Acute Exposure of Simulated Hypoxia on Heart Rate and Ventilation During Exercise

Acute Exposure to Hypoxia in Precapillary Pulmonary Hypertension: Physiological and Clinical Effects at Rest and During Exercise

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) on heart rate and Ventilation changes under exercise.

Study Overview

• Status: Completed
• Conditions: Pulmonary Hypertension
• Intervention / Treatment: Device: Simulated Altitude: (FiO2: 15.1); Device: Shamed Hypoxia (FiO2: 20.9)

Detailed Description

Low altitude baseline measurements will be performed in Zurich (469m asl) including Echocardiography, right heart catheterization, six-minute walk test (6MWT), pulmonary function test, clinical assessment and blood gas analysis at rest and under exercise.

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.

During the exposure to simulated altitude (FiO2: 15.1%) and shamed altitude of 1 hour each, the participants' heart rate and Ventilation will be compared under exercise.

• Study Type: Interventional
• Enrollment (Actual): 28
• 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
• PH diagnosed according to internation Guidelines: mean pulmonary artery pressure (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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Order A; The participants will be consecutively exposed to shamed hypoxia (FiO2: 20.9%) equivalent to sea level and to simulated altitude (FiO2: 15.1%) equivalent to 2500m above sea level administered by an altitude simulator ("Altitrainer, SMTEC") with a facemask.	Device: Simulated Altitude: (FiO2: 15.1); Inhalation of deoxygenated air through an altitude simulator ("Altitrainer") for approximately 1 hour given by a facemask.; Device: Shamed Hypoxia (FiO2: 20.9); Inhalation of unmodified air through an altitude simulator ("Altitrainer") for approximately 1 hour given by a facemask.
Experimental: Order B; The participants will be consecutively exposed to hypoxia (FiO2: 15,1%) equivalent to 2500m above sea level and to shamed hypoxia (FiO2: 20.9%) equivalent to sea level administered by an altitude simulated ("Altitrainer, SMTEC") with a facemask.	Device: Simulated Altitude: (FiO2: 15.1); Inhalation of deoxygenated air through an altitude simulator ("Altitrainer") for approximately 1 hour given by a facemask.; Device: Shamed Hypoxia (FiO2: 20.9); Inhalation of unmodified air through an altitude simulator ("Altitrainer") for approximately 1 hour given by a facemask.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
heart rate under exercise	Change in heart rate under exercise during the exposure to simulated altitude (FiO2: 15,1%) and normoxia.	1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ventilation under exercise	Change in Ventilation under exercise during the exposure to simulated altitude	1 hour

Collaborators and Investigators

• Sponsor: University of Zurich

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2018
• Primary Completion (Actual): April 1, 2019
• Study Completion (Actual): April 1, 2019

Study Registration Dates

• First Submitted: July 9, 2018
• First Submitted That Met QC Criteria: July 18, 2018
• First Posted (Actual): July 19, 2018

Study Record Updates

• Last Update Posted (Actual): January 7, 2020
• Last Update Submitted That Met QC Criteria: January 6, 2020
• Last Verified: January 1, 2020

More Information

Terms related to this study

• Keywords: exercise; ventilation; heart rate; Simulated altitude
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Respiratory Tract Diseases; Lung Diseases; Signs and Symptoms, Respiratory; Hypertension; Hypertension, Pulmonary; Hypoxia
• Other Study ID Numbers: 2018-00455_A7

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