What is considered high-flow O2?

[Chief1C]

Uhh.. I didn't say anything of the sort.. I've never seen a nasal w/ a bag.. but I have seen an Oronasal Cannula.

[JPINFV]

Ok, I found what I was talking about above. The type of cannula is called an "oxymizer." It's more geared for long term use and essentially uses a bag near the prongs to provide a higher concentration of O2 on inspiration at a lower flow level.

http://www.pulmolab.com/respiratory/oxy_co.../oxymizers.html

[Top cannula is the adult version and the bottom one is the pediatric version]

That said, there are also "high flow" [up to 15 LPM] nasal cannulas on the market.

http://www.phc-online.com/Nasal_Cannula_p/...1600hf-7-25.htm

[Just Plain Ruff]

anyone who's had a nasal cannula on knows that if the flow is increased your nares begin to flail open.

15lpm would seem that if you needed your nose cleaned out this would do it.

[Chief1C]

Random thought... It would be funny to run water through a Nas-Can, in a prank sort of way, like during training of noobs... But in the same sense, I can see where it would go wrong. Maybe water into a NRB.. when they're expecting O2. :?

[NREMT-Basic]

Correct me if Im wrong, and I frequently am, but I was taught in school that high flow was 12-15 by NRB. I know with the disaster team Im on we now have a thing called a FourTran (spelling) respirator that runs purely off the pressure of the tank so no electricity is needed in a power outage situation. You can set it up for tidal volume, resps per minute and flow. I was sure the medical officer teaching us about it said that it could go as high as 25 LPM. Any medics out there speak to this and if its possible in what cases would 25 be used.

[dahlio]

I was always taught

1-7 lpm, Nasal Cannula

8-15 lpm, Partial NRB, I don't believe we use true NRB anymore. Anything over 12 is considered High Flow O2. Supposedly we should hook the BVM up to 25lpm of O2, but I find that to be wasteful, and 15lpm keeps the reservoir pretty full. Like I said, this is what I was taught.

[Just Plain Ruff]

nasal cannulas have been used for pranks for many years. I have at least five classic pranks that I've done with them in the past.

[VentMedic]

It's all about the fIO[sub:d10cdbaed1]2[/sub:d10cdbaed1]. That's the difference between a technician and a professional.

Very true. A 2 L NC on some on who has a minute ventilation demand of 22 L/min is not getting the text book 28%. Matching the device that will deliver the FiO2 at the patient's demand requirement is the key element. There are times when a NRBM will not work on someone with that high of an inspiratory flow demand.

Key Points:

The percentage of O2 delivered by a low flow device is variable because RA is entrained.

FiO2 will vary depending on the patients RR, pattern and VT.

Increasing flow on a high flow device will not increase FiO2, only total flow

High FiO2’s (>.60) may not meet the patient’s inspiratory flow demands

To insure adequate flow with stable FiO2’s, a special made high flow device should be used or two flowmeters set up to provide at least 40 L/min total flow

Low Oxygen (FiO2) Delivery Devices

Nasal cannula

Nasal Catheters

Transtracheal Catheters

Face Tent

Face Shield

Simple Oxygen Mask

Moderate Oxygen (FiO2) Delivery Devices

Partial Rebreathing Mask

Venturi Mask

High Oxygen (FiO2) Delivery Devices

Non-Rebreathing Mask

Oxygen Hood

Low Flow systems:

NC

Nasal Catheters

Transtracheal Catheters

Simple Face Masks

Partial Rebreathing Masks

This can include the NRBM if you are running at a fixed flow and their ability to entrain air is limited. If you remove the side port flaps to entrain RA, you are more to the "high flow" category but approaching a moderate to low FiO2 category.

High flow systems :

Venturi masks

Aerosol masks

Face Tent

T-Piece (use 50 mL of reservoir tubing to maintain FiO2 with adequate flow)

Oxygen Tent

High flow aerosol systems (Misty-Ox)

The aerosol devices mentioned will be dependent on the venturi setting on the nebulizer. If the setting is to 100%, you will have less total flow thus now may be in the "low flow" category.

High Flow Nasal Cannula systems (capable of delivering 32 - 40 L/Min of humidified O2 off a blender system for a lower FiO2 at a higher flow). ex: 28% at 20 L/Min. Used for comfort and meets the MV demand. ex. of a pt: pulmonary fibrosis.

Vapotherm

Aquinox

The oxymizer is popular in the aviatioin industry and now home care. It's expensive at about $25 each. If someone wants to conserve their O2 tank they can go from 4 L/min to 2 L/min depending on the model of cannula.

The high flow cannulas by Salter pictured above have not caught on yet due to cost and in the home care environment they would be impractical due to O2 Concentrators rarely capable of putting out more than 6 L/Min. Humidification could be an issue also. The standard NC humidifiers are not meant for more than 6 L/Min. I'm sure Salter would want the agency to buy all the accessories like all of the other companies.

If all of the above doesn't work then we go to the next level of high flow:

CPAP and BiPAP (BiPAP is a trade name for Respironics - may be called many things depending on the machine)

It's all about learning the principles of operation and not memorization.

[fiznat]

Wow Vent! haha I'd say that answers the question! Nice post.

[dahlio]

Definitely, A very well detailed explanation. So if my service doesn't carry full non rebreathers, then the only way one of my patients are getting hi-flow O2 is through BVM? Interesting.