Why do fluid bags come full of air?

[urge]

Is there a purpose to it?

Does it make manufacturing easier?

It certainly does not help us. All it does is get the lines full of air when the bags run out.

Do you routinely take the air out?

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[nap$ter]

Is there a purpose to it?

Does it make manufacturing easier?

It certainly does not help us. All it does is get the lines full of air when the bags run out.

Do you routinely take the air out?

no, yes and yes.

i remember an m and m during residency at our children's hospital - a resident took over a case and put a bag under pressure - the manufacturer's air was pushed into the patient who coded briefly.

 

[ZzzPlz]

Don't wanna hijack the thread, but also, why is there moisture around the bag of fluid when you remove them from the outer sealed bag?

 

[Mman]

Don't wanna hijack the thread, but also, why is there moisture around the bag of fluid when you remove them from the outer sealed bag?

I throw those bags out.

 

[urge]

I throw those bags out.

I don't know the answer for sure but I assume it is due to different temperature and humidity from the manufacturing plant and the OR. It's a fluid packaging plant; the humidity must be pretty high. Probably pretty hot too. The water would condense inside at a lower temperature if the bag is intact.

I wouldn't throw them out.

 

[Mman]

I don't know the answer for sure but I assume it is due to different temperature and humidity from the manufacturing plant and the OR.

I wouldn't throw them out.

My confidence in the sterility of the fluid drops when the exterior of the bag is wet. It's well under 1% of our bags that come that way.

 

[urge]

My confidence in the sterility of the fluid drops when the exterior of the bag is wet. It's well under 1% of our bags that come that way.

Makes me wonder if that 1%, are the bags that have an intact outer bag.

 

[risnwb]

My confidence in the sterility of the fluid drops when the exterior of the bag is wet. It's well under 1% of our bags that come that way.

I'd say like 30-40% of our bags have fluid on them. I only remove the air if I'm using a high flow line or will potentially pressurize it....

 

[chocomorsel]

That's wasteful Mman. I suspect there are many things you do in the OR that aren't exactly "sterile". We all do. Glad we live in this wonderful country where money grows on trees.
It's just condensation due to temperature differences.

Only time I take the air out is when I put a pressure bag on it. Otherwise, I just suck out the air with a syringe if it's in line. The valves (I believe) keep it from going too far. Whatever the case, It rarely gets past the first port.

 

[Mad Jack]

I throw those bags out.

That's almost every bag of water or saline I ever opened at my old hospital lol. We wouldn't have any left.

 

[Mman]

That's wasteful Mman. I suspect there are many things you do in the OR that aren't exactly "sterile". We all do. Glad we live in this wonderful country where money grows on trees.
It's just condensation due to temperature differences.

How do you know it's "just condensation"? You sure it isn't a microscopic break in the bag? As for wasteful... at an average acquisition cost of $5-10 a bag, I don't think tossing 1 of every 200 is too bad. I'd rather not give contaminated IV fluids to a patient if I can help it.

 

[urge]

How do you know it's "just condensation"? You sure it isn't a microscopic break in the bag? As for wasteful... at an average acquisition cost of $5-10 a bag, I don't think tossing 1 of every 200 is too bad. I'd rather not give contaminated IV fluids to a patient if I can help it.

The fluid bag would be somewhat empty. Those things are put in boxes and carried around the US, then stored at your hospital for a few months before you get them.

There would be more fluid between bags also. The outer bag has to be intact, otherwise it evaporates.

Plus, it would leak if you pressurize it.


I think you are throwing away your better bags. The ones with an intact outer bag.

Anyway, why do fluid bags even come inside a bag? Can't they just have a wrapper on the injection port to keep it clean?

 

[Mman]

I think you are throwing away your better bags. The ones with an intact outer bag.

I'd submit that if 99.5% of our bags don't have fluid that the 0.5% that do have fluid are likely not "the better bags".

 

[RxBoy]

Ive never bothered to deair an IV bag. But Im curious, when there is no air, how do you fix the drip chamber when its completely full of fluid after getting backed up. With air in the bag I put the IV bag upside down, squeeze on the chamber and little air gets sucked in so you can see the IV dripping again.

 

[pgg]

Air inside the IV bag itself could just be air coming out of solution in the time the bags just sit there. I wouldn't expect them to degas it. I remember taking chemistry in college and for some experiments we could use the deionized water out of the special taps, but for some we had to use deionized and degassed water from a tank. But I have no idea how much dissolved air would normally be in 1L of water after the manufacturing process.

Water outside the IV bag but inside the outer wrapper is surely just condensed humidity. I'd say a majority of our IV bags have some condensation inside the outer wrapper.

 

[CardiacIntensivist]

Ive never bothered to deair an IV bag. But Im curious, when there is no air, how do you fix the drip chamber when its completely full of fluid after getting backed up. With air in the bag I put the IV bag upside down, squeeze on the chamber and little air gets sucked in so you can see the IV dripping again.

Close off clamp. Disconnect bag from chamber. Squeeze drip chamber to "air" it. De-air fluid bag. Reconnect.

 

[ranvier]

The printed info on our baxter bags explicitly state to discard if moisture found when outer wrap removed.

 

[Mman]

The printed info on our baxter bags explicitly state to discard if moisture found when outer wrap removed.

yep

I suppose it can vary from manufacturer to manufacturer, though.

 

[scudrunner]

I'd venture to say that nearly 100% of our LR bags have significant condensation on them, and all have air in them. I remove it most of the time. We have an attending who practiced in Canada and said that the fluid bags there had no air in them. Weird.

 

[musli]

Weird. Before I read to the end of this thread, I thought "that's interesting" and called Baxter. Their tech people told me that the IV bag plastic leaches fluid over time, and that this isn't a problem and doesn't compromise sterility. Apparently they get this question enough that they have a pre-printed letter about it.

Ranvier, are your bags made with "Viaflex" plastic? Or something else?

 

[ranvier]

I double checked this today.
I was wrong.
They are braun bags. The insert states to squeeze and discard for leaks....not condensation.
I have never found either one....or an ett cuff with a hole (that wasnt placed ie difficult dlt).

 

[Ronin2258]

Is there a purpose to it?

Does it make manufacturing easier?

It certainly does not help us. All it does is get the lines full of air when the bags run out.

Do you routinely take the air out?

The air is there to allow the bag to expand and contract with temperature variation. A bag completely full of fluid only would be tight (the company would save the money for the extra plastic to keep cost down.) It would burst if it got too warm or froze (remember, water expands when it freezes.) Air would contract as things get colder, allowing the water in the fluid to expand if the bag freezes. The air would be compressed if the bag gets warmer.

I also purge the air out of the bag for an a-line setup, but had to leave some air in the drip chamber. One attending would give a verbal dress down if you didn't.

Don't wanna hijack the thread, but also, why is there moisture around the bag of fluid when you remove them from the outer sealed bag?

I was made to understand when I was a tech that the fluid was there to allow you to pull the bag out of the outer dust cover easier. the plastic of the outer wrap and the plastic of the fluid bag tend to stick together. The fluid made things easier to pull the bags out in a rush.

I never heard of the Baxter bags leaching out fluid over time, but I can see that happening.

 

[musli]

The air is there to allow the bag to expand and contract with temperature variation.

That does not seem logical; gas expands and contracts a great deal with temperature variation (PV=nRT). Liquid water hardly changes its volume at all, by comparison.

If freezing were a real possibility, and if the container were rigid, I could see the logic. But there's nowhere near enough air in the bags to account for a 1/9 increase in volume as the solution froze. And in any case, the package insert in LR always says "protect from freezing," so I doubt that the Baxter guys would plan their design around an off-label use.

Best wishes.

 

[propadope]

I think I know the answer to this. First post guys so go easy. Don't you need a fluid-gas interface to determine how much fluid is in the bag?

Jonathan

 

[chfo]

I think I know the answer to this. First post guys so go easy. Don't you need a fluid-gas interface to determine how much fluid is in the bag?

Jonathan

exactly

 

[jacksonrees]

Yes to some of the above, and bosh folklore for others. Just as surgical gloves are somewhat porous, and double gloving helps increase protection from virus, so, too, does a minor amount of transudation through the plastic bag occur, but not so much as to alter what is provided. Incidentally, there is usually a ~/>5% surplus over nominal volume for priming lines, etc. (By the way, when you infuse the entire replace bag including its overfill, do you "count" that overfill volume, or simply assume it? In overload prone, or dialysis dependent patients, large uncounted volumes might confuse the issue.

The manufacturer's instructions or website are the best source upon what to expect. Small amounts of damp within the protective over-wrapper for shipping (which should not be removed in advance of need) may be ignored provided there is no true leak in the bag.
Other plastics, such as the polyolefin bottles, do not have the same degree of permeability.

In routine use, not pressurized lines, an air-fluid meniscus is important to determine volume infused without a pump-controller.

The extra bag space is also useful for admixture of additives (NaHCO3, Vitamins, Drugs, etc.) by the pharmacy, but the true volume should be calculated for concentration or Intake and Output measurements.

Sincerely,

Jacksonrees