Modified Adaptive Servoventilation (ASV) Compared to Conventional ASV

Study Overview
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Brief Summary
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This study will determine if modified adaptive servoventilation (ASV) is as effective as the conventional ASV in treating periodic breathing. The study will determine if the modified ASV reacts appropriately to reduce apneas and hypopneas and provides suitable levels of positive airway pressure compared to conventional ASV.

Detailed Description
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Adaptive servoventilation (ASV) is a type of non-invasive ventilation which ameliorates central sleep and/or mixed apnea and periodic breathing. Previous studies in the field have shown that treatment of periodic breathing with ASV improves sleep quality and quality of life. In reducing central apneas, ASV reduces overall arousal index, and increases overall slow wave sleep and rapid eye movement (REM) sleep more than oxygen, continuous positive airway pressure or bi-level treatments. ASV can also more effectively reduce central apnea and overall apnea/hypopnea index (AHI) in patients on long-term opiates, and appears to effectively treat Complex Sleep Apnea Syndrome. It is more effective than other forms of non-invasive ventilation for patients with central and/or mixed apnea or periodic breathing, and is better tolerated. This is a prospective, randomised, crossover, observational study. Subjects will spend one night on conventional ASV and one night on modified ASV with full in-lab polysomnography (PSG) during therapy on both nights. Objective and subjective parameters will be recorded and analysed.

Official Title
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Comparison of Modified Adaptive Servoventilation Therapy With Conventional Adaptive Servoventilation Therapy in Patients With Periodic Breathing

Conditions
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Periodic Breathing, Breathing-Related Sleep Disorder

Intervention / Treatment
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* Device: Modified Adaptive Servoventilation Device
* Device: Conventional Adaptive Servoventilation device


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 21+ years old Chronic ResMed ASV therapy patient Current ASV therapy for at least 4 weeks Able to understand fully the study information and participation requirements Provide signed informed consent Exclusion Criteria: Acute cardiac decompensation Acute myocardial infarction within last 3 months Resuscitation within last 3 months Stroke with swallowing disorders or persistent hemiparesis Blood pressure test at end expiratory pressure (EEP) 10cmH2O not passed Untreated restless legs syndrome Alcohol or drug abuse Known cancer Pregnancy Conditions that could interfere with patients participating in and completing the protocol and/or the investigator deems their enrolment unsuitable

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Modified ASV<br>Modified ASV Enhanced ASV algorithm which includes auto-adjusting expiratory pressure. | Device: Modified Adaptive Servoventilation Device<br>* The modified ASV has a greater adaptive response to meet a target ventilation level that is constantly being assessed.<br>* Other names: ASVAuto;|
| Active Comparator: Conventional ASV<br>Conventional ASV This is the current (predicate) ASV algorithm. | Device: Conventional Adaptive Servoventilation device<br>* Pressure support ventilation adapts to meet a target ventilation level that is constantly being assessed.<br>* Other names: ResMed S9 VPAP Adapt;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Apnea/Hypopnea Index (AHI) | Physiological sleep signals including pulse oximetry (SpO2), respiratory effort and nasal flow, will be recorded, analysed and reported in the form of an index per hour of sleep. Apnea-Hypopnea Index is calculated counting all apneas (reduction of respiratory flow by >90% for at least 10 seconds) plus all hypopneas (reduction of respiratory flow by >30% for at least 10 seconds with a 4% SpO2 reduction) divided by hours of sleep. | One night | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygen Desaturation Index (ODI) | Oxygen desaturation index based on SpO2 measurement of number of dips (number of times per hour of sleep that SpO2 Drops by at least 3% below the basic value) will be recorded, analysed and reported. | One night |