Clinical trial NCT06390631: Effect of CPAP on Respiratory Load in COPD
Official title: Effect of CPAP on Respiratory Load and Lung Volume in Stable COPD
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Chronic Obstructive Pulmonary Disease
Keywords: COPD
CPAP
Diaphragm EMG
Lead sponsor: State Key Laboratory of Respiratory Disease
Sponsor class: OTHER
First posted: 2024-04-30
Enrollment: 19
Sex: ALL
Minimum age (years): 40
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: CPAP treatment
Primary purpose: TREATMENT

Brief summary: Both intrinsic positive end expiratory pressure (PEEPi) and dynamic hyperinflation are considered as inspiratory loads which increase work of breathing in patients with COPD. The application of extrinsic positive end expiratory pressure (PEEPe) supplied by CPAP has been claimed to reduce inspiratory load based on change in esophageal pressure which could be significantly affected by change in lung volume and airflow. The investigator hypothesized that CPAP could increase respiratory load because it increases lung volume.

Detailed description: Objective: To assess the effect of CPAP on respiratory load and lung volume in stable COPD. Methods: Patients with COPD were recruited to breath under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O). Diaphragm EMG, esophageal pressure (Pes) and transdiaphragmatic pressure (Pdi) were recorded using balloon esophageal electrode catheter (Yinghui, Guangzhou, China). End inspiratory lung volume (EILV) was measured directly from a pneumotachograph combined with a three way valve under the different CPAP levels. Sensation of breathing difficulty was also assessed. In an additional study, the effect of airflow on pressure was investigated by a physical mode.

Eligibility criteria: Inclusion Criteria:

1. Willing to participate after informed consent
2. Males and females, any race and aged 40-80 years
3. GOLD II-IV COPD (post-bronchodilator FEV1 \< 80 % of the predicted normal, and a post-bronchodilator FEV1/FVC \< 0.70)

Exclusion Criteria:

1. Patients recovering from acute exacerbation less than 4 weeks.
2. Patients with concomitant pulmonary disease (e.g. lung fibrosis, interstitial lung disorder).

Primary outcomes:
measure: Diaphragm EMG
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Lung volume
timeFrame: 1-3 minutes after each CPAP level (0, 4, 6, 8 and 10 cm H2O)
measure: Intrinsic positive end expiratory pressure (PEEPi)
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Inspiratory pressure
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Inspiratory work
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Sensation of breathing effort
timeFrame: 5 minutes after each CPAP level (0, 4, 6, 8 and 10 cm H2O)
Secondary outcomes:
measure: Respiratory rate (RR)
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Tidal volume (Vt)
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Minute ventilation (VE)
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Peak inspiratory flow rate
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Expiratory muscle EMG
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
measure: Expiratory pressure
timeFrame: Around 5 minutes signals under the atmosphere pressure and different levels of CPAP (4, 6, 8 and 10 cm H2O) were recorded.
Other outcomes:
Locations:
city: Guangzhou
country: China
facility: Guangzhou Medical University
state: Guangdong
Study officials:
affiliation: Guangzhou Medical University
name: Yuanming Luo, PHD
role: PRINCIPAL_INVESTIGATOR
References: