Supplemental O2

I have been on xPAP for seven months. I was originally diagnosed with moderate OSA (no centrals) with an AHI=23. I was titrated to a pressure of 10 cmh2o and was also perscribed supplemental oxygen at the rate of 2L/minute. I currently use a REMstar Auto and Mirage Activa (alternating with a Swift). My REMstar operates in Auto mode set to 9.5-12 cmh2o, and runs right around 10 throughout the night (NEVER above 10.. I enjoy AHIs<0.2 consistently. My supplemental O2 is delivered by an Invacare Platinum 5 oxygen concentrator.

Here's my question: The supplemental oxygen is delivered to my "circuit" through a simple double male fitting with a nipple and a short length of oxygen tubing attached to it, between the end of the CPAP delivery hose and the short hose of the Activa (or Swift). I run a 25 foot length of hose from the Platinum 5 (which is in another room for noise reasons) to the fitting on the short hose coming from the nipple on the fitting. This was the set-up delivered by my DME at my initial set-up 7 months ago, and it has NEVER been inspected or calibrated since. The flow-rate meter on the Platinum is set to 2 liters.

My question is, given this set-up, is it delivering ANY oxygen to my mask? I felt the rush of pressurized CPAP air coming out of that nipple the other night, before I connected the hose from the Platinum. There was a RUSH of air coming out of the nipple. In contrast, there was a flow of relatively low pressure oxygen coming from the hose connected to the Platinum. I wonder how that oxygen isn't getting blown BACK to the concentrator simply by the pressure of the CPAP air.

I'd very much appreciate the comments of any RRTs who might happen to review this.

Many thanks!!

Chuck

I too was on O2, 2 lpm, in the past. As long as the flow meter on the concentrator is at the 2 lpm indicator mark when you are using the XPAP and mask, it is putting 2 lpm of O2 into the flow. It needs to be adjusted to 2 lpm flow with the mask working.

Heres the big problem, which the Dr's can't see and don't address. In the daytime, you are using O2 at 2 lpm, breathing it directly.

At night using the same rate of O2, 2 lpm into xpap stream, you are getting a watered down dose of O2, because the 2 lpm of O2 in mixed into a 30+ lpm of XPAP flow, making the O2 level increase in the XPAP stream, much lower than the enrichment of the daytime level.

I confronted my Dr., and got that Famous Deer In The Headlight Look, ( I think they have to take a special class for it.) I don't think they teach Common Sense or Physical Science, in Med School.

So I cranked my concentrator up to 4 lpm, when I used XPAP with it. I figure the rate would be twice what the Dr. ordered, and maybe 1/6 the level of my daytime treatment.

I was just operated on a couple of weeks age, and they used XPAP during the operation, They wanted to add O2, but had no clue as to how much, I told them to set it at 4 lpm, and they did, and life went on. Jim

What I should have told them was, how much Novacaine to use, that's where the trouble came in.

My husband and I both are on supplemental O2 at night. We have a New Life Dual 6 which is not made any more. We have plastic pieces with a fitting for the O2 line to attach from the machine to the CPAP hose. The O2 then runs through the hose to the mask.

Forgot to ask, does your O2 in-line adapter, have a check ball and vent built in it, if it doesn't, the XPAP unit needs to be turned on before the concentrator is hooked to the XPAP, to keep the O2 from going into the XPAP. (Fire Hazard)

If yours does have the check ball the XPAP won't autostart. The flow can't get back to start the XPAP. Jim

GoofyUT, Why do you need supplemental O2? What were your blood oxygen levels with 10 cm H2O and no supplemental O2? At 2 LPM O2 and 10 cm H20 at home, what are your blood O2 levels? What do your desaturations look like, i.e., duration, minimum O2 and number per hour below 88%?

The only way to know for sure what the oxygen concentrator should be set at is to do an overnight pulse ox study with it hooked up and adjust accordingly.

Your question is a good one though. I'll do a little research and see what I can come up with regarding the back pressure.

Chuck,

As a practical matter of determining the effectiveness of your own treatment, wouldn't your nighttime SpO2 tell you everything you need to know? I seem to recall that you own an oximeter already, so this should be easy for you.

As to the matter of prescribing oxygen treatment on xPAP, it looks like you've stumbled into another treatment area which reveals yet again the appalling lack of analytical thinking skills of most of those who "practice" the art of medicine.

It's good that you're taking charge of your own health care, Chuck. You deserve the best, and there's no one else quite so interested in your own health as you are.

Regards,
Bill

I too, got a little confused as to how O2 is added to PAP and wrote several mfg as well as a couple of forums and NEVER got an acceptable answer.

Some claimed the O2 is added with a Venturi or Bernoulli's priciple.
This is imposible since the O2 is connecto toe output manifold and cannot "suck" the O2 in.

Inomed answered that O2 concentrator cannot be used with PAP. They make the machines.

If a PAP has an output of 12 cm H2O, then any connectio to the output will alter the pressure delivered.
If a setting of 2L/min is delivered to the connection, then 100 pct of ths inspired must be provided by the concentrator.
for ANY of the O2 to be delivered, it must negate the inflow from the CPAP and the relative pct of each- PAP and concentrator- MUST affect the delivered pressure.

I do no know how it is possible for a constant delivered pressure to be delivered if an O2 connection is introduced.

I am still waiting on an explanation of this
tom

Bill-

In the past I've tangled with you regarding your assertions of the "Big Lie" regarding the position that the medical community takes that they, and they alone, possess the knowledge and skills to treat us, the patients.

Sadly, I've come to understand that you were right all along. My experiences with the sleep medicine community has been abyssmal! My latest series of questions regarding my therapy with supplemenmtal oxygen illustrates this.

I was started on supplemental 02 ( at night only) immediately following my heart attack seven months ago, while in the hospital recovering from my MI. When I was discharged, my pulmonologist ordered xPAP treatment and my DME fillled the order with equipment which was delivered shortly after I returned home, with about 10 minutes of patient education and instruction. They've NEVER been back since, to check, calibrate or resupply the equipment. They've (doc and DME) NEVER called to inquire whether I was even using it, or how I was doing.

I have wondered about my actual need for the night-time supplemental o2, especially since I've lost a considerable amount of weight, and I have engaged in an aggressive and consistent physical exercise program. As you know, I purchased a Nellcor N-395 recording pulse/ox, and I've been delighted to see that, according to the readings of the N-395, my nightime sats have risen to 95-98% with a couple of excursions down to 87%, with sats < 90% lasting less than 2 minutes total.

So, I asked my sleep doc to reevaluate my need for supplemental 02 at night. He appropriately ordered an overnight pulse/ox and I was issued a shop-worn Nonin RM2, which I wore one night. I did wake up in the night once at about 2AM, and noticed that the LED had gone out on the RM2 (it was set to record from 11-7am). When I dropped the RM2 back with my sleep doc, I told him that they LED had been out, but he said not to worry about that.

Predictably, he NEVER called back with results, but I did call him a few days later, and he reported that he hadn't read my study. I told him that I was due to travel and I wanted the results immediately. He then read the study (such as it was), and called to say that I was having frequent excursions into the 70s and instructed me to stay on the supplemental 02. I was SHOCKED! My N-395 reported no such desats! I asked, and he admitted that the results of the overnight RM2 study could be artifacts, but continued his instructions. He didn't offer to repeat the study with a pulse/ox that they knew worked correctly, and he relied upon the results from a pulse/ox that I knew was malfunctioing from my own observations when I awakened in the night.

I'm a licensed health care professional myself, and I was a medical school professor for many years. I believe strongly in good patient care, and I tried to teach this consistently to my students. So, I ruffled against your assaults on the profession. But, given the care I've received from my pulmonologist and DME, I can clearly see now, that good, competent care should NOT be assumed in ANY case! And that behooves us all to protect ourselves by becoming as knowledgeable as we possibly can about the disorders for which we are being treated.

Fortunately, my internist fulfills every standard I could have about what a good doctor should be. I've shared my concerns with her, and though she agrees, she's forlorn that sleep medicine is almost monopolized by the one clinic owned by my insurance carrier, which is a HUGE health care consortium here in the intermountain west. I'm obliged to use this clinic, and apparently, I'm out of luck.

So Bill, my hat's off to you and with all due humility, I'll admit that you were right, and I was wrong. Now, what's a boy to do?

Chuck

[quote="tomjax"]I too, got a little confused as to how O2 is added to PAP and wrote several mfg as well as a couple of forums and NEVER got an acceptable answer.

Some claimed the O2 is added with a Venturi or Bernoulli's priciple.
This is imposible since the O2 is connecto toe output manifold and cannot "suck" the O2 in.

Inomed answered that O2 concentrator cannot be used with PAP. They make the machines.

If a PAP has an output of 12 cm H2O, then any connectio to the output will alter the pressure delivered.
If a setting of 2L/min is delivered to the connection, then 100 pct of ths inspired must be provided by the concentrator.
for ANY of the O2 to be delivered, it must negate the inflow from the CPAP and the relative pct of each- PAP and concentrator- MUST affect the delivered pressure.

I do no know how it is possible for a constant delivered pressure to be delivered if an O2 connection is introduced.

I am still waiting on an explanation of this
tom

If
rant > necessary
delete rant
end-if.

GoofyUT wrote:Now, what's a boy to do?

Good question.

Hmmm, let's see....



Since you have a good internist....

GoofyUT wrote:Fortunately, my internist fulfills every standard I could have about what a good doctor should be.

Why not ask your internist to order another overnight recording pulse oxi test. Using your cpap machine without O2.

Maybe this time the DME will send a pulse oxi that works right all night.

GoofyUT wrote: Now, what's a boy to do?

Chuck

I know the answer to that one too, Chuck - just keep doing what you're doing. . . . until you get the issues which concern you resolved.

The objective after all is good treatment and, like I said, you are in the best position of anyone to judge what's good for you.

GoofyUT wrote:I'd have thought that the medical profession would have thought out an answer to this simple matter of physics and fluid dynamics.

It's the appalling lack of critical analytic thinking skills among the medical profession, Chuck. I have read the results of many medical studies which fail to differentiate between correlation and causation, for example, an important distinction which is frequently ignored, often in order to jump to a desired conclusion which benefits the income stream of some health care group. I can just imagine that this obliviousness to important details drives serious statisticians absolutely nuts. The failure to distinguish between correlation and causation would be sufficient grounds, by itself, to reject many, many, many "esteemed" medical studies if the profession had sufficient safeguards, or checks and balances, in place, which they clearly do not.

[rant ON] . . . Rant deleted . . . [/rant OFF]

Regards,
Bill (mercifully cutting short the desire to diatribe)

It is my humble opinion that this thread highlights some of the major problems with healthcare here in the good, ole USA.

What is REALLY amazing is that we are the fortunate ones who understand enough of what is happening to us to question, research, seek other opinions, etc.

What about the ones most in need who cannot advocate for themselves?

Chuck, can your PCP recommend specialists in OTHER areas of the state who appear to be at least REASONABLY competent? Travelling may not be such a bad idea, under the circumstances. Or, can your DME provider use an out of state doctor's scrips and can the out of state doc order your testing? If you travel out of state, seeing a competent doc for an extra day may be worthwhile.

birdshell wrote:What is REALLY amazing is that we are the fortunate ones who understand enough of what is happening to us to question, research, seek other opinions, etc.

I hope that I'm wrong, birdshell, but it's my belief that cpaptalk is unique in having fostered this environment. I have looked for something similar in regards to a couple of other medical maladies I have, GERD and retinal detachment. I found forums but nothing that approaches cpaptalk in information sharing seems to be out there. Perhaps cpaptalk is the first to reach critical mass.

birdshell wrote:What about the ones most in need who cannot advocate for themselves?

Don't forget that category includes most of us. Most of us couldn't effectively advocate for ourselves before finding cpaptalk either.

birdshell wrote:If you travel out of state, seeing a competent doc for an extra day may be worthwhile.

I'll vouch for that! One of the best moves I made regarding my eye problems was to see a renowned retinal surgeon in Memphis. He was able to, in a matter of seconds, diagnose an entirely unexpected problem, at the front of my eye, which had been my primary limitation to good vision. Seems one of the local surgeons had done a poor job of performing a YAG capsulotomy, or as he simply described it; "It was ineffectual." None of the half-dozen local eye specialists I'd seen had seen fit to mention that to me. (Kinda raises the question of whether they were protecting the local surgeon, or whether they were simply incapable of diagnosing a very simple problem.) At any rate, another YAG capsulotomy on that eye did wonders for my vision.

I'll also add that the surgeon I saw in Memphis is also a mechanical engineer who developed perhaps most of the microsurgical tools in use today by retinal surgeons (and that assessment from a local retinal surgeon). I have a suspicion that he is a rarity in the medical realm with his ability to think analytically and effectively solve problems.

Compared to the other vagaries in the medical system, seeing a renowned specialist halfway across the country is not that big a deal. (I worked the Memphis visit in with vacation travel.) What's even more amazing is that such specialists truly want to see challenging patients. I've inquired twice now of eye specialists in quite different geographical locations, and the folks I talked with were very accommodating in regards to making an appointment. I suspect renowned specialists in other medical disciplines would be similarly accommodating.

Regards,
Bill