Term
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Definition
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Term
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Definition
| increase in renal sodium excretion |
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Term
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Definition
| ability to inhibit sodium reabsorption & promote sodium excretion |
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Term
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Definition
| accumulation of excessive amounts of fluid in interstitial space; may generalized or localized |
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Term
| Main Factors influencing Fluid Movement in and out of capillaries |
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Definition
| intravascular hydrostatic pressure and plasma colloid osmotic pressure |
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Term
| Factors that increase transudation pressure and cause edema |
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Definition
| increase in intravascular hydrostatic pressure (arteriolar dilation, venular constriction, increased venous pressure, venous obstruction); decrease in colloid osmotic pressure (decreased production of plasma proteins, increased loss of plasma proteins, accumulation of osmotically active substances); impaired lymphatic drainage of interstitium (obstruction, radical mastectomy); renal retention of salt & water (kidney, liver, or heart dx); increased capillary permeability due to inflammatory substances (histamines, kinins) |
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Term
| Conditions that require Diuretics Therapeutically |
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Definition
| 1) CHF, 2) edema associated with liver disease, 3) edema associated with renal disease [nephrotic syndrome, acute renal failure]; 4) hypertension; 5) nephrolithiasis; 6) hypercalcemia; 7) nephrogenic diabetes insipidus; 8) glaucoma therapy & ocular surgery; 9) acute mountain sickness; 10) urinary excretion of toxins, OD tx, prevention of renal toxicity |
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Term
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Definition
| reabsorbs 67% of filtered water, Na, Cl, K, & other solutes; contains Na-K-ATPase, Na-H-Antiporter, and carbonic anhydrase (CA); area of action of carbonic anhydrase inhibitors such as acetazolamide; also allows for organic acid (anion) secretion & organic base (cation) secretion |
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Term
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Definition
| filters about 25% of filtered NaCl & K and 15% of H2O; contains Na-K-2Cl-symporter, Na-K-ATPase, K-Cl-symporter, and K ion channel; descending limb allows water reabsorption to occur, ascending limb is IMPERMEABLE to water; Furosemide inhibits the Na-K-2Cl-symporter |
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Term
| Distal Convoluted Tubule & Collecting Duct |
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Definition
| reabsorbs 7% (3% & 4% respectively) of filtered Na & 8-17% of water (vasopressin dependent); contains Na-Cl symporter (inhibited by Thiazide diuretics); principal cells of duct reabsorb Na (inhibited by amiloride & triamterene); aldosterone stimulates NaCl reabsorption and K secretion (inhibited by antagonists of aldosterone [Spirinolactone]); |
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Term
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Definition
| carbonic anhydrase inhibitor; sulfonamide derivative; secreted by organic acid (anion) secretion in proximal tubule; primary site of action is proximal tubule; also inhibits CA in other tissues; inhibits NaHCO3 reabsorption; inhibits production of aqueous humor & CSF; effectiveness is limited due to enhanced NaCl reabsorption by remaining tubule segments & decreased filtered bicarb as a result of metabolic acidodis |
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Term
| Therapeutic Uses of CAIs - acetazolamide (Diamox) |
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Definition
| glaucoma - decreases intraocular pressure by decreasing aqueous humor production; urinary alkalinzation; corrects metabolic acidosis; treats epilepsy; provides relief from mountain sickness; used to treat edema of various causes |
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Term
| Toxicities, ADRs, & C/I's of CAIs - acetazolamide (Diamox) |
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Definition
| hyperchloremic metabolic acidosis; urinary alkalization can lead to nephrolithiasis; hypokalemia; sulfonamide allergic hypersensitivity rxn; hepatic cirrhosis; in pts who are Na or K depleted |
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Term
| Osmotic Diuretics - mannitol (Osmitrol) |
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Definition
| chemically related to mannose; administered IV; drug remains in extracellular compartment; filtered by glomerulus with little tubular reabsorption; causes diuresis due to increase in osmotic pressure of glomerular filtrate leading to decreased reabsorption of water in nephron segments that are freely permeable to water & solutes; increases ECF volume by extracting water from intracellular stores & inhibiting renin release which increases renal blood flow; increases excretion of all electrolytes |
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Term
| Therapeutic Uses of mannitol (Osmitrol) |
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Definition
| oliguric acute renal failure; reduction of intraocular & intracranial pressure; urinary excretion of toxins/overdose tx/prevention of renal toxicity; used alone or in combo to treat edema |
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Term
| Toxicity, ADRs, & C/I's of Osmotic Diuretics - mannitol (Osmitrol) |
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Definition
| do NOT use in pts with heart failure or pulmonary congestion, severe renal dx, with cranial bleeding; hyponatremia; may lead to hyperglycemia |
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Term
| Loop Diuretics - furosemide (Lasix), ethacrynic acid (Edecrin) |
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Definition
| one is a sulfonamide derivative, the other a phenoxyacetic acid derivative; bound to plasma proteins that limits delivery to tubules by filtration; secreted by proximal tubule by organic acid (anion) secretion; act in thick ascending limb by blocking Na-K-2Cl-symporter; MOST POWERFUL diuretics; enhanced excretion of Na, Cl, K, H, Ca, & Mg |
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Term
| Therapeutic Uses of Loop Diuretics - furosemide (Lasix), ethacrynic acid (Edecrin) |
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Definition
| congestive heart failure & acute pulmonary edema; hypertension; hypercalcemia; edema of nephrotic syndrome; edema with liver cirrhosis |
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Term
| Toxicities, ADRs, & C/I's of Loop Diuretics |
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Definition
| hypotension, hypovolemia, hyponatremia; hypochloremic metabolic alkalosis; hypokalemia; exacerbation of Gout; ototoxicity; sulfonamide allergic hypersensitivity rxn (only 1 of 2 drugs) |
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Term
| Thiazide & Thiazide-like Diuretics - hydrocholorothiazide (Esidrix, Hydrodiuril), chlorothiazide (Diuril), chlorthalidone (Hygroton), indapamide (Lozol) |
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Definition
| unsubstituted sulfonamide group; have similar pharmagological & toxilogical profiles but differ in potency & duration of action; secreted by organic acid (anion) secretory system in proximal tubule; use parenteral administration only in emergency situations; inhibit Na-Cl-symporter in distal convoluted tubule promoting NaCl excretion & water diuresis; diuretic action is independent of pt acid-base balance; |
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Term
| Therapeutic Uses of Thiazide & Thiazide-like Diuretics |
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Definition
| mild-moderate edema of heart failure; HPN alone or in combination; useful in preventing Ca nephrolithiasis & osteoporosis by decreasing excretion of Ca; paradoxical effect in tx of nephrogenic diabetes insipidus - reduces urine volume up to 50% due to volume contraction leading to increased proximal tubular reabsorption |
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Term
| Toxicities, ADRs, & C/I's of Thiazide Diuretics |
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Definition
| hypokalemia; metabolic acidosis; exacerbation of Gout; sulfonamide hypersensitivity - SJS; hyperglycemia; increases LDL-C, T-C, & T-TG except indapamide; |
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Term
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Definition
| only thiazide diuretic that DOES NOT increase LDL-C, T-C, and T-TG; useful in pts with high LDL-C |
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Term
| K-sparing Diuretics (ENaC inhibitors) - triamterene (Dyrenium), amiloride (Midamor) |
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Definition
| inhibitors of renal Na channels (ENaCs); secreted in proximal tubule by organic base (cation) secretory system; oral; blocks luminal Na channels (ENaCs) in principal cells of late distal tubule & collecting duct; prevents K secretion by decreasing K entering cell for secretion & decreased electronegativity of lumen; decreases H secretion by intercalated cell; not powerful diuretics |
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Term
| Therapeutic Uses for K sparing diuretics (ENaC inhibitors) - triamterene (Dyrenium), amiloride (Midamor) |
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Definition
| limited diuretic capacity; mostly used in combination with other diuretics to treat edema & HPN; counterbalances hypokalemia caused by thiazide & loop diuretics; |
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Term
| K-sparing Diuretics (Aldosterone antagonists) - spironolactone (Aldactone), eplerenone (Inspra), drospirenone (Yasmin) |
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Definition
| synthetic steroids metabolised by liver into active metabolite; maximal diuretic effect seen on 3rd day of therapy; antagonist at mineralcorticoid receptors (aldosterone receptors); bind to receptor, preventing aldosterone-induced gene transcription; clinical effect dependent on levels of endogenous aldosterone; inhibits effects of aldosterone causing decrease in luminal Na conductance, decreasing basolateral Na/K ATPase activity, & decreasing secretion of K & H; |
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Term
| Therapeutic Uses of K-sparing Diuretics (Aldosterone Antagonists) - spiranolactone (Aldactone), eplerenone (Inspra), drospirenone (Yasmin) |
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Definition
| usually adminstered with a loop diuretic or thiazide diuretic to treat edema (CHF, hepatic cirrhosis) & HPN; prevents hpokalemia; treats hyperaldosteronism |
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Term
| Toxicities, ADRs, & C/I's of K-sparing Diuretics (Aldosterone Antagonists) |
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Definition
| life-threatening hyperkalemia; do NOT use with another K-sparing diuretic; antiandrogen effects - gynecomastia, decreased libido, impotence, menstrual irregularities; C/I in pts using ACEIs |
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Term
| Anti-diuretic drug - desmopressin acetate (DDAVP) |
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Definition
| similar in structure to vasopressin; increases water reabsorption by collecting ducts in kidney; greater antidiuretic effect than vasopressin but has greatly reduced CV vasopressor activity than vasopressin; Therapeutic Uses: nocturnal enuresis, central diabetes insipidus; ADRs: water intoxication |
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