C-flex question

[inernest]

Hi everyone,
I've searched through the forum and can't find a specific answer about c-flex.

When I go to sleep, my machine feels like it's blowing full blast (my pressure is 10).
After a couple of breaths, I can feel the c-flex kicking in and exhaling is much easier, but the pressure during my inhale seems the same. If I open my mouth, air comes blasting out of my mouth making it difficult to talk.

When I wake up in the morning, I feel like there is virtually no airflow. I can actually open my mouth and no air blows out.

Is this normal?
How do I know I'm getting enough pressure?

[yardbird]

Hi everyone,
I've searched through the forum and can't find a specific answer about c-flex.

When I go to sleep, my machine feels like it's blowing full blast (my pressure is 10).
After a couple of breaths, I can feel the c-flex kicking in and exhaling is much easier, but the pressure during my inhale seems the same. If I open my mouth, air comes blasting out of my mouth making it difficult to talk.

When I wake up in the morning, I feel like there is virtually no airflow. I can actually open my mouth and no air blows out.

Is this normal?
How do I know I'm getting enough pressure?

c-flex is not "ramp". Ramping, when enabled, has the machine start out at a lower pressure and slowly build to your set pressure over a set time period.
SO... c-flex makes exhaling easier. It does NOTHING for inhaling which should be at your set pressure (unless during the ramp period... see above)

When you open your mouth, air comes blasting out making it difficult to talk.
Don't talk. Air will come out. This is entirely normal.

You can open your mouth and no air comes out in the morning.
Your internal air tank is empty. (just kidding)... actually, with the CPAP blowing air into your nose, it is still possible to simply open your mouth and NOT have air come out. This depends on what the back of your throat is doing. In "swallow" mode, the air passage is closed to allow you to swallow. In "talk" mode, the air passage is open to allow air to go through your vocal chords to create sound. This can also open the path between your nose and your mouth. If the air pressure required to talk is lower than the air pressure going into your nose.... your nose wins and air comes rushing out your mouth. IF, however, you were to SHOUT REAL LOUD and thus create pressure-to-talk that is greater than pressure-going-into-nose-from-machine.... then SHOUTING WINS AND YOU'LL BE ABLE TO SHOUT.

This is just a function of the marvelous mechanics of the human body.

So... with the machine on... don't talk.

Also... if you inadvertently get into "swallow mode" while sleeping, it is possible to have the machine inflate your belly like a balloon. This is sometimes painful, but it too shall pass.... making for some hysterically funny breakfast table entertainment.

[inernest]

Thanks,
I guess I'll rephrase my observations and questions a bit for clarification.

I have a CPAP, and not an APAP.
I do not use the ramp function on my machine when falling asleep, and I'm aware of how it works.

I am noticing quite a difference in the volume of airflow between when I go to bed and when I wake up. When I go to bed it seems quite strong. When I wake up it seems rather weak. Kind of like the difference between a faucet with the tap all the way open and just cracked to a drizzle.

I do realize that flow is not the same as pressure, and that they can change independently from each other.

Is this effect related to my c-flex setting?
How do I know my machine is continuing to provide the proper pressure even when the flow seems very low?

(I do not have a card reader or software and am unlikely to purchase one.)

[JeffH]

The air volume hasn't changed, you've just become used to it in the night. This is completely normal.

[Eureka]

inernest --
I have noticed the same feeling in the mornings -- that the air pressure is very weak. I am on an auto but set for straight cpap -- and the presssure is the same as yours - 10 cm. After I read your reply I looked at my charts and it shows that the pressure never varies - always at 10 cm. My cflex is set on **1** - don't know where your's is set. I guess it must be my perception of the pressure becoming weaker because the charts show it remains at 10. I am glad you made the observation for I had thought the same, but hadn't actually formalized my thinking on it.

CLW

[JeffH]

There will come a time when you start it up and it will feel like not much pressure. I'm running 12.5 now and hardly notice it when I strap up.

JeffH

[elader]

When I start up the machine at night, it blasts too. Takes a couple of breaths to stabilize. I also wake up thinking "is this thing on?". But it is. No worries.The cflex just drops the pressure a bit for your exhale and cranks back up at the tail end of your exhale.