Effect of Short-term Simulated Altitude Exposure on Cardiopulmonary Functional Capacity

Not Applicable

Terminated

• Conditions: Hypoxia
• Interventions: Other: Hypoxia; Other: Normoxia

• Registration Number: NCT02523716
• Lead Sponsor: University of Limerick

Brief Summary

To determine if exposure of older volunteers, age 50-70y, who are healthy, but not physically active, to 7 days of mild hypoxia (15% oxygen, equivalent 2440m) will improve cardiopulmonary functional capacity.

Detailed Description

Background There is an urgent need to reduce morbidity and mortality following major surgery. Bodily demands for oxygen increase after major surgery, and postoperative outcomes can be predicted by quantifying the body's ability to meet increased mitochondrial demand for oxygen using cardiopulmonary exercise testing (CPET).

Design This is a preliminary, physiological study to establish the baseline relationship between mild hypoxia exposure and cardiopulmonary function. This study will begin to examine the feasibility and potential for achieving risk modification through low-oxygen (hypoxic) conditioning, in which a safe and convenient "dose" of mild hypoxia is used to improve CPET derived variables that predict mortality following surgery.

The study will use a randomised, double blind, sham-controlled, crossover design. After a baseline CPET test, participants will be exposed to 7 days of either mildly hypoxic or normoxic air. A follow up CPET test will then be used to determine if cardiopulmonary functional capacity increased after exposure. After a two week washout period, participants will return for a second 7-day session where the alternate exposure will be given. A final follow-up CPET test will then be performed.

Study Timeline

• Study Start: 2015-05
• Study First Submitted: 2015-06-02
• Study First Submitted QC: 2015-08-13
• Study First Posted: 2015-08-14
• Primary Completion: 2015-09-30
• Study Completion: 2015-12-30
• Status Verified: 2021-04
• Last Update Submitted: 2023-12-05
• Last Update Posted: 2023-12-06

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 8

Inclusion Criteria

• Healthy male and female individuals aged 50-70 years with sedentary lifestyles.

Exclusion Criteria

• Known intolerance to altitude identified by the participant's clinical examination, history and pre-altitude screening completed by the research clinician.
• Non-availability and/or suitability to complete the required residential period within the altitude centre.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Hypoxia	Hypoxia	Mild hypoxia of 15% oxygen, equivalent altitude of 2440m over a period of 7 days
Normoxia	Normoxia	Exposure to normal, sea-level air

Primary Outcome Measures

Name	Time	Method
Change in Cardio pulmonary functional variables	Change in Cardio pulmonary functional variables between day 0 and day 7 in each arm of the study.	Assess cardio pulmonary functional variables using cardio pulmonary exercise testing (CPET) prior and following participants completing each arm of the study