Acute Exposure to High Altitude on Blood and Tissue Oxygenation (ABGA, NIRS)

University of Zurich (UZH)

Status: Completed

Conditions: Pulmonary Hypertension

Treatments: Other: Low altitude: 470m above sea level; Other: Säntis; 2500m above sea level

Study type: Interventional

Funder types: Other

Identifiers

NCT03600415

2018-00455_B5

Details and patient eligibility

About

Randomized crossover Trial in patients with Pulmonary Hypertension (PAH, CTEPH) to assess the acute response to High Altitude (2500m above sea level) on blood and tissue oxygenation (ABGA, NIRS).

Full description

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

Randomly assigned to the order of testing, the participants will be tested in Low Altitude (Zurich, 470m) and at High Altitude (2500m).

At rest and under exercise data from ABGA and NIRS will be compared at low altitude and High Altitude.

Enrollment: 28 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Informed consent
• PH diagnosed according to internation Guidelines: mPAP ≥ 25 mmHg along with a 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 PaO2 ≤7.3 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, 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

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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28 participants in 2 patient groups

Order A

Experimental group

Description:

The participants will be tested in Zurich (Low altitude: 470m above sea level) and consecutively at High Altitude(Säntis; 2500m above sea Level)

Treatment:

Other: Säntis; 2500m above sea level

Other: Low altitude: 470m above sea level

Order B

Experimental group

Description:

The participants will be tested at High Altitude (Säntis; 2500m above sea level) and consecutively in Zurich (Low altitude; 470m above sea level).

Treatment:

Other: Säntis; 2500m above sea level

Other: Low altitude: 470m above sea level