Machine is hyperventilating me!

[Josephdfco]

He told me I'd be just as uncomfortable with an ASV. Is this true?

[Shin Ryoku]

He says its the right machine, that asv isn't always the best choice for complex. He says I need to keep trying, that he'll see me in 2 months. He says they may be able to tweak it a little here and there as needed. I don't know, he's wearing a Yale school of medicine lab coat, but I can't help being frustrated and wondering if he has all the information. I can't imagine being able to sleep the way that machine was initially set up. Even on ivaps, which was better, I had to screw around with it for a couple hours before I could sleep.

I'm a physician though not a sleep specialist.  Nothing I can find in the literature supports the use of BPAP over ASV in the treatment of central sleep apnea.  For treatment-emergent CSA specifically, there seems to be inadequate evidence to support the choice of one over the other.  Some excerpts from UpToDate:


Mode selection for positive airway pressure titration in adult patients with central sleep apnea syndromes

Authors
Tomasz J Kuzniar, MD, PhD, FCCP, FAASMAssistant Professor of MedicineNorthShore University HealthSystem, University of ChicagoNeil Freedman, MDHead, Division of Pulmonary, Critical Care, Allergy and ImmunologyNorth Shore University Health System

BPAP therapy is an option when used in the spontaneous timed (ST) mode targeted to normalize the apnea-hypopnea index (AHI)... In patients with hyperventilation-related CSA that is not due to heart failure, trials of BPAP are typically reserved for those who have failed or not tolerated trials of CPAP and ASV.  In these patients, BPAP should only be used with a back-up respiratory rate because BPAP without a back-up rate may exacerbate hyperventilation, hypocapnia, and central apnea by augmenting the tidal volume [36,37].

Treatment-emergent central sleep apnea

Author
Sairam Parthasarathy, MDAssociate Professor of MedicineUniversity of Arizona

BPAP with a backup rate can also lower the AHI compared with levels during CPAP initiation in patients with treatment-emergent CSA, at least initially [23,31,34].

Small trials have demonstrated that BPAP with a backup rate and ASV perform similarly, although re-emergence of central apneas might be of concern with BPAP with a backup rate...

Central sleep apnea: Treatment

Author
M Safwan Badr, MDSection Editor — Sleep Related Breathing DisordersProfessor and Chief, Pulmonary Critical Care and Sleep MedicineWayne State University School of Medicine

In patients with hyperventilation-related CSA that is not due to heart failure, trials of BPAP are typically reserved for those who have failed or not tolerated trials of CPAP and ASV. In these patients, BPAP should only be used with a back-up respiratory rate because BPAP without a back-up rate may exacerbate hyperventilation, hypocapnia, and central apnea by augmenting the tidal volume [36,37].

[Josephdfco]

He says its the right machine, that asv isn't always the best choice for complex. He says I need to keep trying, that he'll see me in 2 months. He says they may be able to tweak it a little here and there as needed. I don't know, he's wearing a Yale school of medicine lab coat, but I can't help being frustrated and wondering if he has all the information. I can't imagine being able to sleep the way that machine was initially set up. Even on ivaps, which was better, I had to screw around with it for a couple hours before I could sleep.

I'm a physician though not a sleep specialist.  Nothing I can find in the literature supports the use of BPAP over ASV in the treatment of central sleep apnea.  For treatment-emergent CSA specifically, there seems to be inadequate evidence to support the choice of one over the other.  Some excerpts from UpToDate:


Mode selection for positive airway pressure titration in adult patients with central sleep apnea syndromes

Authors
Tomasz J Kuzniar, MD, PhD, FCCP, FAASMAssistant Professor of MedicineNorthShore University HealthSystem, University of ChicagoNeil Freedman, MDHead, Division of Pulmonary, Critical Care, Allergy and ImmunologyNorth Shore University Health System

BPAP therapy is an option when used in the spontaneous timed (ST) mode targeted to normalize the apnea-hypopnea index (AHI)... In patients with hyperventilation-related CSA that is not due to heart failure, trials of BPAP are typically reserved for those who have failed or not tolerated trials of CPAP and ASV.  In these patients, BPAP should only be used with a back-up respiratory rate because BPAP without a back-up rate may exacerbate hyperventilation, hypocapnia, and central apnea by augmenting the tidal volume [36,37].

Treatment-emergent central sleep apnea

Author
Sairam Parthasarathy, MDAssociate Professor of MedicineUniversity of Arizona

BPAP with a backup rate can also lower the AHI compared with levels during CPAP initiation in patients with treatment-emergent CSA, at least initially [23,31,34].

Small trials have demonstrated that BPAP with a backup rate and ASV perform similarly, although re-emergence of central apneas might be of concern with BPAP with a backup rate...

Central sleep apnea: Treatment

Author
M Safwan Badr, MDSection Editor — Sleep Related Breathing DisordersProfessor and Chief, Pulmonary Critical Care and Sleep MedicineWayne State University School of Medicine

In patients with hyperventilation-related CSA that is not due to heart failure, trials of BPAP are typically reserved for those who have failed or not tolerated trials of CPAP and ASV. In these patients, BPAP should only be used with a back-up respiratory rate because BPAP without a back-up rate may exacerbate hyperventilation, hypocapnia, and central apnea by augmenting the tidal volume [36,37].

So, ST is an acceptable treatment modality IF CPAP and ASV are tried, and fail?  Why do I keep getting the feeling that the VA is trying to save a buck?

[Sleeprider]

I think you need do nothing more than read the conditions the manufacturer has obtained FDA approval for a particular machine. Nothing suggests the ST is appropriate therapy for central apnea or opioid centrals, while ASV is targeted specifically at those groups.

[Shin Ryoku]

Nothing suggests the ST is appropriate therapy for central apnea or opioid centrals, while ASV is targeted specifically at those groups.

Here are a some more references re: CSA and BPAP.  Click the green numbers to see the references.

BPAP with a backup respiratory rate — BPAP with a backup rate can also lower the AHI compared with levels during CPAP initiation in patients with treatment-emergent CSA, at least initially [23,31,34].
Small trials have demonstrated that BPAP with a backup rate and ASV perform similarly, although re-emergence of central apneas might be of concern with BPAP with a backup rate:
●In a randomized trial that included nine patients with treatment-emergent CSA, ASV reduced the AHI from 52 to 1 event per hour, while BPAP with a backup rate reduced the AHI from 52 to 6 events per hour [31].

●In a larger randomized trial that included 30 patients with treatment-emergent CSA, both ASV and BPAP reduced the first-night AHI (28 to 9 events per hour and 29 to 9 events per hour, respectively); however, there was re-emergence of central events in the BPAP group after six weeks [29]. This observation requires further study and independent confirmation.

PATIENTS WITH CSA AND OPIOID USE — Treatment of this population involves the administration of positive airway pressure (PAP) therapy while the dose of medication is being lowered or discontinued. The phenotype of sleep-disordered breathing in opioid users differs from central sleep apnea (CSA) due to other conditions. Central apneas, ataxic breathing, prolonged obstructive hypopneas, and hypoventilation can all be seen [35]. For that reason, in most cases, bilevel PAP (BPAP) modalities (eg, adaptive servo-ventilation [ASV] or BPAP in the spontaneous/timed [S/T] mode) is used with better success than continuous PAP (CPAP), which is typically insufficient to fully control sleep-disordered breathing in this population. However, data directly comparing these modalities are sparse, and most data come from small case series and our experience [33,36-38]. In patients whose central apneas are due to opioid use and cannot be controlled to reach an apnea-hypopnea index (AHI) <5 by CPAP, ASV with an auto-titrating expiratory pressure is typically the first-line mode of PAP therapy. For those who fail ASV, we perform titration of BPAP-S/T. In patients with CSA due to opioids, we monitor transcutaneous carbon dioxide (CO2) levels, a measure of hypoventilation, throughout the polysomnogram, although this technology is not always feasible and this approach is unproven. (See "Sleep-disordered breathing in patients chronically using opioids".)

Available data on BPAP in patients with CSA includes two uncontrolled trials and one nonrandomized controlled trial of BPAP with a back-up respiratory rate in patients with CSA due to heart failure [33-35]. A meta-analysis of these three trials reported a mean decrease in the AHI of 44 events per hour [2]. In addition, improved exercise capacity was reported with BPAP in the only trial that measured this outcome [34]. There is a paucity of data regarding the effects of BPAP in patients with hyperventilation-related CSA other than CSA due to heart failure. (See "Central sleep apnea: Pathogenesis", section on 'Central apnea due to hyperventilation'.)

In patients with hyperventilation-related CSA that is not due to heart failure, trials of BPAP are typically reserved for those who have failed or not tolerated trials of CPAP and ASV. In these patients, BPAP should only be used with a back-up respiratory rate because BPAP without a back-up rate may exacerbate hyperventilation, hypocapnia, and central apnea by augmenting the tidal volume [36,37]. Titration of BPAP in patients with CSA is reviewed in more detail separately.

Safe to say it's not a first line treatment option, but there are some data to support its use.

[Walla Walla]

A BiPAP with backup respiratory rate can be used but it is not the preferred method for Centrals. If an ASV can be used than that's the one that should be used. In this case it sounds like an ASV should be used.

[Sleeprider]

Shin, thanks for the well-considered research and references!

[Shin Ryoku]

A BiPAP with backup respiratory rate can be used but it is not the preferred method for Centrals. If an ASV can be used than that's the one that should be used. In this case it sounds like an ASV should be used.

From my reading, the usual treatment approach for centrals (outside of low EF heart failure) is that CPAP is first line (and/or supplemental oxygen as appropriate), ASV is second line, and BPAP with backup rate is third line.  So it does seem curious that they are skipping ASV and going to BPAP with backup rate.

On the other hand, I think it is very unlikely that a Yale SOM doctor would knowingly prescribe a less effective machine for financial reasons.  We're not talking 10x less expensive or something where the medical literature discusses cost effectiveness.  IMO, it's more likely that he either made a mistake and prescribed the wrong machine, that he knows something we don't know, or that he has a different "expert opinion" based on something or other...

[Josephdfco]

Yes, thank you Shin, Sleeprider, and all the others who have helped! Now I need to figure out what's best to use for the night, unless you think I should just stick with what I ended up with last night?

[Walla Walla]

A BiPAP with backup respiratory rate can be used but it is not the preferred method for Centrals. If an ASV can be used than that's the one that should be used. In this case it sounds like an ASV should be used.

From my reading, the usual treatment approach for centrals (outside of low EF heart failure) is that CPAP is first line (and/or supplemental oxygen as appropriate), ASV is second line, and BPAP with backup rate is third line.  So it does seem curious that they are skipping ASV and going to BPAP with backup rate.

On the other hand, I think it is very unlikely that a Yale SOM doctor would knowingly prescribe a less effective machine for financial reasons.  We're not talking 10x less expensive or something where the medical literature discusses cost effectiveness.  IMO, it's more likely that he either made a mistake and prescribed the wrong machine, that he knows something we don't know, or that he has a different "expert opinion" based on something or other...

It may be a Yale graduate Doctor but he's working for the VA. With the politics moving towards cutting back disability for sleep apnea in the military I won't be suprised if it's also affecting the VA policies. But your right who knows.