Humidify low flow oxygen?

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This subject has not been addressed here for several years; there have been several published studies showing no benefit to applying humidification to flow rates less than 5L/min on the nasal cannula; however, I notice that, at least in my institution, it is a widespread practice and indeed, many nurses are still under the assumption that at 2L/min a bubbler will help relieve a dry nose.

What is your practice and has your institution changed its policy to align with evidence-based practice?

Ali, click on the "related articles" link on the right of the abstracts for more pediatric related articles, I think you will find them useful!

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Specializes in Pulmonary, Cath Lab, Float Pool.

The only benefit to humidify low flow oxygen would be the subjective one by the patient. "It doesn't feel as dry with it on". I do not know if studies would show an increase in nosocomial infections in patients who use bubble humidifiers or not. The bubble humidifiers would be an extra cost to the hospital. If it makes a patient feel better and doesn't hurt them, I guess the only question would be is it "worth" it. I think this would be a small price to pay for someones comfort.

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Specializes in ICU-Stepdown.

I was on 4LPM during most of my stay and humidification gets MY vote -I have bad sinuses to begin with, and the dry air is murder on 'em. NATURAL air is humidified. And I can't argue against Aviators' comments either.

If I have a patient on continuous O2, even low-flow, I request a humidification unit from Respiratory.

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Specializes in PICU, surgical post-op.
Ali, click on the "related articles" link on the right of the abstracts for more pediatric related articles, I think you will find them useful!

Thanks ... will do! (I think I can actually get a code from my work to get on that whole system ... I need to look into that.)

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I was reading this discussion and wow....very interesting indeed!

I also have found....I don't know if anyone else has noticed......

humidified oxygen tends to be dispersed into a lower concentration as well due to the moisture than what it actually is set at....so some patients tend to have lower 02 readings than when on straight dry oxygen........and people have argued with me on length of 02 tubing as well affecting the readings/amount being absorbed.....I have personally seen both of these effect 02 saturation readings.

I have heard the old ...."1L is 1L" when I asked respiratory people this...and I beg to differ on it......... actuallymy daughter is on 02 as a matter of fact and if she is on humidified 02...her sats drop ......put her on dry 02 they stay up.......it's really strange...but I have noticed this occasionally on other people as well ...so I know it's not me .......has anyone else ever seen this??????? Just curious.....

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Specializes in ICU-Stepdown.

can't say I've ever seen that. I'd make sure that condensation hadn't pooled in the hose or tube to the point that it was restricting airflow, but otherwise 1L should truly be 1L -the flowmeter (little marble) should read what is actually flowing INTO the humidification unit -it doesn't read the output, only whats coming out of the wall into the tube or bottle. So if you're seeing 2L, and you aren't GETTING 2L, then check your connections because you're losing air somewhere. But if air is flowing 2lpm, then 2lpm is what you're getting. Sat drops don't make sense if you're getting the same amount of air at the end of the cannula. I'd be willing to bet that the humidifier isn't connected tighly to the O2, and possibly the air hose (cannula) isn't connected tightly to the output on the humidifier.

The ONLY way your argument should hold water (2L isn't really 2L) would be if you were measuring the output from the humidifier instead of whats going INTO it. The reasons THAT would read higher than true is becuse the humidified air would be denser than non-humidified air, and that would affect the given measurement -but since you measure the flow before the bottle, that is not the case.

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Specializes in Peds.

I know of one on 1/2 lpm via trach - humidified. The only time it's not humidified is if pt. leaves home for an appt. on portable O2. There is always a humidivent on the trach as well.

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Specializes in ICU-Stepdown.

good lord, just what good is a half a liter per minute? Is that a joke?

Good point on the portable O2. My grandfather had O2 at home -a big M tank for 'emergency' (when power failed) that had a humidifier on it, and his usual o2 generator that ran on house power which had a humidifier on it (though he never seemed to get the idea that you have to change the water in the thing, and keep it CLEAN -preferably with distilled water, and change out the unit itself. I'd have loved to have taken a culture sample from that thing.

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Specializes in Trauma,ER,CCU/OHU/Nsg Ed/Nsg Research.

My understanding is that higher humidity decreases the partial pressure of O2, so if you add humidity to the natural humidity that already exists in the nasal airway, my guess would be that this increase could decrease O2 saturation, because of the decreased partial pressure. This is just a guess- I could be wrong.

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can't say I've ever seen that. I'd make sure that condensation hadn't pooled in the hose or tube to the point that it was restricting airflow, but otherwise 1L should truly be 1L -the flowmeter (little marble) should read what is actually flowing INTO the humidification unit -it doesn't read the output, only whats coming out of the wall into the tube or bottle. So if you're seeing 2L, and you aren't GETTING 2L, then check your connections because you're losing air somewhere. But if air is flowing 2lpm, then 2lpm is what you're getting. Sat drops don't make sense if you're getting the same amount of air at the end of the cannula. I'd be willing to bet that the humidifier isn't connected tighly to the O2, and possibly the air hose (cannula) isn't connected tightly to the output on the humidifier.

The ONLY way your argument should hold water (2L isn't really 2L) would be if you were measuring the output from the humidifier instead of whats going INTO it. The reasons THAT would read higher than true is becuse the humidified air would be denser than non-humidified air, and that would affect the given measurement -but since you measure the flow before the bottle, that is not the case.

Nope, all connections were secure..we checked numerous times ...and this (on my daughter) was by trach mask, which is why it came to mind when I saw this discussion.......the other times I've seen this on patients (only a few mind you) was by nasal canula and with the really long 02 tubing..like the 25 ' tube not the short one.........

I would love to do a study on this if I go for my MSN.......or if anyone has done this already....I'd be interested in their findings.......

I just find this really odd......... Thanks for your input anyway.....this has really peaked my interest!

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My understanding is that higher humidity decreases the partial pressure of O2, so if you add humidity to the natural humidity that already exists in the nasal airway, my guess would be that this increase could decrease O2 saturation, because of the decreased partial pressure. This is just a guess- I could be wrong.

No you are probably 100% right on the $$ there! However......I have seen this via trach mask (my daughter) and also in nasal canula with long 02 tubing in other patients..........

I am going to try to see if there are any studies or anything on this...I have wondered for a long time about this actually.....

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Specializes in PICU, surgical post-op.
good lord, just what good is a half a liter per minute? Is that a joke?

Not in the pediatric world!

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