Randomised controlled trial of average volume-assured pressure support (AVAPS) versus spontaneous/times (ST) mode pressure support ventilation in obesity hypoventilation syndrome

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN63940700

Enrollment

Registered

2008-12-11

Start date

2008-09-01

Completion date

Unknown

Last updated

2015-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obesity hypoventilation syndrome Respiratory Obesity

Interventions

Bi-level positive airway pressure (BiPAP) ventilator will provide both the S/T and AVAPS modes. Total duration of intervention/follow-up: 3 months

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1. Both males and females, aged 18 - 90 years 2. Body mass index (BMI) greater than 40 kg/m^2 3. Daytime partial pressure of carbon dioxide in the arterial blood (PaCO2) greater than 6.5 kPa

Exclusion criteria

Exclusion criteria: Forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) less than 70%

Design outcomes

Primary

Measure	Time frame
Effectiveness of the nocturnal ventilatory support, assessed using the PaCO2 - daytime arterial blood gas (ABG) at baseline and 3 months	—

Secondary

Measure	Time frame
Physiological and clinical benefits in a subgroup of OHS patients with severe obesity and marked daytime hypercapnia, assessed by the following at baseline and 3 months: 1. Partial pressure of oxygen in arterial blood (PaO2), pH, bicarbonate areterial blood gas (HCO3-ABG) 2. Health related quality of life: Severe Respiratory insufficiency Questionnaire, Fatigue Severity Questionnaire 3. Anthropometric data: weight, BMI, neck, hip and waist circumference 4. Activity: Actiwatch® 5. Daytime vigilance: Epworth Sleepiness Scale, Oxford Sleep Resistance (OSLER) test	—

Measure

Time frame

Physiological and clinical benefits in a subgroup of OHS patients with severe obesity and marked daytime hypercapnia, assessed by the following at baseline and 3 months: 1. Partial pressure of oxygen in arterial blood (PaO2), pH, bicarbonate areterial blood gas (HCO3-ABG) 2. Health related quality of life: Severe Respiratory insufficiency Questionnaire, Fatigue Severity Questionnaire 3. Anthropometric data: weight, BMI, neck, hip and waist circumference 4. Activity: Actiwatch® 5. Daytime vigilance: Epworth Sleepiness Scale, Oxford Sleep Resistance (OSLER) test

—

Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026