Step I mannitol question

[HiddenTruth]

Ok, I am a bit confused. FA says that one of its uses is in shock, and one its side effects/toxicity is pulmonary edema. Both of these seem contradictory to its MOA (osmotic diuretic). What am I missing?

 

[omarsaleh66]

Ok, I am a bit confused. FA says that one of its uses is in shock, and one its side effects/toxicity is pulmonary edema. Both of these seem contradictory to its MOA (osmotic diuretic). What am I missing?

It is used in shock cuz remmeber that in shock, you arent getting enough flow to the kindneys and one can develop prerenal azotemia and then acute renal failure so mannitol will keep the kidneys working by its osomotic diuretic properties.

Here is what I found on the other question about pulmonary edema:

Too rapid infusion of large amounts of mannitol will cause a shift of intracellular water into the extracellular compartment resulting in cellular dehydration and overexpansion of the intravascular space with hyponatremia, congestive heart failure and pulmonary edema.

 

[HiddenTruth]

It is used in shock cuz remmeber that in shock, you arent getting enough flow to the kindneys and one can develop prerenal azotemia and then acute renal failure so mannitol will keep the kidneys working by its osomotic diuretic properties..

keeping the kidneys "running" at the expense of depleting water from an existing hypovolumic pt? That's messed up! 😱

 

[Janders]

keeping the kidneys "running" at the expense of depleting water from an existing hypovolumic pt? That's messed up! 😱

I don't think we actually care much about urine production per se, we're just doing everything possible to increased blood volume (and cardiac output) and keep the kidneys from sustaining too much ischemic damage.

Remember, when you push normal saline, only 1/3 of it stays in vessels, the rest goes to cells, extracellular-non-vessel areas, etc. By putting Mannitol or something similar in the vessels, you pull water back in (or keep it from leaving). By keeping enough volume availible, you can prevent the deeper parts of the kidney from beign damaged via vasoconstriction and lack of flow. Some diuresis is good, as massive kidney failure is a bad outcome.

The possibility of Pulmonary Edema has already been very well explained...