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?

[Mollypita]

I had vague memories of hearing this too, that 1000 ml out was the max. But then last year we had a patient who had severe retention, and a urologist finally managed to catheterize him. He drained over 6000 ml!!! I was truly amazed. So, I think it's one of those things that many of us have heard, but which is not followed so much in practice.

[meanmaryjean, DNP, RN]

I had vague memories of hearing this too, that 1000 ml out was the max. But then last year we had a patient who had severe retention, and a urologist finally managed to catheterize him. He drained over 6000 ml!!! I was truly amazed. So, I think it's one of those things that many of us have heard, but which is not followed so much in practice.

Whiskey. Tango. Foxtrot!

[nurseprnRN, BSN, RN]

This is an old wives' tale from I can't think when. I can't believe we still hear about this. But the, "We were taught..." and "I always heard that ..." never seem to have heard any evidence-based basis for the practice when they learned it. I can find exactly no experimental or evidence-based support for the idea that draining a big bladder is gonna invite vascular disaster.

Here's a paper from 1989 entitled "The Mythical Danger of Rapid Urinary Drainage." (LOVE the title!) Nice study, with more references at the end.

http://epublications.marquette.edu/cgi/viewcontent.cgi?article=1068&context=nursing_fac

Here's a link to another AN thread about this. Seems lots of people have drained lots of liters with little ill effect. I know anecdote is not the singular of data, but on the other hand, a huge nuber of anecdotes aren't entirely meaningless. See study, above.

https://allnurses.com/general-nursing-discussion/whats-most-urine-686914.html

[RoamFreeRN]

And what if it's not a straight cath but upon insertion of an indwelling foley? Would you still clamp after x amt? (I never have)

[BSN-to-MSN, ADN, BSN, RN]

clamp straight cath or foley at 750ml.

[KelRN215, BSN, RN]

I can pee 1000mls at a time no problem. Usually in the morning. Never hurt me to pee that much and I never felt close to fainting. In fact I consider myself very normal and that is what my bladder can hold. Never went into shock having my usual morning pee either.

I agree. I can easily pee that much and more. When you pee, you don't stop after emptying your bladder halfway and say "that was 500 mL, can't go anymore." No, you empty your bladder. The urine is just sitting in the bladder, it's not serving any purpose as far as fluid balance goes.

[jcbhappy]

Well.. Maybe the shiver from a good 'ol fashioned "pee chill" is the basis for some of the myth. I have seen a BP high and low after 1000 plus of urine and BM small to moderate without a vagal response (specifically related to SBO).... The body is truly amazing.

[wooh, BSN, RN]

I agree. I can easily pee that much and more. When you pee, you don't stop after emptying your bladder halfway and say "that was 500 mL, can't go anymore." No, you empty your bladder. The urine is just sitting in the bladder, it's not serving any purpose as far as fluid balance goes.

But obviously you should. I heard that's how Elvis died. :)

[jadelpn, LPN, EMT-B]

But obviously you should. I heard that's how Elvis died. :)

:roflmao:That is an old wives tale, I think.....

I remember it was something about too much fluid loss at one time, upsetting the fluid balance....

Some facilities have policies regarding this. Others it is a practice issue. Much like if you drain acities or some other excess fluid--there is a limit.Can it make a patient hypokalemic to drain more than 1 liter of fluid from the bladder? Depends on the patient. And if not a policy, a practice.

But with all of the guidelines regarding catheters and the need to get them out at the earliest possible scenario--seems like the practice could be in direct conflict with a policy.

[wooh, BSN, RN]

I've never understood the theory about it upsetting fluid balance. Now, being honest, fluid balance and urinary system has never been my strong points in A&P, but once it's in the bladder, isn't it already outside of the whole system of fluid balance? Please (anyone!) correct me if I'm wrong on that. The whole abdominal aorta theory:

The theory is that because the bladder is distended the abdominal aorta cannot expand that much. If the is a sudden removal of a large amount of fluid from the bladder the abdominal aorta can expand and the resistance is reduced causing a drop in BP.

Now that almost has me convinced it's a real thing to be worried about, as it sounds like a much more plausible explanation. Although even with that, I still believe it's more Old Nurses' Tale than real thing to be worried about.

[KelRN215, BSN, RN]

:roflmao:That is an old wives tale, I think.....

I remember it was something about too much fluid loss at one time, upsetting the fluid balance....

Some facilities have policies regarding this. Others it is a practice issue. Much like if you drain acities or some other excess fluid--there is a limit.Can it make a patient hypokalemic to drain more than 1 liter of fluid from the bladder? Depends on the patient. And if not a policy, a practice.

But with all of the guidelines regarding catheters and the need to get them out at the earliest possible scenario--seems like the practice could be in direct conflict with a policy.

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.

[Anna Flaxis, BSN, RN]

Since the abdominal aorta bifurcates at L4 and the urinary bladder sits right above the symphisys pubis, how plausible is compression of the abdominal aorta?