Loop (amboss ir UW) Flashcards
Agents?
Sulfonamides: furosemide, torsemide, bumetanide
Other: ethacrynic acid
Sulfonamides?
Sulfonamides: furosemide, torsemide, bumetanide
Other agents?
Other: ethacrynic acid
Indications of loops?
Hypertension, edema, renal failure (acute and chronic), hypercalcemia, forsed diuresis, sequential nephron blocade
For what kind of edema are used loops?
Edema:
Cardiac (acute and congestive heart failure, peripheral edema, lung edema)
Renal (nephrotic syndrome)
Hepatic (liver cirrhosis)
Forced diuresis definition?
Massive diuresis for forced renal elimination of (toxic) substances
Forced diuresis implementation?
IV administration of large amounts of fluids in combination with loop diuretics
Forced diuresis indications?
Hypercalcemic crisis, severe hyperkalemia, rhabdomyolysis, intoxication (e.g., lithium)
What is sequential nephron blockade?
A combination of low-dose diuretics with different sites of renal action.
Sequential nephron blockade results in ……
progressive increases in sodium depletion.
why used sequential nephron blockade?
Used to overcome resistance to diuretic treatment.
Inefficient diuresis despite high doses of loop diuretics is caused by either renal failure (reduced number of functioning nephrons) or increased resorption of sodium in the DCT to compensate for the loss of Na+. !!!!This second effect is seen primarily in cases of monotherapy with loop diuretics.
Method sequential nephron blockade?
Method: combination of loop diuretics and thiazides → restoration of diuretic effects
Why to loops added thiazides?
Thiazides affect the distal convoluted tubule and are able to counteract the increased reabsorption of sodium caused by loop diuretics.
Method: combination of loop diuretics and thiazides → restoration of diuretic effects
How its called?
Sequential nephron blockade
If diuresis is still ineffective after sequential nephron blockade?
If diuresis continues to be insufficient, exogenous depletion of volume (typically via hemofiltration) should be considered.
What precautions show be considered in FORCED DIURESIS?
Because of the increased risk of hypokalemia and hypovolemia during forced diuresis, rigorous monitoring is necessary.
Hypokalemia and/or hypomagnesemia can lead to ……………
Hypokalemia and/or hypomagnesemia can lead to life-threatening arrhythmias
Side effects of loops? 4
Metabolic imbalances
Ototoxicity
Dehydration/hypovolemia
Sulfonamide hypersensitivity
Mechanism of action of loops? location and cotransporter?
Blockage of Na+-K+-2Cl-cotransporter in the thick ascending loop of Henle
what does cotransporter that is blocked by loops?
Cotransporters normally reabsorb Na+, K+, and Cl-.
between what structures diminish concentration gradient when loops used?
Diminishing concentration gradient between the (usually hypertonic) renal medulla and the cortex → concentration of urine is no longer possible → increased diuresis
Apart Na, K and Cl, what other electrolites also are excreted?
Decreased reabsorption of Ca2+ and Mg2+