Having read the advertising copy at the link, I can say that I've got mixed feelings about what's being claimed.
After talking at length about how V-Com "reduces inspiratory pressure" and how this is supposed to relieve anxiety of newbies and make learning how to breathe with an xPAP easier, the ad goes on to say:
During typical breathing, you’re actively inhaling, and then you relax and passively exhale. But let’s say I put you on 15 centimeters of CPAP and I pharmacologically sedated and paralyzed you, the CPAP machine would inflate your lungs and hold them there—it would hold the lungs distended. That illustrates the fact that when you go on CPAP, you’re actively having to resist the pressure forcing the air in.
This phenomenon is exactly why
expiratory relief was invented: EPR and Flex are designed to make it easier to
exhale against the positive air pressure.
And, to use their own example of putting someone who is pharmacologically sedated and paralyzed on CPAP, having the pressure reduce from 15 to 12 when the patient has stopped inhaling would encourage the lungs to deflate very slightly allowing a bit of "passive" exhalation to take place.
Now having said all that, it's also true that for some newbies (and I was one of them), the fact that CPAP can feel like it's pumping more air than you want to inhale does in fact create some real anxiety and some real problems. In my case I felt like a goose being force-fed for the creation of foie gras. And all that "too much air" on inhalation triggered swallowing of air which led to some really bad aerophagia, which in turn allowed an insomnia monster to move into my bedroom.
When I was switched to a PR BiPAP, I found that by turning Bi-Flex off and turning Rise Time to 3 (its maximum setting), the change to inspiratory pressure that now occurred over 3/100 of a second no longer felt like I was being forced to inhale more air than I could possibly inhale. And that (plus a lower IPAP than my original fixed CPAP pressure) was enough to take the edge off things. Even so, it took me months of hard CBT-Insomnia to fight and defeat the insomnia monster in my bedroom. (And even 12 years later, I still have to be vigilant about keeping that insomnia monster at bay.)
Resmed VPAPs and VAutos also have settings that allow you to control how fast the pressure goes back up to IPAP. If you are using VAuto mode the "Trigger" setting essentially controls how quickly the machine transitions from EPAP to IPAP. If you are using S mode, then "Trigger" and/or "Rise Time" can both be used to fine tune the way the machine increases the pressure from EPAP to IPAP.
Now as near as I can tell, the ad for V-com seems to be saying that it can make the change from expiratory pressure to inspiratory pressure "more comfortable" for new xPAP users. I can't help but suspect that the "feel" of V-Com could be achieved on a bi-level machine by playing around with the Trigger and/or RiseTime settings along with a modest changes in the PS and/or IPAP settings.
I'm also skeptical about the ad's claim that a reduction of the set pressure when using EPR or Flex is not going to provide the same kind of "relief" as V-Com: The ad claims:
The other question I get frequently is, “Can’t you just turn the pressure down for the same effect as V-Com?” But if you turn the pressure down, then you’re decreasing both inspiratory and expiratory pressure while increasing the likelihood of respiratory events. The V-Com decreases the inspiratory, the offending pressure, but it preserves the therapy of the expiratory.
If your set pressure is 9 cm and you are using EPR = 3, then your expiratory pressure is 6 cm. If you want to reduce the inspiratory pressure to 8cm and keep the expiratory pressure the same, all you need to do is reduce EPR = 2. Similarly with flex, although Flex is not a straightforward reduction in pressure. But even so, if you start with a pressure setting of 9cm and Flex = 3, then your expiratory pressure is typically between 6 and 7, and usually closer to 7. So decreasing the pressure to 8cm and setting Flex = 2 is still going to keep that expiratory pressure between 6 and 7, although it may be closer to 6 on more breaths.
The ad goes on to say:
What about bilevel devices–do they have a setting to decrease inspiratory pressure only?
No, they don’t. No positive airway pressure device has a feature to drop inspiratory pressure only.
This is pure malarkey.
On a Resmed VPAP or VAuto, the PS setting controls the relationship between IPAP and EPAP. If IPAP = 10 and PS = 4, your expiratory pressure is 6cm. If you reduce IPAP to 9 and use PS = 3, then IPAP is now 9 and EPAP is still at 6.
On a PR BiPAP, IPAP and EPAP are separate settings. So if you start at IPAP = 10 and EPAP = 6 and change the settings to IPAP = 9 and EPAP = 6, you've decreased just the inspiratory pressure only.
On a PR BiPAP Auto, the situation is just a bit murkier, but you can still effectively reduce IPAP while keeping EPAP at its original level. It would involve appropriately setting both the PS min and PS max settings. If you start with min EPAP = 5, max IPAP = 12, min PS = 3, and max PS = 5, then you start off with IPAP/EPAP = 8/5. You might eventually reach 12/9 if the machine detects the right combination of events. But when IPAP = 12, it's also possible that EPAP could be as low as 7 = 12 - 5.
If you want to reduce IPAP by 1cm while leaving EPAP the same, then you'd need to change the settings to min EPAP = 5, max IPAP = 11, min PS = 2, and max PS = 4. Those settings cause you to start off with IPAP/EPAP = 7/5. You might eventually reach 11/9 if the machine detects the right combination of events. But when IPAP = 11, it's also possible that EPAP could be as low as 7 = 11 - 4.
So in any case, changing the settings effectively reduces IPAP without reducing EPAP.
I'll have to read the "clinical notes" more carefully to see what they're actually saying about how V-com "works" to figure out why they seem to think this is different than setting RiseTime on a PR BiPAP or some combination of RiseTime and Trigger on a Resmed VPAP or VAuto.
