Measuring I & O with CBI

emoening · Mar 8, 2010

Our CBI bags are 3,000cc. We have a flow sheet that had columns for: bag#, amt. in (which is always 3,000), total amt. out, and urine output. So let's say bag #1 has just finished going in, and you empty 3,800 out of the foley bag. The Urine would be 800, because you know the CBI bag was 3,000cc, so anything after 3,000 out is urine. Let's say you're running at a brisk rate and you have to empty before a full bag is in. You just keep a running tally of how much you empty, and once a full bag has gone in, you subtract 3,000 from the total amt. you've emptied. So in essense, your actual urine is always: what you empty from foley minus 3,000. Let's say a full bag has gone in, but you only empty 2,800. Then the pt. didn't put any urine out for that bag, and you're in the negative (-200).

As far as it being "continuous" and not being able to stop it to empty, there is no harm in clamping momentarily to empty the foley and then unclamping..that should take all of about 1 min. and then it's right back on.

I hope that would not too confusing to explain..it makes sense in my head lol!

pennyaline · Mar 8, 2010

Can someone explain in an easy way how to measure I &O on a CBI? How do you know how much is the pt urine and how much is the irrigation? If it's continuous, you are not able to pause to count I&O for that particular bag before setting up the next one. It seems like you are randomly measuring output as the collection bag gets full, and randomly setting up irrigation. How do you keep it all straight?
Thanks!
- a nursing student :)

It's not random. There is a total number of cc's of irrigation run during the tally period. Once all of the output for that same period is measured totaled up, the number of cc's of irrigation solution is subtracted from it. What's left is the urinary output.

PostOpPrincess, BSN, RN · Mar 8, 2010

We don't measure CBI.

It's not practical nor efficient.

fungez · Mar 8, 2010

Yeah, unless they write an order for I and O I don't worry about it. Those bags might say 3 liters but who knows how accurate they are.

Now, when I worked oncology and we were giving high dose cytoxan, the output was important. Some genius figured out how to rig the CBI tubing to the IV pump so we would know how much was really going in.

janette87 · Mar 8, 2010

We dont measure output on CBI either, I have never seen an order for I&O for a pt with CBI. I can only imagine what a pain that would be, dumping the bucket and hanging new bags is time consuming enough! Plus I wonder how accurate it would really be.. even for an 1000cc IV bag running on a pump there is still a little left over in the bag after 1000 has run through.

cherrybreeze, ADN, RN · Mar 8, 2010

I will respectfully disagree that it's not necessary to measure output with a CBI...the majority of our CBI's, when we do see them, are on post op patients (we don't see them often, though, with the advancements in TURPs and prostatectomies....when I started, we saw them on everyone!). I think you DO need to know if all that's coming out is what you're putting in! People have issues with low UOP post op for a variety of reasons, from benign to serious, and it's an easy yet important measure to watch.

It's not hard to do, etiher. If you're running at a fast rate, yea, you're going to be changing bags/emptying foley's pretty often. Using a 4000ml drainage bag helps, and put a couple of graduates in the room, so you're not making as many trips to the bathroom to dump/refill. When you empty a bag of NS, write down the amount from that bag. At the end of the shift, you mark the bag where you're leaving off (say, if there's 1000 left) and count the 2000 in. Empty the foley bag at that time. Write on the bag itself, by your line, how much you're estimating to be left (someone's 1000 might be someone else's 1250, depending on how they look at the bag). Subtract the UOP total from the CBI in total, and you have your true UOP. We rarely have the numbers get messed up, and if the UOP is low, you'll see that trend (of course, there is a margin of error with the bags, as not ALL can be infused, but in two or three shifts you can see if your numbers are too "equal" to each other).

Hope that made sense like it does in my head. :lol2:

SweetLikeSugar · Mar 8, 2010

I work on a post-op floor and our urologists ALWAYS write "strict I&O" for their CBI patients. When they come in and look at the I&O sheets, they get pretty pissy (no pun intended!) if they think our counts are inaccurate. We usually have the CBI going pretty quickly and the foley bags fill up fast. The way our floor measures it is to use a marker and draw a line across the irrigation bag and figure out how much has infused from the 3000cc bag and subtract that from the total UOP in the foley bag. It doesn't seem to be terribly accurate, but that's what the urologists require us to do.