How much is too much when you catheterize

[MidnightTang]

I have been a nurse for about 7 years and I remember in nursing school hearing that when you straight cath or put in a foley you should clamp at 1000 mL and wait a while, to prevent bladder spasms. Another, more experienced, nurse was told in school that it was to prevent hypotension. Some newer nurses had never heard of either. This became a topic of discussion at the nurse's station when an attending sent a resident to find out why 1500 mL had been emptied from her patient at one time. The attending claimed to have seen a patient code in a similar sitiation, but the residents had never heard of this. I spent some time looking at hospital policy and the Potter and Perry book ans found nothing. I also came up empty on article searches. Does anyone know if this is fiction passeddown through generations of nurses or is there evidence to back it up?

[wooh, BSN, RN]

Thanks Stargazer, I was thinking the AA was a bit too high to be compressed by the bladder. But then I google image searched to refresh my recollection and saw a picture that I though, "Meh, maybe if the bladder is REALLY full." :)

[KelRN215, BSN, RN]

Thanks Stargazer, I was thinking the AA was a bit too high to be compressed by the bladder. But then I google image searched to refresh my recollection and saw a picture that I though, "Meh, maybe if the bladder is REALLY full." :)

It would have to be REALLY REALLY full:

[wooh, BSN, RN]

Are you saying I shouldn't base my practice on a random Google search? But all the families that I have come in with their Google medical degrees seem to know so much more than us nurses and physicians do! :)

[jadelpn, LPN, EMT-B]

It doesn't depend on the patient. How would draining urine from the bladder make a patient hypokalemic? Any potassium in the urine has already been filtered by the kidneys and isn't in circulation. If the patient is hypokalemic due to kidney/urinary losses, they've already lost the potassium from circulation when it's sitting in the bladder.

I was just relaying what I learned in nursing school and in clinicals. And neither matter, as in my facility, it is policy that a foley is clamped at 1000 mls, and per MD order, when it should be unclamped.

And as an aside, I am not sure of too many foley bags holding much more than a liter. So for that reason only could be the best "evidence based practice" to clamp, drain the bag, then have at it again.

[canned_bread]

I drained a patient who had 1400mL, there was no change in BP, but good Lord did she sigh afterwards!

[CrazierThanYou]

I learned in nursing school that you clamp after 1000 but I think that's crap. My hospital doesn't have a policy and I drain whatever comes out.

Clamp at 550? That's insane.

[Horseshoe, BSN, RN]

We have a policy to clamp at 550. I always thought it was fluid shift causing hypotension. But if its just anecdotal, it's pretty amusing that there are still places with policies about it. Good brain teaser for the morning meeting though.

But it's not an actual "fluid shift" if the fluid is already out of circulation and just hanging out in the bladder.

[Anna Flaxis, BSN, RN]

I think it's, as GrnTea pointed out, a myth not based on evidence.

[juniperpearl]

When I was working EMS we picked up a homeless man after the police requested us ETOH on board. He topped out a urinal in the back of my truck; easily 1400 ml. I'm not even through CNA I class yet so my Anatomy knowledge is very basic but the only reaction for him was relief lol

[Wile E Coyote, ASN, RN]

I too am in the old wives tale camp. 15 years ago I was an ER tech and would catheterize the poor saps that came in with urinary retention. Got back >1500ml numerous times and the only thing I noted was that I'd made a new best friend of the patient...some visibly melted a bit into the gurney with relief. One ED MD there also agreed that the practice of clamping had no basis in science and only served to delay patient relief.

[CodeteamB]

Policy in my region is to monitor for signs of bladder spasm, and only stop briefly if they are evident. I have never seen a bladder spasm associated with catheterization. The other day I drained 1600 from a lady, she was nearly crying in relief, and I got a high five from my manager and the physician.

[GM2RN]

I had a patient in the ED once who needed a foley. I drained 4000 ml of urine and didn't bother to clamp in between. I just used 4 urinals to empty the bag. Funny thing was that neither the patient or I had any idea he had that much urine in his bladder. He had not complaint of discomfort. The wife came and got me when the bag had almost 2000 ml in it and it looked like it would blow any second!