Term
| What determines the effect of a diuretic? |
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Definition
| *The nephron site at which it acts. |
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Term
| What is the MOA of Mannitol? |
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Definition
| *Osmotic diuretic that is filtered into the tubular space where it markedly increases tubular fluid osmolality resulting in impaired reabsorption of fluid causing an increased excretion of water and sodium. |
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Term
| What is the onset and half life of mannitol? |
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Definition
*10 minutes
*T 1/ is 1.2 hours |
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Term
| What is the major toxicity associated with mannitol? |
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Definition
*Increased plasma osmolality
*Mannitol is retained in ECF in a state of reduced GFR
*Causes water to move out of cells into the ECF potentially worsening HF and hyponatremia |
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Term
| When is mannitol indicated? |
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Definition
*Prophylaxis against ARF secondary to physical trauma or surgery
*reductions of cerebral edema and IOP |
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Term
| What disease states contraindicate the use of mannitol? |
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Definition
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Term
| What is the MOA of carbonic anyhydrase inhibitors such as Acetazolamide, dichlorpenamide? |
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Definition
| *Sodium reabsorbed and exchanged for K+ in distal nephron, therefor CAI causes an increase in urinary HCO3-, K+, and H20 Excretion |
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Term
| What is the MOA of loop diuretics? |
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Definition
*Blocking Na+/K+/Cl- co-transporter of the thick ascending limb of henle's loop
*this is where urine is concentrated and diluted
*Major site of Ca++ and Mg++ reabsorption
*Increase urinary H20, Na+, K+, Ca++, Mg++ excretion
*Cause dilation of venous system and renal vasodilation mediated by prostaglandins
-causes prostaglandin release |
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Term
| What is the MOA of collecting duct diuretics such as spironolactone? |
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Definition
| *Inhibits action of aldosterone by competitively binding to cytoplasmic receptor and preventing events that regulat K and Na secretion adn Na reabsorption |
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Term
| What is a lipophilic competitive inhibitor of aldosterone? |
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Definition
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