04-14-2016, 06:11 PM
(This post was last modified: 04-15-2016, 10:24 AM by PoolQ.)
Have a great day.
04-15-2016, 03:57 AM
(This post was last modified: 04-15-2016, 05:26 AM by Asjb.)
(04-14-2016, 05:43 PM)palerider Wrote: you must have missed the link sourcing the comment from NIH.GOV.
and, no, a cpap does not blow *anything* into the lungs. you have to use normal respiration to do that.
simply put, a ventilator is a device that *breaths for you* when you are unable to do so.
a cpap, or plain bilevel, DO NOT DO THAT.
cpaps and bilevels DO NOT TREAT central apnea, NIV machines do.
I think this could be a really useful discussion but perhaps only if you, Palerider, could please try to moderate your wording sometimes so that you may then come across as less 'definately correct' about everything and less 'angry' (all those capital letters, which I understand mean 'shouting' on web forums). For me Apnea Board has always been a beacon of calm and friendly excellence - the Moderators here clearly do a great job (thank you) at preventing trolling. Lets keep it that way.
Back to the substance of the discussion - my opinion, for what it's worth, is that this debate is mostly semantics, and history. The history: I would hazard a guess that my ASV machine is as sophisticated as the 'ventilators' used for critically ill patients in hospital not even 20 years ago. And the machines I remember were about the size of a small wardrobe! But now us (often fit and healthy) people can have the same functionality on our bedside table.
Now the semantics. If one looks at some random (assorted dictionary) definitions of 'ventilation' we find:
'The supply of air to the lungs, especially by artificial means'
'In respiratory physiology, the process of exchange of air between the lungs and the ambient air'
'A machine that mechanically assists a patient in the exchange of oxygen and carbon dioxide'
'A ventilator is a machine that supports breathing. Ventilators get oxygen into the lungs and help people breathe easier'.
So, if one bases the concept on definitions, I would say that all forms of PAP are actually 'ventilators' - i.e. they support 'ventilation'.
The semantic problem then seems to be - what do doctors and lay people think of as a 'ventilator'. I have tried this out on some friends this morning and all the mental pictures described were grim i.e. the serious news in Intensive Care "I'm afraid he needs to be put on a ventilator". When I then said " so what do you think about my little machine?" (none of them know the difference between CPAP and ASV) - "Is that a ventilator?" all the answers were along the lines of "No of course it isn't. Well, actually ….... perhaps it is? You say it opens your airway blockage? and it improves your blood oxygen levels? OK then, it improves 'ventilation', so it's a 'ventilator' "
Perhaps it could be useful instead to think of 'ventilators' as:
1. First of all, 'invasive' or 'non-invasive'. Invasive is via a tube in the airway (placed through the mouth or through an external incision in the neck - a tracheotomy), non-invasive is via a mask
2. Any machine that improves 'ventilation'. I would put all versions in this category - from the most basic CPAP machine to the highly sophisticated modern equivalent of an Iron Lung.
3. And within category 2, those machines that will *also* actually 'breathe' for people who have lost the ability to breathe on their own. Which is either:
- for people with certain sleep apnoea syndromes (usually with a noticeable frequency of central apnoeas) who only need occasional support, a reminder if you like, to breathe. Bilevel PAPs with ST, and ASV machines, can do this.
- for people with a variety of different serious medical conditions e.g. paralysis of the respiratory muscles, who need this support most of the time, even for every breath, on a temporary (usually in hospital) or life-long (often used at home) basis.
Comments (but only non-shouty ones please!) are very welcome.
My current pressures: Auto-ASV. EPAP 12-14. PS 3-10
04-15-2016, 09:35 AM
(This post was last modified: 04-15-2016, 09:37 AM by FrankNichols.)
I appreciate your comment, sadly it seems that there is a growing trend to try to come up with black and white definitions for things. I have always believed that communications was about communicating -
the language is a tool, and definitions can change over time. Many people feel the need to demand that definitions do not change, and that accurate communications can only be achieved when one is very careful to use the "correct" definition and context for all words. Sadly this fails miserably as soon as the context changes - for example, "I feel like a hot dog" has many different meanings depending no the context, from surfer, to being hungry, to being a show off, etc...
In France they actually go so far as to have a "language police" which has the final say on the appropriate definitions of words, and new words may not be officially added to the language without their approval... not a good ting in my opinion, but they certainly can do that if they want.
Personally I always enjoyed the humor of James Stewart who took great pleasure in mangling sentences and using a similar word in place the the correct word to great humous effect.
But, with all that said, some always demand technical accuracy.
I think that your choice to say if it improves ability to ventilate (improves ventilation) it is a ventilator, and by definition reducing apneas improves ventilation.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Interesting that this whole thing started because I did not understand, or really think about, one single line from the Resmed website (in my first post). I personally thought that "of course" CPAP machines are not ventilators as they do not breathe for you.
I have also heard, but not actually done the math myself that CPAP machines do not have enough pressure to breathe for you or even clear an apnea that has already happened. The CPAP machines try and prevent apneas from happening, but once started they do not have enough pressure to "blow" them open again.
I found out to my great surprise the CPAP machines were indeed ventilators, in at least technical terms and that while some ventilators do indeed breathe for you, this is not a requirement for being considered a ventilator.
If we look to history, and some marketing cleverness, ventilators have been used in hospitals for a very long time. They were serious and would breathe for critically ill patients. Then came CPAP devices that were meant to be use at home and did not immediately support life (no breathing for you). Most likely some marketing person said "Don't associate CPAP devices with ventilators or some/most people will resist using them, because of course they breathe just fine most of the time."
What is technically accurate or used in a medical class, can and usually is quite different from what is in "common" use.
While this may all be technically interesting, I would suggest that for forum conversations with people new to the CPAP world that we refer to CPAP machines as CPAP machines and for those that do indeed need actual breathing by a machine, they are using ventilators.
For me this was more of an exercise in "hummm I didn't know that" then any need to be accurate.
(04-14-2016, 01:53 PM)justMongo Wrote: The ST stands for Spontaneous-Timed. The patient may initiate switch to IPAP by a Spontaneous breath. If the patient does not initiate a Spontaneous breath by a set time, the machine switches to IPAP on a Timed backup rate.
ST is used for CA; but is not as good as the ASV at treating CA.
If "easybreathe" is a menu option, it will smooth the transitions.
easybreath is not, unfortunately, an option in ST or T mode.
(04-15-2016, 03:57 AM)Asjb Wrote: my opinion, for what it's worth, is that this debate is mostly semantics, and history. The history: I would hazard a guess that my ASV machine is as sophisticated as the 'ventilators' used for critically ill patients in hospital not even 20 years ago. And the machines I remember were about the size of a small wardrobe! But now us (often fit and healthy) people can have the same functionality on our bedside table.
your asv is actually quite a bit *more* sophisticated than the bedside hospital ventilators of old
(04-15-2016, 03:57 AM)Asjb Wrote: Comments (but only non-shouty ones please!) are very welcome.
my shouties should have been italicized for emphasis instead, sorry.
04-16-2016, 05:18 PM
(This post was last modified: 04-16-2016, 05:30 PM by archangle.)
(04-14-2016, 04:23 PM)PoolQ Wrote: Edit: ah well never mind I see that you did indeed include links to Wikipedia, the ultimate source of knowledge in all things. Funny that while in collage we were told specifically that we could not use Wikipedia as a quoted source for what the professor suggested were obvious reasons.
The common statement that "Wikipedia is not a source" is one of the stupidest sayings that gets thrown around today. I could just as easily say "The Journal of the American Medical Association (JAMA) is not a source." Either one is a link to information to be further evaluated, not a guarantee of validity.
A quote from JAMA may very well be the opinion of one researcher that's relevant in a very limited context. It may even be a statement that is not accepted by the medical community in general, but is stated properly as one author's opinion, presumably with some supporting information. It can also be a statement that has since been disproven, rejected, or found out to be outright fraud.
A quote from Wikipedia may be from a well written article with links to exceptionally high quality references to good scientific data. Or, of course, complete garbage. Wikipedia is often a very good staring place to find links to sources. You may find sources that are impeccable.
You may also find sources in Wikipedia that are complete garbage, which is also VERY useful, maybe more useful than good sources in some cases. If the claims that Huha extract helps prevent malignant praxoma comes from someone who also thinks the government is working with the UFO aliens, it gives you a good clue that it's bogus.
Any reference is something that needs to be looked into to decide its legitimacy.
As for the the "Wiki is not a source" and other intellectual rules of college teachers, in the professional world, there is very little that carries less weight than the nitpicking rules of the college classroom.
Get the free SleepyHead software here
for information on the main alternative to CPAP.
If it's midnight and a DME tells you it's dark outside, go and check it yourself.
04-16-2016, 05:53 PM
(This post was last modified: 04-16-2016, 07:31 PM by vsheline.)
(04-15-2016, 10:42 AM)PoolQ Wrote: I personally thought that "of course" CPAP machines are not ventilators as they do not breathe for you.
Exactly right, in my view.
I think it is the ability to do everything needed to breathe for us when we cannot which is the essential characteristic of a ventilator.
In common medical usage a "ventilator" is a machine which is able on its own to cause inhalation and exhalation at a normal respiration rate and without any effort on the part of the patient.
CPAP, APAP and standard BiPAP machines do not have a "backup respiration rate" feature (these machines never initiate inhalation to prevent an apnea) and therefore, in my view, should not be referred to as ventilators.
Yes, yes, I know, perhaps I'm being a bit narrow-minded here... But as an honorary member of the planetary language police, I feel it is my solemn duty to point out proper terminology.
Quote:I have also heard, but not actually done the math myself that CPAP machines do not have enough pressure to breathe for you or even clear an apnea that has already happened. The CPAP machines try and prevent apneas from happening, but once started they do not have enough pressure to "blow" them open again.
Actually, Pressure Support ("PS" is the pressure difference between EPAP and IPAP) of just 10 cmH2O is commonly able to do for us all the work of breathing if we have normal lungs and no obstruction.
In the absence of obstruction, I think it would be a rare patient that would need the ASV machine to use PS higher than 15 cmH2O to do all the work of breathing.
A standard bilevel machine has the strength (but not the programming) to treat central apneas.
Quote:I found out to my great surprise the CPAP machines were indeed ventilators, in at least technical terms and that while some ventilators do indeed breathe for you, this is not a requirement for being considered a ventilator.
I suspect we have relied too heavily on a manufacturer's website which happens to lump together for purposes of discussion all devices for positive pressure therapies.
Quote:While this may all be technically interesting, I would suggest that for forum conversations with people new to the CPAP world that we refer to CPAP machines as CPAP machines and for those that do indeed need actual breathing by a machine, they are using ventilators.
Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment. The Advisory Member group provides advice and suggestions to Apnea Board administrators and staff on matters concerning Apnea Board operation and administrative policies - not on matters concerning treatment for Sleep Apnea. I think it is now too late to change the name of the group but I think Voting Member group would perhaps have been a more descriptive name for the group.
Archangle, I understand what you are saying. I disagree with it, but understand it. We all do what we do. I actually refer to wiki's quite often, I just don't quote them. (you know the internet and all that)
Vaughn, I have been off reading medical journals to learn more about "Patient–Ventilator Interactions" and have yet to find any that differentiate between a ventilator and CPAP,APAP, VPAP, or ASV as all of these are valid modes of operation for ventilators. These limited home use PAP devices can only do a subset of what we refer to as "ventilators" can do. It seems that the medical industry, that does not manufacture PAP machines, only uses the term ventilator for anything that ventilates or assists with breathing. As this is not a medical site, but is an educational site- the common use of CPAP verses ventilator stands, regardless of medical professionals.