CPAPtalk.com

roster wrote:

sleepydawn wrote:I also had the RemStar and now have the S9. I live in the very dry high desert (Boise, ID) and also have never needed a humidifier. I tried it and it made my nose run. I do keep one in case my throat gets dry andI am forced to use a full face mask with a stuffy nose. My insurance paid for it and it makes me feel better to know I have one in case my preferences change. I will use it if I think I need to for comfort.

That is interesting.

Here is a chart showing outdoor humidity levels in Boise - http://www.cityrating.com/cityhumidity.asp?City=Boise

Any idea how it ranges inside your domicile?

No, I'm not sure how it ranges that specifically. I am originally from California so Boise is pretty dry by comparison. But I'm sure it's better than say, Phoenix, where Uncle_Bob lives. I was prone to bloody noses when I was a kid, also in California but I don't have those concerns anymore. My allergies are not as severe here so I'm sure that factors, too.

OutaSync wrote:When I lived in Mountain Home, Idaho (about 60 miles southeast of Boise), it was very, very dry in the summer. The houses were cooled by whole house evaporative coolers. Just adding mositure made it feel 20 degrees cooler.

Specifically, I'm in Meridian. I thinks odds are good that those humidity stats were probably taken down town by the river and as you know that makes a huge difference in temp and humidity! Mountain Home is so brutal in the summer time. I burn to a crisp even with loads of sunblock with the difference in altitude between the Treasure Valley and the Bay Area in California. Still, Mountain Home is even worse than the Boise area. So uncomfortable in the summer time.

wrote: I live in a temperate climate with moderate relative humidity most of the time. But don't forget that forced and unheated airflow is drying over and above the relative humidity levels.

I see that claim often on internet forums. Does anyone have scientific information that this is the case?

My intuition says the reverse is true because,

1. Compress air and the relative humidity of that air actually increases and

2. The air flow in the airways of a person using CPAP is no greater than the air flow when that person is awake and breathing normally.

Some people NEED a humidfier - some people don't. Some people NEED it set higher than others. Some people like and need heated humidity. Some people do better in pass over mode. Some people need humidity at some times of the year and others never.

Bottom line - Some people NEED a humidifier - some people don't!

Hi

Without heated humidity I wake up after 2 or 3 hours with my nasal passage burning same with passive so its heated all the way with me.

I just retested they sent me home with no humidity and I had a terrible nite

Gary

I vote YES to humidity.
This could have been a poll.
It kind of looks like the people who never use humidity are in the very lucky minority.

I don't really understand the question? Humidifier needs are usually determined during the adjustment period along with all the other trial and error settings. I imagine everyone who is using a humidifier has discovered along the way if and when it is necessary for their comfort and symptoms. If they don't require humidity they don't use it.

roster wrote:

wrote: I live in a temperate climate with moderate relative humidity most of the time. But don't forget that forced and unheated airflow is drying over and above the relative humidity levels.

I see that claim often on internet forums. Does anyone have scientific information that this is the case?

My intuition says the reverse is true because,

1. Compress air and the relative humidity of that air actually increases and

2. The air flow in the airways of a person using CPAP is no greater than the air flow when that person is awake and breathing normally.

You are incorrect on your first "intuition".

Relative humidity is not the concentration of water vapour in a volume of air.

Relative humidity is defined as "the ratio of the actual amount of water vapour in the air to the amount it could hold when saturated expressed as a percentage OR the ratio of the actual vapour pressure to the saturation vapour pressure expressed as a percentage." (http://www.bom.gov.au/lam/humiditycalc.shtml) The saturation vapour pressure is directly related to temperature.

According to Charles Law, when you compress a gas (i.e. "air" pressurized by an xpap), the temperature of the gas will rise. As you raise temperature, you increase the saturation pressure for water vapour and you decrease the relative humidity. Thus, when an xpap increases pressure to, say 10 cm h2o above atmospheric pressure, the temperature of that air will increase by some small amount, and the relative humidity of that air will be correspondingly lower. Use of a humidifier can compensate for this reduction in relative humidity. I haven't calculated the effect, but would guess that the actual change due to pressure change is small, perhaps on the order of 5 to 10% relative humidity.

see http://en.wikipedia.org/wiki/Relative_humidity

I had to go one night without it and I was miserable, my throat was sore the next morning and my nasal passages were not happy either.

I would guess Physician is probibly in north part of west coast, or maybe is constantly very hydrated. I can go without humidifier also, but it may cause things I am un-aware of. We use de-humidifier in house in winter to help with wife's allergies. North Oregon coast is fairly high in humidity most of winter. We have dogs in house and need to remove excess moisture at times. Things have been better since aquariums have been given away, they really put the moisture in air. I have been playing with S-9 settings, but left the humidifier part alone until I am totally happy with my low setting on cm. The data capable unit is the only way to go! jlk

I'm in Southeast Iowa. With the humidity we have in Summer, hubby and I use the chambers with water in passover mode. With electric baseboard heat running we both turn the humidifiers on to a low level. If we don't do that we both get sore throats.
Cindy

I live on the East Coast in a very humid area. I never use my humidifier. I'm also frequently too hot at night (I hope that passes eventually lol) so don't like the warmer air blowing on me. I think the humidifier is truly a personal preference thing. The one time I used it I got sick - likely a coincidence but my sinuses suffered horribly.- Kim

Am I an exception?
I have tried two times not using the humidifier. Each time I was blowing my nose and sneezing like crazy all day. I really thought I had a horrible head cold, but those symptoms went away by early evening.

I live near Houston, the most humid place on earth. With the air on all summer and the house closed with little heat on in winter, I find I use it all the time. If I didn't I would die of the sneezies.

I'm in Phoenix where it is very dry (except during Monsoon Season). I'm also prone to nosebleeds (before CPAP) so I'd be reluctant to use my S9 Elite without the humidifier. Somehow the dry air blowing through my nose just seems like it make the nosebleed situation worse.

I live in Honolulu, about 5 minutes from Ala Moana and Waikiki (read very humid) and I use a humidifier. When i've run my bipap without the humidifier my throat and nose were very dry and uncomfortable. One of my friends runs his bipap without it and he has no problems.