Is expiratory pressure relief similar to BiPAP on lower pressure settings?

[drmaestro]

Hi,

As the title mentions, I am trying to understand if EPR is similar to what a BiPAP achieves at similar pressure levels. EPR allows you to decrease the expiratory pressure between 1-3 cm H2O. A BiPAP has a wider range apparently, so it can go higher than 3 cm H2O between inspiration and expiration. So, if you need high inspiratorty pressures but considerably lower expiratory pressures, a CPAP won't be able to provide this option, however if you don't need very high levels of inspiratory pressures, then a 1-3 cmH2O difference could be all you need. Assuming this is the case, would a auto CPAP with EPR function exactly in the same way as a BiPAP device or is there a difference in how a BiPAP functions?

Thanks...

[Illorum]

Yes, EPR is essentially just limited BiPAP.

[Sleeprider]

EPR is identical to pressure support, so and Autoset at 7.0 cm with EPR 3 (7/3) is identical to an Aircurve 10 at 4.0 with PS 3 (7/3). The minimum pressure on any of these machines is 4.0 cm, and using EPR at a minimum pressure that results in an EPAP less than 4.0 will not be effective.

[Gideon]

The function is different, EPR subtracts from IPAP/Inhale/Pressure, whereas PS adds to the EPAP/Exhale pressure.

So Yes, as long as you view the resulting pressures after EPR or PS is applied. This means that you must account for the change in EPAP when EPR is applied

[Dormeo]

We stand at the ready to explore this further if you want to say more about why you're curious.

[drmaestro]

The reason I was curious was that if it is the same option but in limited range, while would it be limited? Why cripple the option, if there is no difference on how the unit works.

[redlegs]

The function is different, EPR subtracts from IPAP/Inhale/Pressure, whereas PS adds to the EPAP/Exhale pressure.

So Yes, as long as you view the resulting pressures after EPR or PS is applied.  This means that you must account for the change in EPAP when EPR is applied

The wording here confuses me a bit. I know EPR basically just lowers the pressure that's already being sent your way. On a Bilevel it doesn't subtract it just switches to the epap pressure?

[Gideon]

EPR/CPAP subtracts from pressure.  You want a pressure of 8, 8 is working well for you as CPAP.  You apply EPR of x, let's say 3, and your EPAP, which is what manages Obstructive Apnea, drops to 5 resulting in an unintended increase in obstructive events.  This action results in 8/5

With a BiLevel you have an EPAP of 8 and apply a PS of 3, same as above the IPAP then becomes 11 so the results are 11/8,  considerably different.

What need to occur is to increase your CPAP pressure from 8 to 11 and apply the EPR of 3 resulting in the same 11/8 thus maintaining tye same EPAP (and IPAP) with both machines.

[slowriter]

The reason I was curious was that if it is the same option but in limited range, while would it be limited? Why cripple the option, if there is no difference on how the unit works.

So they can charge (much) more for a unit without that restriction.

[redlegs]

EPR/CPAP subtracts from pressure.  You want a pressure of 8, 8 is working well for you as CPAP.  You apply EPR of x, let's say 3, and your EPAP, which is what manages Obstructive Apnea, drops to 5 resulting in an unintended increase in obstructive events.  This action results in 8/5

With a BiLevel you have an EPAP of 8 and apply a PS of 3, same as above the IPAP then becomes 11 so the results are 11/8,  considerably different.

What need to occur is to increase your CPAP pressure from 8 to 11 and apply the EPR of 3 resulting in the same 11/8 thus maintaining tye same EPAP (and IPAP) with both machines.

OK if ipap and epap are both at 8 and you set PS to 4 IPAP would then become 12 IPAP and 8 EPAP? and if its an auto bilevel there'd always be a difference of 4 cm h2o between ipap and epap up to 25 ipap -21 epap?