Related Experiment Video

Updated: Jan 12, 2026

Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea

Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea

Published on: December 6, 2016

A Pilot Randomised Non-Inferiority Trial of Auto-Titrating Versus Fixed Continuous Positive Airway Pressure for

Yizhong Zheng^1,2,3, Amanda Piper⁴, Keith Wong^1,4,5

¹Woolcock Institute of Medical Research, Sydney, Australia.

Respirology (Carlton, Vic.)

|November 2, 2025

Abstract

Background And Objective:

Fixed CPAP (fCPAP) is the preferred first-line ventilatory therapy in patients with obesity hypoventilation syndrome with severe obstructive sleep apnoea (OHS + sOSA). Auto-titrating CPAP (APAP) is not recommended but has not been systematically evaluated in this population. Our pilot study aimed to provide feasibility data for a larger comparative effectiveness trial to determine whether APAP is non-inferior to fCPAP for improving hypercapnic respiratory failure.

Methods:

Participants with OHS + sOSA were randomised to either APAP or fCPAP for 3 months. The primary outcome was the change in PaCO₂. Secondary outcomes included changes in quality of life and cardiovascular biomarkers. A sample size of 82 was needed to demonstrate non-inferiority of APAP compared to fCPAP (assuming a non-inferiority margin of -2.5 mmHg). To assess feasibility we aimed to recruit up to 44 participants in this pilot trial.

Results:

Twenty-eight of 84 screened participants were randomised (Mean ± SD: Age 55 ± 12.5 years, BMI 54 ± 9.9 kg m^-2, PaCO₂ 49 ± 2.6 mmHg, AHI 88 ± 31 events/h) to APAP (n = 15) or fCPAP (n = 13). Mean adherence exceeded 4 h in both groups; however 25% of randomised participants did not complete the trial. Both treatments reduced PaCO₂ (fCPAP: -5.7 ± 1.6 mmHg, APAP: -4.1 ± 2.8 mmHg). Test of non-inferiority for APAP versus fCPAP was inconclusive (mean ΔPaCO₂ difference = -1.7 mmHg (95% CI -5.0 to 1.6 mmHg)). Adherence and sleep quality improvements favoured fCPAP, while other outcomes were comparable.

Conclusion:

The pilot study highlighted important challenges with recruitment and retention. While the study is not powered to confirm the non-inferiority of APAP, some outcomes appeared to favour fCPAP and APAP use in OHS + sOSA should be approached cautiously. A larger study with protocol modifications is required to confirm these preliminary findings.

Trial Registration:

ACTRN12618000379213. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374259. Assessing the Efficacy of Auto-titrating versus Fixed Continuous Positive Airway Pressure in Obesity Hypoventilation Syndrome.

Keywords:

cardiovascular disease hypercapnic respiratory failure obesity positive airway pressure therapy quality of life sleepiness

More Related Videos

Author Spotlight: Traditional Chinese Medicine for Sleep Disorders in Acute COPD — A Safe, Cost-Effective Approach

Author Spotlight: Traditional Chinese Medicine for Sleep Disorders in Acute COPD — A Safe, Cost-Effective Approach

Published on: October 18, 2024

Related Concept Videos

Mechanical Ventilation III: Noninvasive Ventilation

Mechanical Ventilation III: Noninvasive Ventilation

Noninvasive positive-pressure ventilation (NIPPV), continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP) are essential methods in respiratory care. These ventilation techniques offer unique benefits for patients with various respiratory conditions, providing adequate support without requiring intubation. Let's explore how each method is crucial in improving patient outcomes and enhancing respiratory therapy.
Noninvasive Positive-Pressure Ventilation...

Sleep Apnea

Sleep Apnea

Sleep apnea is a condition where breathing stops intermittently during sleep, often leading to significant health issues. Each episode can last from 10 to 20 seconds or more and is frequently accompanied by a brief arousal from sleep. This disturbance, largely unnoticed by the individual, can lead to severe daytime fatigue. Commonly, individuals seek help after being informed by their partners about loud snoring and noticeable breathing pauses during sleep.
The condition is more prevalent among...

Mechanical Ventilation I: Indication and Settings

Mechanical Ventilation I: Indication and Settings

Mechanical ventilation is a life-saving technique for managing acute respiratory failure and other respiratory complications. The process involves using a machine known as a ventilator to supply oxygen to the lungs and assist in removing carbon dioxide. It serves as a bridge to long-term mechanical ventilation or a temporary measure until ventilatory support is discontinued. The ventilator can maintain this function for a prolonged period, providing critical support for patients until they can...

Treatment for Pulmonary Arterial Hypertension: Oxygen Therapy for Respiratory Failure

Treatment for Pulmonary Arterial Hypertension: Oxygen Therapy for Respiratory Failure

Oxygen therapy has emerged as a significant tool in enhancing the quality of life for patients suffering from pulmonary arterial hypertension (PAH). While this therapy has principally been studied on patients with significant hypoxemia, this therapeutic approach helps prevent potential organ damage and can be administered in the comfort of one's home.
Oxygen therapy is vital in increasing and maintaining blood oxygen levels in PAH patients. As a result, it aids in reducing fatigue,...

Hyperpnea and Hyperventilation

Hyperpnea and Hyperventilation

Hyperventilation refers to a higher-than-normal rate and depth of breathing, often associated with anxiety attacks. This excessive breathing surpasses the body's need to expel CO2, leading to a condition known as hypocapnia - an unusually low level of carbon dioxide in the blood. Hypocapnia can constrict cerebral blood vessels, reducing blood flow to the brain, which may result in dizziness or fainting. Early signs include tingling and muscle spasms in the hands and face, caused by falling...

Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies

Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies

Assessing and diagnosing Chronic Obstructive Pulmonary Disease (COPD) involves a detailed approach that includes a comprehensive review of medical history, physical examination, and a variety of diagnostic tests. This thorough evaluation is essential to ensure an accurate diagnosis and guide effective management strategies.
Medical History

Articles linked to this work by shared authors, journal, and citation graph.

A Double-Blind Randomised Controlled Crossover Trial of the Effect of Blue-Enriched Ambient Light on Sleep in Older Adults With Sleep Disturbance: The CleverLights Study.

Journal of sleep research·2026

Nocturia as a clinical marker of cardiovascular risk in obstructive sleep apnoea.

Sleep medicine·2026

Does Hypoxic Burden Better Explain Sex Differences in Functional Impairments Than Apnoea-Hypopnoea Index in Obstructive Sleep Apnoea?

Journal of sleep research·2026

Targeting Orexin 2 Receptors in Idiopathic Hypersomnia and Narcolepsy: A Randomised Phase 1b Proof-Of-Concept Study of Alixorexton.

Journal of sleep research·2026

The Role of Pharmacotherapy for Excessive Daytime Sleepiness in OSA: A Changing Landscape?

CHEST pulmonary·2026

Prognostic Value of Interim PSMA-PET Total Tumor Volume for Overall Survival Within ENZA-p, A Randomized Phase 2 Trial of Enzalutamide Versus Enzalutamide Plus [177Lu] Lu-PSMA-617 (ANZUP1901).

European urology·2026

See all related articles