Acute Exposure to Simulated Hypoxia on Exercise Capacity

NCT ID: NCT03592927

Last Updated: 2019-08-16

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 28 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-08-01
• Study Completion Date: 2019-04-01

Brief Summary

Randomized crossover trial in patients with Pulmonary Hypertension (PAH, CTEPH) to assess the acute response to simulated altitude (FiO2:15.1, equivalent to 2500m above sea level) in constant loaded exercise capacity.

Detailed Description

Low altitude baseline measurements will be performed in Zurich (460m asl) including Echocardiography, Right heart catheterization, six-minute walk test (6MWT), pulmonary function test, clinical assessment and blood gas Analysis.

Randomly assigned to the order of testing, the participants will be tested under simulated altitude (FiO2: 15.1% with the "AMC Altitrainer") and shamed altitude with the same device.

Towards the end of the exposure after approximately 1h, the participants will perform a constant loaded exercise test on an Ergometer with a calculated resistance of their 60% max. workload.

The patients will be encouraged to perform this test up to their physical exhaustion.

Conditions

Pulmonary Hypertension

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: PREVENTION
• Blinding Strategy: SINGLE

Study Groups

Order A

The participants will be exposed to shamed hypoxia (FiO2: 20.9% equivalent to sea level and consecutively to simulated altitude (FiO2: 15.1% equivalent to 2500m above sea level) administered by an altitude Simulator ("Altitrainer", SMTEC), simulated altitude (FiO2: 15.1%), with a facemask.

Group Type: EXPERIMENTAL

Simulated Altitude (FiO2: 15.1%)

Intervention Type: DEVICE

Inhalation of deoxygenated air through a altitude simulator ("Altitrainer"), for approx. 1 hour. given by a facemask.

Shamed Hypoxia (FiO2: 20.9)

Intervention Type: DEVICE

Inhalation of unmodified air through an altitude Simulator ("Altitrainer") for approximately 1 hour given by a facemask

Order B

The participant will be exposed to hypoxia (FiO2, 15.1% equivalent to 2500m above sea level), simulated altitude (FiO2: 15.1%), and consecutively to shamed hypoxia (FiO2, 20.9%) administered by an altitude simulator ("Altitrainer", SMTEC) with a facemask.

Group Type: EXPERIMENTAL

Simulated Altitude (FiO2: 15.1%)

Intervention Type: DEVICE

Inhalation of deoxygenated air through a altitude simulator ("Altitrainer"), for approx. 1 hour. given by a facemask.

Shamed Hypoxia (FiO2: 20.9)

Intervention Type: DEVICE

Inhalation of unmodified air through an altitude Simulator ("Altitrainer") for approximately 1 hour given by a facemask

Interventions

Simulated Altitude (FiO2: 15.1%)

Inhalation of deoxygenated air through a altitude simulator ("Altitrainer"), for approx. 1 hour. given by a facemask.

Intervention Type: DEVICE

Shamed Hypoxia (FiO2: 20.9)

Inhalation of unmodified air through an altitude Simulator ("Altitrainer") for approximately 1 hour given by a facemask

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Informed consent
• PH diagnosed according to internation Guidelines: mean pulmonary artery presssure (mPAP) ≥ 25 mmHg along with a pulmonary artery wedge pressure (PAWP) ≤15 mmHg during right heart catheterization at the time of initial diagnosis
• PH class 1 (PAH) or 4 (CTEPH)
• Stable condition, on the same medication for > 4 weeks
• Patient live permanently at an altitude < 1000m asl.

Exclusion Criteria

• Resting partial Oxygen pressure (PaO2) ≤7.3 kiloPascal (kPA) corresponding to the requirement of long-term oxygen therapy > 16hour daily (nocturnal oxygen therapy alone is allowed)
• Severe daytime hypercapnia (pCO2 > 6.5 kPa)
• Susceptibility to high altitude related diseases (AMS, High Altitude Pulmonary edema (HAPE), etc.) based on previous experienced discomfort at altitudes.
• Exposure to an altitude >1500m for ≥3 nights during the last 4 weeks before the study participation
• Residence > 1000m above sea level
• Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, neurological or orthopedic problems with walking disability
• Women who are pregnant or breast feeding

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Zurich

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Silvia Ulrich, Prof.

Role: PRINCIPAL_INVESTIGATOR

University of Zurich

Locations

Respiratory Clinic, University Hospital of Zurich

Zurich, , Switzerland

Countries

Switzerland

References

Schneider SR, Lichtblau M, Furian M, Mayer LC, Berlier C, Muller J, Saxer S, Schwarz EI, Bloch KE, Ulrich S. Cardiorespiratory Adaptation to Short-Term Exposure to Altitude vs. Normobaric Hypoxia in Patients with Pulmonary Hypertension. J Clin Med. 2022 May 14;11(10):2769. doi: 10.3390/jcm11102769.

Reference Type: DERIVED

PMID: 35628896 (View on PubMed)

Schneider SR, Mayer LC, Lichtblau M, Berlier C, Schwarz EI, Saxer S, Furian M, Bloch KE, Ulrich S. Effect of Normobaric Hypoxia on Exercise Performance in Pulmonary Hypertension: Randomized Trial. Chest. 2021 Feb;159(2):757-771. doi: 10.1016/j.chest.2020.09.004. Epub 2020 Sep 9.

Reference Type: DERIVED

PMID: 32918899 (View on PubMed)

Other Identifiers

2018-00455_A1

Identifier Type: -

Identifier Source: org_study_id