CH 32 NCLEX Qs
BNP (brain natriuretic peptide)
-BNP is ordered to help determine HF and is a more sensitive test than ANP. It is a neurohormone secreted primarily by cardiac ventricles and increases in response to volume expansion and pressure overload.
ANP (atrial natriuretic peptide)
-Produce by atrial auricles -Target: kidneys -Effect: blocks effect of aldosterone, decreases sodium reabsorption, lowers blood pressure Secreted in response to excess blood volume in the heart, promotes salt and thus water excretion. release with increase BP - kidneys excrete more Na+ and water, thus decrease BP
Diuretics
Work by blocking reabsorption of sodium p.975
The physician has prescribed a thiazide diuretic for a client. The nurse anticipates that the medication will: a) Block the tubular reabsorption of sodium b) Decrease the glomerular filtration rate (GFR) c) Activate the renin-angiotensin system d) Release antidiuretic hormone (ADH)
a) Block the tubular reabsorption of sodium The thiazide diuretics, which are widely used to treat disorders such as hypertension, block sodium reabsorption in renal tubules and enhance the active reabsorption of calcium into the blood via the calcium-sodium exchange transport mechanism. If a client experienced a decrease in circulatory volume, this would activate the renin-angiotensin system, decrease the GFR, or release ADH.
Which of the following occurrences is most likely to cause increased urination? a) Decrease in anti-diuretic hormone b) Increase secretion of aldosterone c) Decrease in glomerular filtration rate d) Activation of angiotensin
a) Decrease in anti-diuretic hormone Increased urination or polyuria is caused by low levels of ADH which stimulates the kidneys to absorb more water. The other options do not have this physiological affect.
The major sites where aldosterone exerts its action on sodium reabsorption and potassium regulation occur in which tubule location? a) Late distal and cortical collecting tubule b) Thin ascending tubule and the thick descending tubule c) Juxtamedullary area and the elbow-diluting segment of distal tubule d) Proximal tubule and a thin descending segment of tubule
a) Late distal and cortical collecting tubule The late distal-convoluting and the cortical-collecting tubules are the sites of aldosterone action on sodium and potassium reabsorption. The thin ascending and thick ascending loops of Henle use the cotransport of sodium, potassium, and chloride. The proximal tubule reabsorbs sodium and water in equal proportions, in contrast to the thin descending loop (main site of water loss from filtrate). The elbow segment of the loop of Henle has the highest filtrate osmolality.
A nurse is teaching a client about the functions of the kidney. Which would be the most appropriate information for the nurse to provide? Select all that apply. a) Regulates blood pressure through the renin-aldosterone mechanism b) Maintains homeostasis of red blood cells by production of estrogen c) Eliminates metabolic wastes d) Regulates osmolality of intracellular fluid through action of antidiuretic hormone (ADH) e) Regulates calcium and phosphorus conservation and elimination f) Regulates pH of body fluids through reabsorption and conservation
a) Regulates blood pressure through the renin-aldosterone mechanism c) Eliminates metabolic wastes e) Regulates calcium and phosphorus conservation and elimination f) Regulates pH of body fluids through reabsorption and conservation
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) Urinary tract infection b) Abnormal glomeruli filtration c) Decrease in antidiuretic hormone d) Poor fluid intake
b) Abnormal glomeruli filtration Urine tests for proteinuria are used to detect abnormal filtering of albumin by the glomeruli or defects in its reabsorption in the renal tubules. A decrease in antidiuretic hormone would result in increased output; poor fluid intake would produce concentrated urine; a urinary tract infection would cause white blood cells to be in the urine.
An adult has a serum sample taken to evaluate the BUN-creatinine ratio. Select the result that indicates a normal test a) BUN 40 mg/dL to creatinine 2 mg/dL b) BUN 10 mg/dL to creatinine 1 mg/dL c) BUN 30 mg/dL to creatinine 2.5 mg/dL d) BUN 25 mg/dL to creatinine 1 mg/dL
b) BUN 10 mg/dL to creatinine 1 mg/dL The BUN-creatinine ratio is approximately 10:1. The other results, ratios greater than 15:1, represent prerenal conditions, such as congestive heart failure and upper gastrointestinal bleeding, that produce an elevation in BUN not creatinine.
When caring for a client with dehydration, the nurse anticipates the client will have an alteration in which of these substances in the blood? a) Uric acid b) Blood urea nitrogen c) Erythropoietin d) Bicarbonate
b) Blood urea nitrogen During periods of dehydration, the blood volume and GFR drop, and BUN levels increase. The renal tubules are permeable to urea, which means that the longer the tubular fluid remains in the kidneys, the greater is the reabsorption of urea into the blood.
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) Potassium: 3.4 mEq/L b) Creatinine: 10.6 mg/dL c) Sodium: 148 mEq/L d) Blood urea nitrogen: 20.0 mg/dL
b) Creatinine: 10.6 mg/dL 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.
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) The normal kidney produces an average 3000 ml of urine daily. b) The kidneys should produce about 1.5 liters of urine each day. c) The kidneys should produce a minimum of 10 ml/hour over one day. d) This represents normal urinary output for 24 hours.
b) The kidneys should produce about 1.5 liters of urine each day. The kidneys normally produce approximately 1.5 L or 1500 ml of urine each day.
Gout and the development of kidney stones are often attributed to high levels of what compound? a) Urea b) Uric acid c) Albumin d) Protein
b) Uric acid High blood levels of uric acid can cause gout and excessive urine levels can cause kidney stones. High albumin, urea, and protein levels can be indicative of renal disease, but are not specifically related to gout and kidney stones the way uric acid is.
The nurse is analyzing the results of a client's urinalysis. Which of these results require the nurse to follow up as they represent abnormal results? Select all that apply. a) Leukocyte esterase negative b) Specific gravity 1.010 c) Bilirubin positive d) Urine amber color e) Casts present
c) Bilirubin positive e) Casts present The following results should appear in the normal urinalysis: Color: yellow amber; appearance: clear to slightly hazy, color yellow amber; specific gravity: 1.005-1.025; bilirubin: negative; casts - negative; leukocyte esterase: negative.
Which condition causes an elevation in the level of blood urea nitrogen (BUN)?\ a) Pituitary disease b) Excessive fluid intake c) Gastrointestinal bleeding d) Heart disease
c) Gastrointestinal bleeding Urea is formed in the liver as a by-product of protein metabolism and is eliminated entirely by the kidneys. Therefore, the BUN is related to the GFR but, unlike creatinine, it also is influenced by protein intake, gastrointestinal bleeding, and hydration status. In gastrointestinal bleeding, the blood is broken down by the intestinal flora, and the nitrogenous waste is absorbed into the portal vein and transported to the liver, where it is converted to urea. Excessive fluid intake, pituitary disease, or heart disease would not contribute to an increased level of blood urea.
The nurse would be most concerned when the glomerular filtrate contains: a) Sodium b) Water c) Protein d) Potassium
c) Protein The glomerular filtrate has a chemical composition similar to plasma, but it contains almost no proteins because large molecules do not readily cross the glomerular wall. Potassium, sodium, and water would be filtered.
Which diuretic acts by preventing sodium chloride reabsorption in the distal convoluted tubule? a) Osmotic diuretics b) Loop diuretics c) Thiazide diuretics d) Potassium sparing diuretics
c) Thiazide diuretics Thiazide diuretics act by preventing the reabsorption of sodium in the distal convoluted tubule.
Which diagnostic study would be effective in determining direct visualization of the bladder and ureters? a) MRI b) Ultrasonography c) Renal angiography d) Cystoscope
d) Cystoscope 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
The nurse is caring for a client with a condition of deficiency of antidiuretic hormone (ADH). When assessing the client, which of these findings does the nurse anticipate? a) Retention of chloride b) Retention of sodium c) Low blood pressure d) Excessive urine output
d) Excessive urine output 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.
A nurse is administering spironolactone (Aldactone) to a client. Which of the following electrolyte imbalances should the nurse monitor for? a) Hypocalcemia b) Hypophosphatemia c) Hypernatremia d) Hyperkalemia
d) Hyperkalemia The aldosterone antagonists, also called potassium-sparing diuretics, reduce sodium reabsorption and decrease potassium secretion in the late distal tubule and cortical-collecting tubule site regulated by aldosterone. Because potassium secretion is linked to sodium reabsorption in this segment of the tubule, these agents are also effective in reducing potassium excretion and may, in some cases, cause severe hyperkalemia.
The nurse is caring for a client with heart failure and left atrial enlargement. Which of these physiologic consequences does the nurse anticipate when atrial natriuretic peptide is released due to atrial stretch? a) Deamination of ammonia b) Retention of hydrogen ions c) Excretion of hydrogen ions d) Inhibition of aldosterone
d) Inhibition of aldosterone ANP is a hormone believed to have an important role in salt and water excretion by the kidney. It is synthesized in muscle cells of the atria of the heart and released when the atria are stretched, which results in an increase in renal blood flow and GFR. ANP inhibits aldosterone secretion by the adrenal gland and sodium reabsorption from the collecting tubules through its action on aldosterone and through direct action on the tubular cells.
Mannitol (Osmitrol) has been ordered for a patient with increased intracranial pressure. The nurse plans to administer this drug using which of the following methods? a) Orally b) Subcutaneous injection c) Intramuscular injection d) Intravenously
d) Intravenously Mannitol, is used mainly to reduce increased intracranial pressure but is occasionally used to promote prompt removal of toxins. Because it is not absorbed, mannitol must be given intravenous to act as a diuretic.
In the presence of aldosterone in the distal tube, what action would occur? a) Sodium would not be reabsorbed. b) There would be no change in sodium. c) Sodium would be excreted in the urine. d) The urine would be nearly sodium free.
d) The urine would be nearly sodium free. In the presence of aldosterone, almost all the sodium in the distal tubular fluid is reabsorbed, and the urine is sodium free. In the absence of aldosterone, virtually no sodium is reabsorbed from the distal tubule so it would not be excreted.
