Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.
Login or Create an Account
I have a borrowed AVAPS machine that I'm using for its backup breath rate (and not for a pulmonary condition) to deal with central apnea. My chart shows a huge amount of backup breaths, sometimes completely dominating the breathing as shown in the zoomed-in view. Is this as abnormal as I think it is? Would an ASV machine do anything different?
(By the way, I see the 15.85 mask pressure bug and have since updated the machine's firmware to 1.06. I'll know tomorrow whether that fixes it.)
Machine: Lowenstein Luisa Mask Type: Full face mask Mask Make & Model: Resmed Quattro FX Humidifier: separate F&P humidifier CPAP Pressure: Epap 4-20 PS 4-20; "auto" rate CPAP Software: Not using software
Other Comments: Using 45 degree angle upper body wedge (36"x36") and 4.5"soft cervical collar; 500 assured tidal vol
You have one setting called, "timed inspiration". It is set to 2 seconds. Have your tried tweaking this up or down to see how that affects your OSCAR charts?
ASV is similar to AVAPS with a back up rate, but instead of a back up rate at, say, 12 (provides a breath every 5 seconds all night long); the ASV uses a 3 minute rolling average (recalculates continuously) during the night to determine the back up rate. It starts with the first 3 minutes when a person masks up and starts the ASV.
The "dynamic" back up rate of ASV can change during the night if your spontaneous breathing gets either: 1. slower (then the 3 minute rolling average would be dragged down a little bit - maybe from 12 to 11 or even 10 as an example). 2. faster (the 3 minute rolling average would be increased a little bit (ie: from 12 to 13 or even 14, etc.).
This, plus AVAPS has an "assured" tidal volume every breath that the ASV does not have. It calculates a tidal volume for you by its 3 minute rolling average and can change your tidal volume target during sleep as well.
Advisory Members serve as an "Advisory Committee" to help shape Apnea Board's rules & policies.
Membership in the Advisory Members group does not imply medical expertise or qualification for advising Sleep Apnea patients concerning their treatment.
Jay51: The parameter that Oscar labels as "Timed Insp." is called "Inspiratory Time" in the DreamStation manual. The range is 0.5 to 3.0 seconds. I think this is the time period in which the flow is positive during a machine-triggered breaths. The machine triggers a breath if the patient hasn't taken a breath in the time-out period (currently set to 5 seconds). The manual says it "will enforce a set minimum breath rate by, if necessary, providing machine (time) triggered breaths. For these breaths, the inspiratory time is also a set value."
coutherino: Although you haven't commented yet, I gather from your other posts that excessive machine ventilation suppresses spontaneous breathing by driving the CO2 too low. That seems right. So maybe I should lower the BPM from 12 to 10, which means it will wait 6 seconds instead of 5 before stepping in to breath for the patient. And I could lower the tidal volume from 550 to say maybe 500.
Hello, I saw your message. ASV, AVAPS, BiLevel ST (and central apnea as a whole really) is definitely the area where I most lack knowledge. I'm not sure how much help I'll be. Jay51 is uh, definitely a lot more knowledgeable than me on this subject. I have no experience with any of those machines beyond surface level stuff, so out of fear of saying anything ignorant or unhelpful I'm just gonna refrain...
Machine: Lowenstein Luisa Mask Type: Full face mask Mask Make & Model: Resmed Quattro FX Humidifier: separate F&P humidifier CPAP Pressure: Epap 4-20 PS 4-20; "auto" rate CPAP Software: Not using software
Other Comments: Using 45 degree angle upper body wedge (36"x36") and 4.5"soft cervical collar; 500 assured tidal vol
Advisory Members serve as an "Advisory Committee" to help shape Apnea Board's rules & policies.
Membership in the Advisory Members group does not imply medical expertise or qualification for advising Sleep Apnea patients concerning their treatment.
Here are last night's results with the backup timeout lengthened from 5 to 6 seconds, and the backup tidal volume dialed down from 550 to 500. Huge change: Vastly reduced machine-triggered breaths. Much improved AHI. And I feel a lot better today. Although a single night is far from definitive, it seems like progress. (And the firmware update fixed the mask pressure bug.)
All you Oscar examiners are urged to jump in with your analysis.
Machine: Lowenstein Luisa Mask Type: Full face mask Mask Make & Model: Resmed Quattro FX Humidifier: separate F&P humidifier CPAP Pressure: Epap 4-20 PS 4-20; "auto" rate CPAP Software: Not using software
Other Comments: Using 45 degree angle upper body wedge (36"x36") and 4.5"soft cervical collar; 500 assured tidal vol
Great improvement. It took me many months to get all the EVO ventilator settings tweaked just right.
You are still having a lot of H's though. Usually, increasing pressure support (difference between epap and ipap) stops H's. Also, trying the techniques for positional apnea might help to stop the H's as well: lowering your pillow height, side sleeping instead of back sleeping, and even trying a soft cervical collar.
Advisory Members serve as an "Advisory Committee" to help shape Apnea Board's rules & policies.
Membership in the Advisory Members group does not imply medical expertise or qualification for advising Sleep Apnea patients concerning their treatment.
