None listed
Conditions
Brief summary
Subjects who have been using chronic CPAP therapy will be invited to participate in the study. The study will take place after the subjects have been instructed on the details of the trial and have provided informed consent. Subjects are randomised to one of two nights in the sleep laboratory. Under polysomnography and using an auto-titrating CPAP (AutoCPAP) systems, the subjects will be studied either under a sub-therapeutic pressure level for one night of recording (simulating a sub-standard therapy night – encountered by clinical patients), or on the AutoCPAP device in the therapeutic auto-titrating mode (which is also a commonly applied therapeutic device). The study is observational in that the purpose and endpoints are collected as described below, under conditions in the laboratory simulating ‘normal’ clinical occurrences. Sleep and breathing parameters will be collected using standard laboratory methodologies, with the addition of flow measurement from four different sites: nares via a cannula; the CPAP machine flow outlet; the electronic output from the CPAP machine and the standard nasal mask via an oxygen port. Integrity of the flow signal as well as the presence of ‘break-through’ apnea / hypopnea phenomena are evaluated.
Interventions
Subjects will receive an identical two-night titration protocol in random order up to 3 weeks apart. On one night, an auto-adjusting CPAP device will automatically titrate pressure throughout the night within the range of 4cmH2O – 20cmH2O (cmH2O is a centimeter (centimetre) of water used to determine pressures during mechanical ventilation). On the other night, sub-therapeutic pressure will be delivered with the same device set in fixed pressure mode (2/3 of the subject’s currently prescribed CP
Subjects will receive an identical two-night titration protocol in random order up to 3 weeks apart. On one night, an auto-adjusting CPAP device will automatically titrate pressure throughout the night within the range of 4cmH2O – 20cmH2O (cmH2O is a centimeter (centimetre) of water used to determine pressures during mechanical ventilation). On the other night, sub-therapeutic pressure will be delivered with the same device set in fixed pressure mode (2/3 of the subject’s currently prescribed CPAP level (either home fixed CPAP level or the 95th percentile of pressure on current AutoCPAP device)). Subjects will undergo full polysomnography with additional flow measurements from four sites: mask, nares, CPAP machine airflow outlet and the analogue output of the CPAP device.There is no control group in this study. Auto-titrating CPAP therapy is increasingly used to treat sleep disordered breathing, however, the standard care remains fixed pressure CPAP therapy. This is an observational study as both conditions under which data is collected in this study represent actual clinical presentations of clinical patients receiving CPAP therapy.
Sponsors
DiagnoseIT Pty Ltd, Sydney, NSW, Australia
Eligibility
Sex/Gender
All
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
Subjects must satisfy the following inclusion criteria:Previously diagnosed with moderate-severe obstructive sleep apnea (RDI>15)Compliant CPAP use for at least 3 months durationCompliance: CPAP use > 4 hours per night for at least 5 nights per week No significant problems with CPAP therapy such as mask/mouth leak or severe nasal congestion. English speaking.
Exclusion criteria
Other sleep disorders including:PLMD Untreated RLS >10 Central apnoeas/hr on diagnostic sleep studyNeurological disordersPsychiatric disordersSignificant medical complaint including:Severe cardiovascular disease Congestive heart failure Significant lung disease (e.g., chronic obstructive pulmonary disease) Daytime hypoxemia and respiratory failure from any cause Prominent nocturnal desaturation other than from OSA (e.g., obesity hypoventilation syndrome).
Outcome results
None listed