Because AVAPS (not prior VAPS) will only change IPAP at a rate of less than 1cm per minute. CSR needs to have individual breaths very quickly and fluidly corrected with individual pressure swings as high as IPAP max.Banned wrote:Why wouldn't AVAPS with an assured volume be a better alternative for Cheyenne-Stokes respiration than an SV?
Well, prior VAPS comes much closer to that functional description than gradual AVAPS (the latter limited to those very gradual IPAP deltas at less than 1cm per minute). And I think SV design and scope of application are bound to evolve.Banned wrote: And why wouldn't they make an SV with an assured volume
Gradual AVAPS is designed to make slow IPAP adjustments to fix temporary long-haul conditions: 1) temporary or transient acute COPD exacerbations, 2) positional mechanical "overloading" in obesity related hypoventilation, 3) transient or temporary changes in pulmonary-related neuromuscular rigidity or dyscontrol, etc.
Gradual AVAPS changes are intended to address the above changing conditions or sudden "stepped states" in physiology. But those gradual AVAPS changes are not responsive enough on a "per-breath" basis to rapidly address PB, CSR, or other issues that need highly fluid individual breath corrections (those conditions requiring fluid respiratory controller gain compensation).