Carbon Dioxide Rebreathing During Exercise Assisted by Non-invasive Ventilation

NCT ID: NCT02655484

Last Updated: 2016-07-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 18 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-01-31
• Study Completion Date: 2016-05-31

Brief Summary

The purpose of this study was to evaluate whether CO2 rebreathing occurs in healthy subjects or patients with COPD ventilated during exercise assisted by the single-limb circuit with a plateau exhalation valve at a given inspiratory positive airway pressure and a minimal level of expiratory positive airway pressure (EPAP) and whether there is a potential threshold for predicting CO2 rebreathing.

Detailed Description

Non-invasive ventilation circuit consists of single-limb tubing for inspiration and expiration, including a plateau exhalation valve. As exhaled gases was vented out the plateau exhalation valve at a constant rate, during exercise, with the increase of exhalation flow, single-limb circuit with a plateau exhalation valve might cause carbon dioxide(CO2) rebreathing. Therefore, our aim in the present study was to evaluate whether CO2 rebreathing occurs in COPD patients ventilated during exercise assisted by the single-limb circuit with a plateau exhalation valve and estimate a potential threshold for predicting CO2 rebreathing.

Conditions

Pulmonary Disease, Chronic Obstructive

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Blinding Strategy: NONE

Study Groups

COPD patients

Oxygen was delivered to the face mask by a tube at a constant rate (5L/min) to keep the fingertip oxygen saturation at 90% or above. Ventilatory assistance was delivered using a BiPAP® Vision® ventilator (Respironics, Murrysville, Pennsylvania, USA) in BiPAP mode applied via a tightly fitting full face mask (Curative, Suzhou, China). A symptom-limited cycle exercise test was performed while assisted by non-invasive ventilation (NIV). All measurements were recorded at inspiratory pressure of 14 cmH2O, expiratory pressure of 4 cmH2O during rest and exercise. Breathing pattern, mean exhalation flow, mean plateau exhalation valve flow, the mean inspiratory fraction of CO2 (tidal FiCO2) reinsufflated from the circuit between the mask and the exhalation valve was measured for each breath.

Group Type: OTHER

BiPAP® Vision® ventilator（"Ventilator", "Philips Respironics™ BiPAP® Vision®" ）

Intervention Type: DEVICE

See details from arm descriptions.

Interventions

BiPAP® Vision® ventilator（"Ventilator", "Philips Respironics™ BiPAP® Vision®" ）

See details from arm descriptions.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• presented clinically stable (no exacerbation in the 4 weeks prior to study participation or with no change in medications);
• physician diagnosed COPD, forced expiratory volume in 1s (FEV1) < 50% predicted;
• dyspnea as a main symptom that limited daily activities.

Exclusion Criteria

• subjects with obvious pulmonary bullae demonstrated by chest CT scan or X-ray;
• examination or facial trauma/malformation, recent facial, upper airway or upper gastrointestinal tract surgery, that would preclude receiving NIV therapy;
• a history of coronary artery disease or cardiac arrhythmias or potential electrocardiographic alterations;
• a history of uncontrolled hypertension, or other respiratory diseases;
• oxygen saturation(SpO2) < 88% at rest with a fraction of inspired oxygen (FiO2) ≥ 0.5;
• patients with musculoskeletal or neurological disorders;
• or failure to comply with the research protocol.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Guangzhou Institute of Respiratory Disease

OTHER

Sponsor Role: lead

Responsible Party

RongChang Chen

director of Guangzhou Institute of Respiratory Disease

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Rongchang Chen, MD

Role: PRINCIPAL_INVESTIGATOR

Guangzhou Institute of Respiratory Disease

Locations

State Key Laboratory of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University

Guangzhou, Guangdong, China

Countries

China

Other Identifiers

2009CB522112

Identifier Type: -

Identifier Source: org_study_id