A post for our newer members

[Janyn]

I just wanted to make a post for our newer members that outside factors can effect your therapy as well as the mechanics we all deal with like pressure, mask fit, leaks etc... I have been doing really well with my therapy now that I am 2 months into it but the past 5-6 days have been hell for some reason I was unsure of? I was in between waiting for a medium F20 mask cushion to show up because of leaks with the large size, straps too tight causing issues as well....

These past 5 days I was waking up in the middle of the night feeling like I was drowning and taking the mask off right after my 4 hour compliance time and not feeling like I slept well at all. My AHI was 15.6!!! I also noticed that my machine had gone up to a max pressure of 18.5 cfm. My head felt like it was in a vise and my sinuses were severely blocked. I told my wife I felt like I had a sinus infection. Having some antibiotics still around from the last time I started treatment and within 2 days it was gone and last night for the first time in a week I slept great and kept the mask on for over 7 hours and had an AHI of 1.7!!!

So now looking back I must have been having flow rate issues because of my bad sinus blockage issues. Not sure if this will help anyone but I am very thankful I am back to being able to enjoy the therapy!

[Dormeo]

Thanks for posting this, Janyn. It's a good reminder that all kinds of circumstances can affect our breathing at night, and that problem-solving is a great approach to take.

[Hydrangea]

Such a great reminder!

[mceffi]

Hi, I am a first time user here.

The flow rate that you are talking about here is the CPAP pressure / air flow correct?

Are you using the auto CPAP?

I tought auto CPAP will adjust the flow rate depending on your breathing?

[Sleeprider]

Hi, I am a first time user here.

The flow rate that you are talking about here is the CPAP pressure / air flow correct?

Are you using the auto CPAP?

I tought auto CPAP will adjust the flow rate depending on your breathing?

Pressure and flow are important concepts in CPAP therapy.  Flow is a volume per time function, like mL/second or Liters/Minute. Pressure is measured as cm-H2O.  Positive Air Pressure (PAP) therapy works by using pressure to keep tissues in the airway open to allow for free movement of air during inhale and exhale.  Pressure to inflate a ball, a tire, or a pool toy does not change (static pressure). It can be maintained for long periods with no flow or air additions.  Your airway is more dynamic, but the CPAP machine attempts to maintain constant pressure to keep the airway open, and it uses flow to manage that as you inhale and exhale.  Auto CPAP will increase or decrease pressure based on its programming and conditions measured by its flow and pressure sensors.  Flow increases during inhale to maintain airway pressure, and flow decreases during exhale so pressure does not increase as you exhale.  CPAP flow will increase to replace flow lost due to inspiration, intentional mask leak that vents CO2 and unintentional mask leak.  A large leak will cause a lot of flow to rush through the tube and mask as the machine tries to maintain pressure, but when there is no leak, the only flow is from the mask vent.  In simple CPAP terms, pressure is constant, flow is constant unless there is a leak.

The "flow-rate" we talk about in therapy is the respiratory flow which is not related to pressure.  Tidal volume is the volume of air expired in each respiration cycle in mL/second. We can multiply that by the number of breaths per minute (BPM) to calculate the minute vent in L/min, or the amount of air respired in a minute.  Pressure has nothing to do with respiratory flow other than it helps to keep the airway open and allows for normal breathing in people with airway obstruction at normal atmospheric pressure.

[mceffi]

Hi, I am a first time user here.

The flow rate that you are talking about here is the CPAP pressure / air flow correct?

Are you using the auto CPAP?

I tought auto CPAP will adjust the flow rate depending on your breathing?

Pressure and flow are important concepts in CPAP therapy.  Flow is a volume per time function, like mL/second or Liters/Minute. Pressure is measured as cm-H2O.  Positive Air Pressure (PAP) therapy works by using pressure to keep tissues in the airway open to allow for free movement of air during inhale and exhale.  Pressure to inflate a ball, a tire, or a pool toy does not change (static pressure). It can be maintained for long periods with no flow or air additions.  Your airway is more dynamic, but the CPAP machine attempts to maintain constant pressure to keep the airway open, and it uses flow to manage that as you inhale and exhale.  Auto CPAP will increase or decrease pressure based on its programming and conditions measured by its flow and pressure sensors.  Flow increases during inhale to maintain airway pressure, and flow decreases during exhale so pressure does not increase as you exhale.  CPAP flow will increase to replace flow lost due to inspiration, intentional mask leak that vents CO2 and unintentional mask leak.  A large leak will cause a lot of flow to rush through the tube and mask as the machine tries to maintain pressure, but when there is no leak, the only flow is from the mask vent.  In simple CPAP terms, pressure is constant, flow is constant unless there is a leak.

The "flow-rate" we talk about in therapy is the respiratory flow which is not related to pressure.  Tidal volume is the volume of air expired in each respiration cycle in mL/second. We can multiply that by the number of breaths per minute (BPM) to calculate the minute vent in L/min, or the amount of air respired in a minute.  Pressure has nothing to do with respiratory flow other than it helps to keep the airway open and allows for normal breathing in people with airway obstruction at normal atmospheric pressure.

Good explanation 

[Janyn]

Thank you for that great explanation. Yes that is what I was referring too, I just wanted to let our newer folks know that external factor can and will effect your success and failure rates. I am learning as I go, and so many here have helped me, just trying to give back a little

[mceffi]

Thank you for that great explanation. Yes that is what I was referring too, I just wanted to let our newer folks know that external factor can and will effect your success and failure rates. I am learning as I go, and so many here have helped me, just trying to give back a little

Thank you

[MarineCorpsNerd1]

Good post. We have problems with airflow and Co2 here, it's been dropping people pretty consistently.