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Thanks for the contribution Bill.billbolton wrote:That would be some, not most.Slinky wrote:Most of us end up turning it off, and turning Ramp off too eventually as we get acclimated to and comfortable w/our PAP therapy.
Cheers,
Bill
Wulfman wrote:Yes......potentially.
As has been discussed many times before, EPR drops the pressure on exhale in the number of centimeters according to which setting you select......1 drops 1 cm......2 drops 2 cm......3 drops 3 cm.......for the full exhale period. If the user is prone to having apneas at the point of "end-of-exhale"/"beginning-of-inhale", then you either need to reduce the EPR number or compensate for that with a higher set pressure if you're using CPAP mode or higher minimum pressures if you're using APAP mode.
Den
Physician,Physician wrote:Wulfman wrote:Yes......potentially.
As has been discussed many times before, EPR drops the pressure on exhale in the number of centimeters according to which setting you select......1 drops 1 cm......2 drops 2 cm......3 drops 3 cm.......for the full exhale period. If the user is prone to having apneas at the point of "end-of-exhale"/"beginning-of-inhale", then you either need to reduce the EPR number or compensate for that with a higher set pressure if you're using CPAP mode or higher minimum pressures if you're using APAP mode.
Den
This makes no sense. How does one have apnea with passive expiration ? Partial obstruction, maybe, but not apnea.
The problem CAN occur at the END of the expiration cycle when the exhaled air is no longer keeping the airway open and IF the airway should collapse as the person tries to inhale.......IF the person is susceptible to events at that time.Physician wrote:Wulfman wrote:Yes......potentially.
As has been discussed many times before, EPR drops the pressure on exhale in the number of centimeters according to which setting you select......1 drops 1 cm......2 drops 2 cm......3 drops 3 cm.......for the full exhale period. If the user is prone to having apneas at the point of "end-of-exhale"/"beginning-of-inhale", then you either need to reduce the EPR number or compensate for that with a higher set pressure if you're using CPAP mode or higher minimum pressures if you're using APAP mode.
Den
This makes no sense. How does one have apnea with passive expiration ? Partial obstruction, maybe, but not apnea.
Passive expiration refers to elastic recoil. But as Den mentioned upper airway pressure itself begins to wane as that elastic recoil comes to an end AND expiratory volume has been largely expelled. That's when upper airway closure commonly sets in. So inhalation doesn't even have a chance to get started in some of those cases.Physician wrote: This makes no sense. How does one have apnea with passive expiration ? Partial obstruction, maybe, but not apnea.
"4.3.2.2 IPAP and EPAP should be increased (according to the criterion in Recommendation 4.3.2.1) if at least 1 obstructive apnea is observed for patients <12 years or if at least 2 obstructive apneas are observed for patients ≥12 years (Consensus).
This recommendation is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, a lower pressure is required to treat apneas compared to the pressure required to treat other respiratory events (see Recommendation 4.2.2.2); however, there is 1 level II study and 1 level V study that used increases in both IPAP and EPAP to eliminate apneas.
"4.3.2.3 IPAP should be increased (according to the criterion in Recommendation 4.3.2.1) if at least 1 hypopnea is observed for patients <12 years or if at least 3 hypopneas are observed for patients ≥12 years (Consensus).
This recommendation is based on consensus agreement by the PAP Titration Task Force." -- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2335396/
"Treatment of obstructive sleep apnea with nasal continuous positive airway pressure mandates simultaneous increases of both inspiratory and expiratory positive airway pressures to eliminate apneas as well as nonapneic oxyhemoglobin desaturation events. We hypothesized that the forces acting to collapse the upper airway during inspiration and expiration are of different magnitudes and that obstructive sleep-disordered breathing events (including apneas, hypopneas and nonapneic desaturation events) could be eliminated at lower levels of EPAP than IPAP. To test these hypotheses, a device was built that allows the independent adjustment of EPAP and IPAP (nasal BiPAP). Our data support the hypotheses that expiratory phase events are important in the pathogenesis of OSA and that there are differences in the magnitudes of the forces destabilizing the upper airway during inspiration and expiration. Finally, applying these concepts, we have shown that by using a device that permits independent adjustment of EPAP and IPAP, obstructive sleep-disordered breathing can be eliminated at lower levels of expiratory airway pressure compared with conventional nasal CPAP therapy. This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance." -- http://www.ncbi.nlm.nih.gov/pubmed/2198134