Diuretics

Question 1

How much blood do the kidneys filter every minute?

Answer 1

About a half cup

Question 2

Why do the kidneys filter the blood?

Answer 2

To remove wastes and extra water to create urine

Question 3

What structure allows urine to flow from the kidneys to the bladder?

Answer 3

The ureters

Question 4

What makes up the urinary tract?

Answer 4

The kidneys, ureters, and bladder.

Question 5

What is tubular reabsorption?

Answer 5

The process by which the nephron removes water and solutes from the tubular fluid and returns them to the circulating blood.

Question 6

What is tubular fluid?

Answer 6

Pre-urine

Question 7

What is glomerular filtration rate (GFR)?

Answer 7

The rate at which the glomeruli filter the blood.

Question 8

What is a normal glomerular filtration rate?

Answer 8

120 ml water/minute

Question 9

How do we measure the glomerular filtration rate?

Answer 9

By measuring the creatinine clearance.

Question 10

What is clearance?

Answer 10

The complete removal of a substance from the blood.

Question 11

What is a diuretic?

Answer 11

A drug that increases the formation of urine in the body by changing the rate of excretion of specific electrolytes such as sodium and potassium.

Question 12

Why might you need a diuretic?

Answer 12

• edema due to congestive heart failure
• acute pulmonary edema
• liver disease (cirrhosis)
• renal disease
• hypertension
• conditions that cause hyperkalemia

Question 13

What is renal failure?

Answer 13

A decrease in the kidney’s ability to filter the blood to remove metabolic wastes. Can be acute or chronic.

Question 14

What percentage of nephrons need to be functional to maintain normal renal function.

Answer 14

50%

Question 15

What is the best marker for estimating kidney function?

Answer 15

Glomerular filtration rate

Question 16

What can acute renal failure cause the blood to retain?

Answer 16

Nitrogenous wastes

Question 17

What can cause acute renal failure?

Answer 17

Renal hypo-perfusion due to hypertension, dysrhythmias, heart failure, and shock.

Question 18

What can cause chronic renal failure?

Answer 18

Long-standing hypertension and diabetes.

Question 19

Is chronic renal failure reversible or irreversible?

Answer 19

Irreversible

Question 20

What is ascites?

Answer 20

When fluid collects in the spaces in the abdomen.

Question 21

How many different types of diuretics are there?

Answer 21

4

Question 22

Where do osmotic diuretics act?

Answer 22

In the proximal tubule

Question 23

How do osmotic diuretics work?

Answer 23

They pull water into the renal tubules from the surrounding tissues an inhibit tubular reabsorption of water and solutes, thus producing rapid diuresis.

Question 24

Why might you need osmotic diuretics?

Answer 24

• increase glomerular filtration rate to help prevent kidney damage during acute renal failure
• reduce intracranial pressure or cerebral edema
• reduce intraocular pressure
• promote excretion of toxic substances

Question 25

How much solute is excreted with osmotic diuretics?

Answer 25

65%

Question 26

Name an osmotic diuretic:

Answer 26

Mannitol (Osmitrol)

Question 27

How do loop diuretics work?

Answer 27

They prevent the reabsorption of sodium and chloride by blocking the sodium/potassium/chloride symporter in the loop of Henle.

Question 28

Where do loop diuretics act?

Answer 28

In the loop of Henle

Question 29

How much solute is excreted in loop diuretics?

Answer 29

20%

Question 30

Name an example of a loop diuretic:

Answer 30

Lasix (Furosemide)

Question 31

Should you take Lasix if you're pregnant?

Answer 31

No

Question 32

Should you take Lasix if you are allergic to sulfonamide antibiotics?

Answer 32

No

Question 33

What are the adverse effects of Lasix?

Answer 33

Hypovolemia, orthostatic hypotension, syncope, nausea, vomiting, ototoxicity.

Question 34

Should you take Digoxin at the same time as Lasix?

Answer 34

No

Question 35

What does Lasix do to you if you're also taking anti-hypertensives?

Answer 35

Increases hypotension even more

Question 36

What does Lasix do Insulin?

Answer 36

It diminishes it's effect

Question 37

When should you contact your physician about weight gain while taking Lasix?

Answer 37

If the weight gain is greater than 3 lbs in one day.

Question 38

What do potassium sparring diuretics do?

Answer 38

They increase urine output but promote the retention of K+

Question 39

What does aldosterone do?

Answer 39

It promotes the reabsorption of sodium and secretion of K+

Question 40

How do potassium diuretics work?

Answer 40

They are aldosterone antagonists so they prevent the reabsorption of water by preventing the reabsorption of Na+ but retain K+

Question 41

Where do potassium sparring diuretics work?

Answer 41

The collecting duct

Question 42

How much solute is excreted with potassium sparring diuretics?

Answer 42

5%

Question 43

Name an example of a potassium sparing diuretic

Answer 43

Spironolactone

Question 44

What are some of the side effects of spironolactone?

Answer 44

- amenorrhea - irregular menses - postmenopausal bleeding - muscle weakness - fatigue - bradycardia

Question 45

What type of drugs interact with Spironolactone

Answer 45

Antihypertensive drugs and potassium supplements

Question 46

How do thiazide diuretics work?

Answer 46

They block sodium nd chloride reabsorption at the distal tubule, reducing the reabsorption of water.

Question 47

Do thiazide diuretics promote ototoxicity?

Answer 47

No

Question 48

Where do thiazide diuretics act?

Answer 48

In the distal tubule.

Question 49

How much solute is excrete with thiazide diuretics?

Answer 49

10%

Question 50

Name a thiazide diuretic:

Answer 50

Chlorothiazide

Question 51

What drug interactions are there with chlorothiazide?

Answer 51

- antihypertensive drugs | - reduced effectiveness of coagulants, sulfonylureas, and antidiabetic drugs

Question 52

What are some symptoms of hypokalemia?

Answer 52

Fatigue, general malaise, muscle twitching, and cardiac irregularities.

Question 53

What foods are high in potassium?

Answer 53

Bananas, oranges, dates, apricots, raisins, broccoli, green beans, potatoes, meats, fish, and legumes.