+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: how do i slow down the surges? (/Thread-how-do-i-slow-down-the-surges)
how do i slow down the surges? - fdashiell - 10-04-2020
My ResMed S9 is surging faster than I breathe. How do I slow this down?
RE: how do i slow down he surges? - staceyburke - 10-04-2020
I don’t know if the s9 has this but it is calls ti max and min. This is what is in wiki on this site. BTW the s10 does have this.
Respiratory cycle determination
Determination of the inspiratory and expiratory cycles is essential not only to provide bilevel PAP but also for expiratory pressure relief and determination of inspiratory flow limitation in auto algorithms. The start of inspiration is marked by a switch from negative to positive flow (relative to baseline). The point at which the flow signal switches from positive to negative flow is the start of expiration. SV and some auto devices use more continuous respiratory cycle determination. ResMed’s servoventilator microprocessor uses fuzzy inference rules looking at the flow rate (relative to mean flow), direction, and size to determine the phase of the respiratory cycle9 (Table 1). Respironics’ servoventilator determines the length of inspiration and expiration of recent breaths to predict the future breath duration and divides the breaths into short time segments (64 ms) to determine the expected mid-inspiration and other points of the cycle.10
RE: how do i slow down he surges? - fdashiell - 10-04-2020
Which parameter in the settings should I change, and which direction to slow down the surges?
RE: how do i slow down he surges? - staceyburke - 10-04-2020
Might be a trial and error. But you can go back and change it again, no big deal. If I were guessing I would think min.
RE: how do i slow down he surges? - Sleeprider - 10-04-2020
Stacey, this is the S9 VPAP Adapt which is the ASV. There are only pressure settings.
fdashiell, we need to know your current settings for mode, EPAP min, EPAP max, PS min, PS max. It would be more helpful if you would download and install the free OSCAR program which will give us the settings as well as detailed therapy information. Finally, are you treating complex or central apnea or some other condition? Why are you using the VPAP adapt?
RE: how do i slow down he surges? - Gideon - 10-04-2020
Is it too much too soon on the inhale, or is the exhale overlaping onto your next breath?
It makes a difference as to which parameter is adjusted.
RE: how do i slow down he surges? - staceyburke - 10-04-2020
Thanks sleeprider
RE: how do i slow down he surges? - fdashiell - 10-05-2020
sleeprider --- I have uploaded a screenshot of OSCAR data.
RE: how do i slow down he surges? - fdashiell - 10-05-2020
bonjour --- the surges are coming at least 2x my normal breathing rate. The next surge is way too close to the finidh of the previous surge. Can you tell me the parameters for each of the scenarios that you outlined. Thanks.
sleeprider
My current diagnosis 9/1/2020 is OSA, It was CSA, thats why I have the unit I have. Doc rec 11cm CPAP.
RE: how do i slow down he surges? - Sleeprider - 10-05-2020
The summary statistics show your recent night was using CPAP mode at a pressure of 11.0. Prior to that you used ASVauto mode with EPAP min 5.0 and PS 3.0 to 10.0. It appears your EPAP max is about 9.0 cm based on the summary statistics. It will be very helpful if you can post a daily details chart as shown in the how to organize your Oscar charts wiki, so we can see some clues from your detailed results and especially your respiratory rate, tidal volume and minute vent. http://www.apneaboard.com/wiki/index.php?title=OSCAR_Chart_Organization Note that there are two different views you can set in the View Menu, Standard and Advanced. Both of those views will be useful in evaluating your ASV. The Standard view will show events, flow rate, pressure, leaks, flow limitations, and the Advanced view will show events, flow rate, mask pressure, tidal volume and minute vent.
Your S9 VPAP Adapt has no settings to affect the respiratory timing or volume. It targets maintaining your respiratory rate and volume by using the previous 90 seconds of therapy as a target to maintain respiration. A machine that feels like it is pacing too fast is usually the result of starting therapy before your respiration rate has time to settle down from being away. The more rapid, deeper breathing as you begin to use the machine becomes a target rate and volume that is not needed as you approach a sleep state. It is important to give yourself time when you go to bed for respiration to settle before putting on the mask. There are several things you can do to control and tame the machine. First, you should be sure you are relaxed and breathing has normalized before putting on the mask. Second, you can do what many ASV users call the "blow-back technique". When the machine feels like it is not in sync, use a couple assertive blow-backs to reset the machine that you are spontaneously controlling the breath rate. While we don't normally like ramp with ASV, it is a way to get past the sleep transition where respiration can be more chaotic, so using a ramp of 20 minutes may help.
The ASV is designed to follow your spontaneous breathing rate and to start backup breaths when that rate in breaths per minute falls 20% below the previous 90 second rate. Similarly, it applies more pressure support to maintain the minute vent (air volume in L/min). In CPAP mode which you tried on October 3, no pressure support is used, and you only receive fixed pressure. Using CPAP your AHI was near 5.0 and presumably that is because you have central apnea that are not treated by CPAP. Your results with ASV are clearly better.
Before making some setting suggestions for improving your comfort with ASV auto mode, I'd like to see some detailed charts from your prior use of ASV auto. Meanwhile, keep in mind how this machine works, why your are experiencing poor sync, and what you can do to control it.