Hyperoxia During Outpatient Pulmonary Rehabilitation in Chronic Lung Disease - Does it Matter?

Chronic obstructive pulmonary disease (COPD) is a global burden. Treatment options have improved in recent years, pulmonary rehabilitation plays a key role. Oxygen therapy is recommended in patients with a low saturation at rest, but no clear guidance is given for patients who desaturate during exercise. The effect of ambulatory oxygen during exercise is not yet completely understood, especially in those patients with exercise-induced desaturation.

Aim: Evaluate the effect of supplemental oxygen therapy during a 3-months long ambulatory pulmonary rehabilitation program on exercise endurance. Patients will either receive supplemental oxygen therapy or room air during exercise training.

Methods: A total of 32 patients with a confirmed diagnosis of COPD undergoing pulmonary rehabilitation will be included (male and female : aged ≥ 18 years; stable condition > 3 weeks (e.g. no exacerbations); resting oxygen saturation (SpO2) ≥ 88% and exercise induced hypoxemia defined by a fall in SpO2 by ≥ 4% and/ or below 90% during a 6-minute walking test). 3-months comprehensive PR for both intervention and control group including: education and awareness, instruction on inhalation therapies, smoking cessation counselling, respiratory and skeletal muscle training in groups, guided walks / cycle ergometer training. The intervention group will be trained using SSOT and the control group will receive sham air (ambient air). Patients and assessors will be blinded. Between group difference in cycling constant work rate exercise test (CWRET) time from baseline to 3 months SSOT (5l/min) vs ambient air will be the primary outcome of this study.

Data will be summarized by means (SD) and medians (quartiles) for normal and non-normal distributions. Effects of treatment will be evaluated by mean differences with 95% confidence intervals, T-tests or Wilcoxon matched pair tests as appropriate. A p-value threshold of <0.05 or a confidence interval not including zero will be considered as statistically significant. Analyses will be performed according to the intention to treat principle.

Study Overview

• Status: Recruiting
• Conditions: Chronic Obstructive Pulmonary Disease (COPD)
• Intervention / Treatment: Other: Room Air (placebo); Other: Oxygen

• Study Type: Interventional
• Enrollment (Estimated): 32
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Stéphanie Saxer, PHD; Phone Number: +41 58 257 12 97; Email: stephanie.saxer@ost.ch
• Study Contact Backup: Name: Spencer Rezek; Phone Number: +41522663867; Email: spencer.rezek@ost.ch

Study Locations

• Switzerland
  • Zürich
    • Winterthur, Zürich, Switzerland, 8400
      • Recruiting
      • Kantonsspital Winterthur
      • Contact: Spencer Rezek, PhD cand.; Phone Number: +41754383867; Email: spencer.rezek@ksw.ch

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• We will include male and female with a confirmed diagnosis of COPD (post-bronchodilator forced expiratory volume in one second (FEV1) / forced vital capacity (FVC) ratio of <0.7; a greater than 10 pack-year smoking history)
• undergoing pulmonary rehabilitation
• aged ≥ 18 years
• stable condition > 3 weeks (e.g. no exacerbations)
• resting oxygen saturation (SpO2) ≥ 88%
• exercise induced hypoxemia defined by a fall in SpO2 by ≥ 4% and/ or below 90% during a 6MWT
• informed consent as documented by signature.

Exclusion Criteria:

• Severe daytime resting hypoxemia (SpO2 < 88% )
• long-term oxygen therapy, unstable condition requiring adaptation of pharmacologic and other treatment modalities or requirement of intensive care or relevant severe concomitant disease
• inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, neurological or orthopedic problems with walking disability or inability to ride a bicycle
• women who are pregnant or breast feeding; enrolment in another clinical trial with active treatment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Endurance training with 5l/ min room air applied via nasal cannula.; Endurance training with 5l/ min room air applied via nasal cannula with an Everflo oxygen concentrator.	Other: Room Air (placebo); Room air (5l/min) will be applied with an oxygen concentrator via nasal cannula during endurance training.
Experimental: Endurance training with 5l/ min Oxygen Therapy applied via nasal cannula.; Endurance training with 5l/ min Oxygen Therapy applied via nasal cannula with an Everflo oxygen concentrator..	Other: Oxygen; Standard supplemental Oxygen therapy (5l/min) will be applied with an oxygen concentrator via nasal cannula during endurance training.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Constant Work Rate Exercise Test Endurance time	Constant Work Rate Exercise Test Endurance time measured with Constant Work Rate Exercise Test (CWRET) (75% of the maximal work rate from the maximal ramp exercise test)	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
6 minute walk test (6MWT)	6 minute walk distance (6MWD), SpO2 and heart rate at the end of the 6 minute walk test (6MWT) from baseline to 3 months at SSOT vs ambient air	3 months
SpO2	SpO2 by finger pulse oximetry, brain and muscle tissue oxygenation by NIRS at rest and end-exercise CWRET from baseline to 3 months at SSOT vs ambient air	3 months
Heart rate	Heart rate at rest and end-exercise CWRET from baseline to 3 months at SSOT vs ambient air	3 months
Borg scale	Borg scale (Dyspnoea and fatigue) at rest and end-exercise CWRET from baseline to 3 months at SSOT vs ambient air. Measure of perceived exertion from 1-10, ranges from 1 (very light exertion) to 10 (maximum exertion).	3 months
Constant Work Rate Exercise Test Endurance time	Constant Work Rate Exercise Test Endurance time measured with Constant Work Rate Exercise Test (CWRET) (75% of the maximal work rate from the maximal ramp exercise test)	6 months

Collaborators and Investigators

• Sponsor: Eastern Switzerland University of Applied Sciences
• Collaborators: University Hospital, Zürich; Kantonsspital Winterthur KSW
• Investigators: Principal Investigator: Silvia Ulrich, Prof., University of Zurich

Study record dates

Study Major Dates

• Study Start (Actual): January 6, 2025
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): August 1, 2027

Study Registration Dates

• First Submitted: December 16, 2024
• First Submitted That Met QC Criteria: January 13, 2025
• First Posted (Actual): January 15, 2025

Study Record Updates

• Last Update Posted (Actual): August 7, 2025
• Last Update Submitted That Met QC Criteria: August 4, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: COPD; pulmonary rehabilitation; hyperoxia; oxygen therapy; exercise medicine
• Additional Relevant MeSH Terms: Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Diseases; Signs and Symptoms, Respiratory; Lung Diseases; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive; Hyperoxia
• Other Study ID Numbers: outRehaExO2

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be made available upon request through the corresponding author

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No