NS for urine replacement & mannitol ?

suzanne4, RN · Jun 21, 2005

Mannitol is being used to lower the ICP by pulling fluid out of the head......

You can still get dehydrated with the increase in urine output being caused by the shifting of fluids.

How old is the patient and any other issues going on? 70 ml is not much in the way if fluids per hour.

HyperRNRachel · Jun 21, 2005

19 y/o, tested positive for cocaine, ETOH, and THC. Played Russian Roulette and was (somehow) shot behind the right ear, with bullet lodging in left front lobe. Other than the gunshot injury there is no other medical problems. He is clinically paralyzed with VECURENIUM and sedated with ATIVAN. TPN is running at 50 ml/hour. In all 180ml of fluid an hour but his I&Os are postive 300 to 350 ml/hr but no visual edema, clear lung sounds. The mannitorl infusion was reduced by half at the end of my shift.

Any ideas?????

begalli · Jun 21, 2005

Mannitol is an osmotic diuretic and in addition to lowering ICP it can also be used in the treatment of oliguria and as prophylaxis of acute renal failure. Mannitol can obscure the signs of inadequate hydration and so I would assume (we don't use it a lot in CVICU) the patient is diuresing because of the mannitol and is otherwise healthy (esp cardiac wise), so they need to replace the fluids taken off by the drug to avoid draining the patient dry leading to all kinds of other problems.

They are probably trying to keep his I&O's as equal as possible while still lowering the ICP.

He should be getting KCL as well with the NS.

gwenith, BSN, RN · Jun 21, 2005

What they are possibly doing is ensuring adequate BP. One of the worst and most unfavourable of outcomes is hypotension + head injury. It is imperative that you maintain the CPP (cerebral perfusion pressure) with an ICP that high. Doesn't sound as if this poor chap has a very good chance though. As a rule of thumb the degree of injury with GSW strongly correlates to the caliber of gun. The greater the force/velocity behind the bullet the more damage is done.

rocks · Jun 21, 2005

In a client with a GSW to the head, ICP running 29-40, getting mannitol (250cc of 20% over 15 minutes, Q6hrs), what would be the reason for an order of "urine replacement, 1cc:1cc w/NS secondary to post mannitol infusion"? The client was already getting NS at 70 cc/hr, and the "urine replacement" was running in a separate line.

I would like to know what this person's BP is running. I think the idea is to maintain adequate hydration in the body while promoting the edema. Further, mannitol increases the osmolarity of the glomular filtrates. If the 'salts' are increased in the glomular tubules, water will follow. Without replacement, hyponatremia ensues. Putting it back seems to make sense.

Hope this helps.

rocks · Jun 21, 2005

I would like to know what this person's BP is running. I think the idea is to maintain adequate hydration in the body while promoting the edema. Further, mannitol increases the osmolarity of the glomular filtrates. If the 'salts' are increased in the glomular tubules, water will follow. Without replacement, hyponatremia ensues. Putting it back seems to make sense.

Hope this helps.

HyperRNRachel · Jun 21, 2005

I would like to know what this person's BP is running. I think the idea is to maintain adequate hydration in the body while promoting the edema. Further, mannitol increases the osmolarity of the glomular filtrates. If the 'salts' are increased in the glomular tubules, water will follow. Without replacement, hyponatremia ensues. Putting it back seems to make sense.
Hope this helps.

Thanks to everyone for the information it is really needed and appreciated. His BP is running 190/110 and the map is 110-120.

rocks · Jun 23, 2005

Thanks to everyone for the information it is really needed and appreciated. His BP is running 190/110 and the map is 110-120.

My reply should have read "promoting the removal of the edema" OOOPS! I seemed to have lost part of the reply in the cyber file 13. Sorry