Ex5 Diuretics Flashcards
Acetazolamide
Carbonic anhydrase inhibitor
MOA Acetazolamide
inhibits carbonic anhydrase in proximal tubule
Clinical uses Acetazolamide
Diuresis
Chronic open-angle glaucoma
Metabolic Alkalosis
Acetazolamide clearance
via kidneys
Acetazolamide onset, peak, duration
onset/peak/duration - fast
duration – 4hours
How should Acetazolamide be adjusted for renal patients?
CrCl <10 = avoid
CrCl 10-50 = one dose will correct alkalosis
Acetazolamide AEs
Metabolic Acidosis (be careful to OVERcorrect alkalosis)
Hyperchloremia
Hypotension
Hypokalemia/natremia/phosphatemia/magnesemia/calcemia
Avoid Acetazolamide with
NS - could worsen hyperchloremic acidosis
Loop diuretics
ethacrynic acid
furosemide
bumetadine
Clinical uses of loop diuretics
diuresis (heart/liver/renal failure) HTN acute pulm edema hyperkalemia hyperphosphatemia, hypercalcemia
Ethacrynic Acid IV Onset, Peak, Duration
Fast
O: 5min
P: 15min
D: 2h
Severe sulfa allergy in patient who needs diuresis – tx?
Ethacrynic Acid
Fast rates of IVP loop diuretics may cause
ototoxicity (limit to 10mg/min)
Most diuretics are excreted via
kidneys
Dialyzable diuretics
Acetazolamide (HD: 20-50%)
Ethacrynic Acid: minimal
Mannitol (14% with 6h session)
Triamterene: Yes
Renal impairment - how to dose diuretics?
MUCH larger dose (i.e. Furosemide=100mg)
Torsemide careful with?
Duration: 6-8h; only PO
Highest risk of ototoxicity
Ethacrynic Acid
Braking Phenomenom
Loop diuretic tolerance
-hypertrophy in renal tubule/reabsorbs what was blocked
Management of loop diuretic tolerance
- thiazide diuretics
- continuous infusion (vs. IVpush)
- increased dose
Loop Diuretic Equivalent dosing: Bumex 1mg IV = Furosemide _____IV
20mg
Loop Diuretic Equivalent dosing: Bumex 1mg IV = Ethacrynic Acid _____IV
50mg
Loop Diuretic Equivalent dosing: Bumex 1mg IV = Bumex _____PO
1mg
Loop Diuretic Equivalent dosing: Bumex 1mg IV = Torsemide _____PO
20mg