. c. a loss of over half the client's normal kidney function. d. a need to increase water intake.

c In clinical practice, GFR is usually estimated using the serum creatinine concentration. A GFR below 60 mL/minute/1.73 m2 represents a loss of one half or more of the level of normal adult kidney function. The GFR is not diagnostic for concentrated urine or the need to drink more water.

A client with stage 5 chronic kidney disease (CKD) is presenting with fever and chest pain, especially when taking a deep breath. The nurse detects a pericardial friction rub on auscultation. Which condition does the nurse suspect is common with this stage of kidney disease? a. Myocardial infarction b. Pulmonary edema c. Pericarditis d. Pulmonary embolism

c Pericarditis occurs in many people with stage 5 CKD due to the uremia and prolonged dialysis. The manifestations of uremic pericarditis resemble those of viral pericarditis with all its potential complications, including cardiac tamponade. The presenting signs include mild to severe chest pain with respiratory accentuation and a pericardial friction rub. Fever is variable in the absence of infection and is more common in dialysis than uremic pericarditis.

The nurse will monitor the client with chronic kidney disease (CKD) for which possible cardiovascular changes? Select all that apply. a. Impaired platelet function b. Hypophosphatemia c. Pericarditis d. Hypertension e. Heart failure

c, d, e Hypertension often occurs early in CKD due to several factors, including increased blood volume. Congestive heart failure and pericarditis can occur with more advanced CKD. Hyperphosphatemia develops as kidneys lose ability to excrete phosphate.

A client with a history of chronic kidney disease (CKD) is experiencing increasing fatigue, lethargy, and activity intolerance. The care team has established that the client's glomerular filtration rate (GFR) remains at a low, but stable, level. Which laboratory assessments will most likely be prescribed to help determine the cause of these new symptoms? a. Cystoscopy and ureteroscopy b. Assessment of pancreatic exocrine and endocrine function c. Blood work for white cells and differential d. Blood work for hemoglobin, red blood cells, and hematocrit

d Anemia is a frequent and debilitating consequence of CKD. The anemia may be due to chronic blood loss, hemolysis, bone marrow suppression due to retained uremic factors, and decrease in red cell production due to impaired production of erythropoietin and iron deficiency. Pancreatic function is not typically affected by CKD, and endoscopic examination is less likely to reveal a cause of fatigue. An infectious etiology is possible and would be informed by white cell assessment, but this is less likely than anemia given the client's report of symptoms.

The nurse is caring for a client with chronic renal failure who is on hemodialysis three times a week. In order to treat hyperphosphatemia and hypocalcemia, which medication will the nurse administer to decrease absorption of phosphate from the gastrointestinal tract? a. Epoetin alfa b. Lactulose c. Furosemide d. Calcium carbonate

d Early treatment of hyperphosphatemia and hypocalcemia is important to prevent or slow the development of skeletal complications. Milk products and other foods high in phosphorus content are restricted in the diet. Phosphate-binding antacids (aluminum salts, calcium carbonate, or calcium acetate) may be prescribed to decrease absorption of phosphate from the gastrointestinal tract.

A client diagnosed with CKD has begun to experience periods of epistaxis and has developed bruising of the skin and subcutaneous tissues. The nurse recognizes these manifestations as: a. Increased erythropoietin b. Decreased erythropoietin c. Increased platelet production d. Impaired platelet function

d The coagulation disorders of CKD are mainly caused by platelet dysfunction. Platelet counts may be slightly decreased, and the bleeding time is prolonged because of abnormal adhesiveness and aggregation. Clinically, persons with CKD can experience epistaxis (nosebleeds), menorrhagia (excessive menstrual bleeding), gastrointestinal bleeding, and bruising of the skin and subcutaneous tissues.

A 45-year-old female is being treated for ovarian cancer. Her treatment involves the chemotherapy agent cisplatin. The nurse should monitor the client for signs and symptoms of: a. glomerulonephritis. b. chronic renal failure (CRF). c. anemia. d. nephrotoxic acute tubular necrosis (ATN).

d The development of nephrotoxic acute tubular necrosis is due to the concentration effect of the kidney. The prolonged exposure to the chemotherapy agent causes the ATN. The disease state would progress faster than the CRF, and the glomerulus would not be affected. Anemia is not related to this type of chemotherapy.