Diuretics

Front 1

What are the functional regions of the nephron?

Back 1

1. glomerulus
2. proximal convoluted tubule
3. Loop of Henle
4. distal convoluted tubule

Front 2

Which basic kidney function is most effected by diuretics?

Back 2

Maintenance of extracellular fluid (ECF)

Front 3

Which part of the nephron is responsible for filtration?

Back 3

glomerulus

Front 4

In which way do most diuretics work within the nephron?

Back 4

Interfering with absorption

Front 5

Where in the nephron does active secretion of waste products take place?

Back 5

proximal convoluted tubule

Front 6

Where is about 65% of the filtered sodium and chloride reabsorbed?

Back 6

Proximal convoluted tubule

Front 7

What percentage of filtered sodium and chloride is reabsorbed in the ascending limb of the Loop of Henle?

Back 7

20%

Front 8

Which hormone determines the final concentration of urine?

Back 8

Antidiuretic hormone

Front 9

What are the adverse effects of diuretics on fluid balance?

Back 9

1. hypovolemia
2. acid-base imbalance
3. altered electrolyte levels

Front 10

What are the four categories of diuretic drug?

Back 10

1. high-ceiling loop diuretics (furosemide)
2. thiazide diuretics (hydrochlorothiazide)
3. osmotic diuretics (mannitol)
4. potassium-sparing diuretics (spironolactone)

Front 11

Which diuretic drug category is most effective?

Back 11

Loop diuretics

Front 12

Which part of the Loop of Henle does Furosemide act in?

Back 12

thick segment of the ascending limb

Front 13

Furosemide prevents active/passive reabsorption of sodium and chloride.

Back 13

passive

Front 14

Which conditions justify the use of a loop diuretic like Furosemide?

Back 14

1. pulmonary edema from CHF
2. unresponsive edema of cardiac, hepatic or renal origin
3. hypertension that cannot be controlled with other diuretics

Front 15

Why are loop diuretics effective when thiazide diuretics are not?

Back 15

It can promote diuresis even when renal blood flow and glomerular filtration rate are low.

Front 16

Which adverse effects are specific to loop diuretics?

Back 16

1. hyponatremia
2. hypochloremia
3. Dehydration
4. Hypotension
5. Hypokalemia
6. Ototoxicity

Front 17

If serum potassium falls below _____ mEq/L, fatal dysrhythmias may result.

Back 17

3.5

Front 18

When using loop diuretics with Digoxin, what must be done, and why?

Back 18

Routine potassium monitoring. Because loop diuretics can cause hypokalemia, the risk of Digoxin toxicity increases.

Front 19

Which drug can increase the risk of ototoxicity when a patient is on loop diuretics?

Back 19

aminoglycoside antibiotics (gentamicin)
aspirin

Front 20

Which drugs can be given with a loop diuretic such as Furosemide to help reduce the risk of hypokalemia?

Back 20

Potassium-sparing diuretics such as spironolactone

Front 21

What are the similarities between loop and thiazide diuretics?

Back 21

they increase renal excretion of sodium, chloride, potassium and water.

Front 22

Do thiazides promote more or less diuresis than loop diuretics?

Back 22

Less.

Front 23

What causes thiazides to be ineffective?

Back 23

low glomerular filtration rate (under 15 to 20 mL/min)

Front 24

What is the main use for thiazide diuretics? What else are they the preferred drug for?

Back 24

essential hypertension

edema associated with mild to moderate heart failure or hepatic or renal disease

Front 25

What are the adverse effects of thiazide diuretics?

Back 25

Hyponatremia, hypochloremia, dehydration, hypokalemia

Front 26

What are the advantages of a potassium-sparing diuretic?

Back 26

1. they produce a modest increase in urine production
2. they produce a substantial decrease in potassium excretion

Front 27

What are the two subcategories of potassium-sparing diuretic?

Back 27

1. aldosterone antagonists
2. nonaldosterone antagonists

Front 28

Where do potassium-sparing diuretics perform their actions?

Back 28

in the distal nephron

Front 29

Potassium-sparing diuretics promote the retention of __________ and the excretion of __________.

Back 29

potassium
sodium

Front 30

How long does it take for Spiranolactone to act?

Back 30

48 hours

Front 31

What are potassium-sparing diuretics used to treat symptoms of?

Back 31

Hypertension, edema, and heart failure

Front 32

What are the adverse effects of potassium-sparing diuretics?

Back 32

hyperkalemia, endocrine effects (gynecomastia, mentrual irregularities, impotence, hirsutism)

Front 33

What medications must potassium-sparing diuretics never be combined with?

Back 33

potassium supplements, salt substitutes, other potassium-sparing diuretics

Front 34

What percentage of the water, electrolytes, and nutrients filtered at the glomerulus undergo reabsorption?

Back 34

99%

Front 35

The amount of diuresis produced is directly related to what?

Back 35

The amount of sodium and chloride reabsorption blocked.

Front 36

Which drugs affect the greatest amount of solute reabsorption and diuresis?

Back 36

Diuretics that work early in the nephron

Front 37

Which group of diuretics must not be used when pregnant or lactating?

Back 37

Thiazides

Front 38

Why do loop diuretics cause hypotension?

Back 38

They decrease blood volume and relax venous smooth muscle

Front 39

Is hearing loss caused by loop diuretics reversible?

Back 39

Yes