Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IC > Diuretics > Flashcards

Diuretics Flashcards

1
Q

Three basic renal fxns

A

filtration, reabsorption, secretion

-reabsorb substances that body needs, maintain acid-base balance, excrete waste and foreign products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

NaCl movement will result in

A

water movement- osmotic equilibrium

-increasing or decreasing Na+ reabsorption the kidney increases or decreases body fluid volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Diuretic drugs act by

A

blocking sodium and chloride reabsorption to inc osmotic pressure in tubules, which prevent osmotic reabsorption of water and increases urine volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Drugs acting early (loop diuretics) will produce

A

greatest diuresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Drugs acting late (potassium sparing diuretics) result in

A

weaker diuresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Clinical apps for diuretics

A

heart failure (loop diuretics), htn (thiazide diuretics), acute/chronic renal failure, nephrotic syndrome, cirrhosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Acetazolamide

A
  • BlocksNaHCO3 reabsorption, and blocks Na reabsorption
  • Effectiveness diminishes over several days because bicarbonate depletion enhances NaCl reabsorption
  • Mainly used to treat glaucoma because ciliary body secretes bicarbonate to increase intraocular pressure– acetazolamide will decrease pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Carbonic Anhydrase inhibitors

A

Act on proximal convuluted tubule
-Oral and opthalmic preparations available

Toxicities: hyperchloremic metabolic acidosis, alkalinizing urine can cause calcium phosphate salts. can cause renal potassium wasting because more Na reaches collecting duct, more K is secreted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sodium Glucose Cotransporter 2 (SGLT2) inhibitors

A

Not diuretics!

  • 3rd line tx for type 2 DM
  • Dapagliflozin, canagliflozin, empagliflozin
  • Inhibits Na, Glucose reabsorption to reduce hbA1c
  • Leads to weight loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Loop diuretics

A

Furosemide, butanemide, torsemide, ethacyrnic acid (not sulfonamide derivative)

  • Inhibits Na/K/2Cl cotransporter- decreased NaCl reabsorption
  • work on ascending limb of henle’s loop
  • Also, additional Mg, Ca excretion because lower K potential difference cannot drive Mg and Ca to be reabsorbed paracellularly (Ca will be reabsorbed in distal tubule, but Mg will be excreted leading to hypomagnesemia)
  • Most effective diuretics available
  • Eliminated by tubular secretion and filtration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Hypokalemia caused by loop diuretics

A

Inc delivery of Na to distal convoluted tubule–> enhances K and H secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Loop diuretics and renin release

A

Reduced NaCl reabsorption– more Na in tubular fluid–> reduced NaCl influx into macula densa –> inc secretion of prostaglandins–> increased renin secretion (from juxtaglomerular cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Clinical use of loop diuretics

A
  • relief pulmonary edema
  • Hypercalcemia
  • htn (only if thiazides do not work)
  • severe hyperkalemia (enhance K secretion)
  • acute renal failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Loop diuretics AE

A
  • ototoxicity (reversible) because Na/K/2Cl transporter in ear for transport for endolymph production in cochlea
  • hyperuricemia and gout attacks- hypovolemia associated inc uric acid reabsorption in proximal tubule
  • allergic reactions (more common with sulfonamides)
  • hypokalemia (can lead to arrythmias)
  • dehydration and hyponatremia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Thiazide and Thiazide like diuretics

A
  • names end in thiazide
  • All are sulfonamides
  • Inhibit Na/Cl- cotransport
  • Enhanced Ca2+ reabsorption bc of inc Na gradient across basolateral membrane in distal convoluted tubule
  • more effective antihtn in AA and elderly
  • can lead to hyperuricemia because secreted by same system as uric acid
  • inc K+ secretion in collecting duct- hypokalemia
  • reduce Ca2+ excretion by enhancing reabsorption (decreased Na+ in)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Thiazide like drugs

A

-Chlorthalidone, indapamide, metolazone, guinethazone

17
Q

Clinical uses for thiazides

A
  • htn at low dose
  • chf at higher dose second to loop diuretics
  • nephrolithiasis for hypercalciuria
  • nephrogenic diabetes insipidus to reduce polyuria and polydipsia (not known how it works bc pts already lose a lot of water)
18
Q

AE for thiazides

A

hyperuricemia, hypokalemic metabolic alkalosis, hyperglycemia, hyperlipidemia, hyponatremia

  • allergic rxns- photosensitivity
  • hemolytic anemia, thrombocytopenia, acute necrotizing pancreatitis
  • weakness, fatigability, ED in elderly men
19
Q

Potassium sparing diuretics

A
  • Act on collecting tubule
  • Act on transport mechanisms that reabsorb Na (Na channel)- which is regulated by aldosterone
  • high aldosterone, more Na reabsorbed, which causes K to be secreted
  • both classes of drugs cause reduced K secretion
  • weak diuretics, used in combination with loop or thiazide to reduce hypokalemia
20
Q

K sparing diuretics clinical uses

A

-used for chf, primary mineralocorticoid hypersecretion (ACTH), secondary aldosteronism

21
Q

aldosterone antagonists

A
  • potassium sparing
  • eplerenone, spironolactone
  • aldosterone binds to receptors and increases Na+ reabsorption and K, H secretion– this mechanism will be blocked
22
Q

Na channel blockers

A
  • potassium sparing
  • Amiloride, triamterene
  • block apical Na+ channels to cause loss of potential (decreases driving force for K secretion) and reduce K and H secretion
23
Q

Potassium sparing duretics toxicity

A

-hyperkalemia, hyperchloremic metabolic acidosis (H secretion reduced), gynecomastia (spironolactone), kidney stones with triamterene

24
Q

Vaptans: ADH antagonists

A
  • conivaptam, tolvaptan
  • ADH regulates number of aquaporins in luminal mmebrane of collecting tubule
  • Dilutes urine
  • vasopressin receptor antagonists
  • inhibit effects of ADH
  • Used to manage inappropriate ADH secretion, and added to drug regimen of CHF when ADH elevated
  • Na needs to be monitored closely
25
Q

Osmotic diuretics

A
  • Mannitol
  • Filtered by glomerulus but not reabsorbed–> inc osmolarity of ultrafiltrate and prevents water reabsorption–> promotes water diuresis
  • used for emergency situations- reduce intracranial pressure
  • IV
  • severe dehydration, hypernatremia, headache, nausea, vomiting
26
Q

In HF, diuretics will

A

reduce ECF volume–> reduce preload–> reduce cardiac work
-first choice- furosemide (ethacrynic acid if allergic to sulfonamides)
-

27
Q

Htn, diuretic use

A

Thiazides

  • chlorathalidone (longer 1/2 life) at low dose for htn (high dose for diuresis)
  • monotherapy for mild to moderate htn
28
Q

Which diuretic for GFR >30 ml/min

A

thiazide diuretics

29
Q

Which diuretic for GFR <30 ml/min

A

loop diuretics

IC (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions