Effect of Oxygen Therapy for Patients With Precapillary Pulmonary Hypertension Who Experience an Altitude Related Adverse Health Effect (ARAHE) During 30h Exposure to 2500m

The Impact of Hypoxia on Patients With Precapillary Pulmonary Hypertension and Treatment of Adverse Effects

To study whether oxygen therapy titrated to maintain oxygenation (SpO2) > 90% at 2500m would resolve altitude-related adverse health effects, symptoms and impaired exercise during 30h exposure to high altitude.

Study Overview

• Status: Completed
• Conditions: Oxygen Therapy; High Altitude Pulmonary Hypertension
• Intervention / Treatment: Other: Oxygen Therapy

Detailed Description

Patients with pulmonary hypertension who reveal an altitude-related adverse health effects at 2500m will be given oxygen therapy by nasal cannula titrated to maintain the oxygen saturation above 90%. The study will investigate, whether this measure will restore altitude-induced impairment to baseline levels at low altitude.

• Study Type: Interventional
• Enrollment (Actual): 9
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich, Switzerland, 8091
    • Respiratory Clinic, University Hospital of Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Informed consent as documented by signature
• PH class I (PAH) or IV (CTEPH) diagnosed according to guidelines: mean pulmonary artery pressure >20 mmHg, pulmonary vascular resistance ≥3 wood units, pulmonary arterial wedge pressure ≤15 mmHg during baseline measures at the diagnostic right-heart catheterization

Exclusion Criteria:

• resting partial pressure of oxygen <8 kilopascal at Zurich at 490 m low altitude
• exposure to an altitude >1000 m for ≥3 nights during the last 2 weeks before the study
• inability to follow the procedures of the study
• other clinically significant concomitant end-stage disease (e.g., renal failure, hepatic dysfunction)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Oxygen Therapy; Oxygen Therapy in patients developing an altitude related adverse health effect (ARAHE) during 30h exposure to 2500m of high altitude	Other: Oxygen Therapy; Oxygen Therapy in patients developing an altitude related adverse health effect (ARAHE) during 30h exposure to 2500m of high altitude

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Recovery from ARAHE	Proportion of patients with precapillary pulmonary hypertension experiencing an ARAHE at 2500 m of high altitude and receiving oxygen therapy titrated to achieve SpO2 ≥ 90% who recover from ARAHE, have improved symptoms and achieve constant work-rate exercise time within a minimal important difference as defined for patients with respiratory disease within 1.75 min of baseline value at 490 m; time frame within 6 h after initiation of oxygen therapy.	30 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Constant work-rate exercise time	Difference with oxygen therapy at high altitude vs. low altitude in constant work-rate exercise time cycle exercise test at 75% Wmax at low altitude	30 hours
Maximum work-rate in incremental ramp cycle exercise tests	Difference with oxygen therapy at high altitude vs. low altitude in maximal exercise capacity during a incremental ramp cycle exercise test	30 hours
Hemodynamics	Difference with oxygen therapy at high altitude vs. low altitude in hemodynamics assessed by echocardiography at rest including pulmonary artery pressure, cardiac output, pulmonary vascular resistance and right heart function assessed as tricuspid plane systolic excursion and fractional area change.	30 hours
Borg dyspnoea scale	Difference with oxygen therapy at high altitude vs. low altitude baseline in post-exercise Borg dyspnoea scale going from 1-10 scores with higher values meaning worse dyspnea	30 hours
Visual Analogue Scale	Difference with oxygen therapy at high altitude vs. low altitude baseline in symptoms assessed by the Visual Analogue Scale for dyspnoea, a 10cm line from left to right where patients have to add a cross-line with higher values meaning better feeling.	30 hours
Cognitive testing	Difference with oxygen therapy at high altitude vs. low altitude baseline in cognitive function tests	30 hours
sit-to-stand test	Difference with oxygen therapy at high altitude vs. low altitude baseline in sit-to-stand test	30 hours
Sleep disordered breathing	Difference with oxygen therapy at high altitude vs. low altitude in sleep disordered breathing	30 hours
6 minute walk test	Difference with oxygen therapy at high altitude vs. low altitude in 6 minute walk test	30 hours
Acute Mountain Sickness Score	Difference with oxygen therapy at high altitude vs. low altitude baseline in symptoms assessed by the Lake Louise acute mountain sickness score going from 0-12 points with mild AMS as 3-5 points, moderate AMS as 6-9 points, and severe AMS as 10-12 points.	30 hours

Collaborators and Investigators

• Sponsor: University of Zurich

Study record dates

Study Major Dates

• Study Start (Actual): October 18, 2021
• Primary Completion (Actual): April 15, 2022
• Study Completion (Actual): April 15, 2022

Study Registration Dates

• First Submitted: October 14, 2021
• First Submitted That Met QC Criteria: October 27, 2021
• First Posted (Actual): November 8, 2021

Study Record Updates

• Last Update Posted (Actual): May 11, 2022
• Last Update Submitted That Met QC Criteria: May 10, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Respiratory Tract Diseases; Lung Diseases; Hypertension; Hypertension, Pulmonary
• Other Study ID Numbers: OVERALP II B

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No