Diuretic Actions Flashcards
Categories of Diuretics
Loop, Thiazide, CA Inhibitor, Thiazide-like
Common uses for diuretics
CHF, Hepatic Ascites, HTN, Nephrotic syndrome
CA inhibitors
Causes Bicarb to be retained in urine
Na can’t be exchanged for H, so Na in urine
Water follows, so diuresis
Urine is alkali if, get metabolic acidosis
CA inhibitor affect on urine
Increased volume, Na, K, and HCO3
Clinically useful for trapping chemicals in urine (not used on CPB)
Side effects of Acetzolamide (Diamox)
Glaucoma, high altitude sickness
Nickname for loop diuretics
High ceiling diuretics (dose response curve is nearly linear)
Yellow zipper drugs
Non potassium sparing
Chemical hemoconcentrator
Loop diuretic MOA
Block co transport of Na, K, 2Cl from tubular lumen back into circulation–So much left that nephron can’t compensate and it’s lost in urine
Increase RBF by expressing COX2 which produces prostaglandins (vasodilator)
Loop diuretic affect on urine
Increased Na, K, Ca, and volume
Perfusion uses of loop diuretics
Get rid of excess fluid
Get rid of excess K
Maintain UO and renal function
Loop diuretic side effects
Ototoxicity Hypokalemia Hypotension Hypomagnesemia Hyperuricemia
Nickname for Thiazide diuretics
Ceiling diuretics
Thiazide diuretic MOA
Blocks Na/Cl reabsorption on LUMINAL side of ascending loop and distal convoluted tubule
Increases RBF through COX2 prostaglandin synthesis
Only Thiazide available for parenteral use
Chlorothiazide
Thiazide diuretic effect on urine
Increased volume, Na, and K
Decreased Ca
Thiazide diuretic perfusion uses
Get rid of excess fluid
Decrease SVR
Increase Ca reabsorption
HTN
K sparing diuretic MOA
Prevent Na reabsorption and K excretion
Antagonize aldosterone
GFR layers of adrenal medulla
Glomerulosa: mineralocorticoids (aldosterone)
Fasciculata:glucocorticoids (cortisol)
Reticularis: androgens (testosterone precursors)
K sparing diuretic affect on urine
Increased Na and volume
Decreased K
Types of potassium sparing diuretics
Direct and indirect aldosterone antagonists
Indirect aldosterone antagonist MOA
Block Na channels used by aldosterone rather than aldosterone itself
Can be used in Addison’s patients (because have significant aldosterone)
Osmotic diuretic perfusion relevance
Maintain urine flow following acts renal injury
Decrease cerebral edema
1 rule when giving mannitol
Check bag for precipitated crystals
