CO2 Supplement for Treatment of Acute Mountain Sickness

NCT ID: NCT06393998

Last Updated: 2024-12-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 46 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-06-07
• Study Completion Date: 2024-09-02

Brief Summary

It was reported that up to 76% people who rapidly ascend to the altitude higher than 4500 m without sufficient acclimatization will have AMS which often develops 6-8 hours after reaching at high altitude. AMS could be improved if there is no continuous ascent although central sleep apnea may persist much longer. It has also been well documented that exercise capacity was impaired at high altitude. Oxygen inhalation is the most effective treatment method, but it is impractical for outdoor activities because of the large volume required. There are some drugs such as acetazolamide, and ibuprofen for relieving AMS but side effects and inconsistent treatment effect made them to be difficulty for routine use. It is noted that adding CO2 might be useful for improvement of hypoxia and exercise ability and eliminating CSA. There is no available device which can accurately supply constant CO2 and is functionally free of dead space. We innovated a portable device with a special mask for supplement of CO2 for prophylaxis and treatment of AMS.

Detailed Description

Objective: To determine whether, after rapid ascent to high altitude the device could reduce the incidence and severity of AMS as defined by AMS scores, improve sleep quality and reduce central sleep apnea events.

Methods: A randomized placebo-controlled study will be performed in 36 healthy adults with no history of travelling to high altitude (>1000m) a year before the study. Subjects will be randomly and blindly given either CO2 mixed with air or air alone during daytime and sleep. Blood gases will be measured 30 minutes after inhalation of air or CO2. SaO2, heart rate, and respiratory rate will be recorded every two hours. AMS (Lake Louise Acute Mountain Sickness Score) will be recorded before and after sleep. PSG including diaphragm EMG would be recorded under CO2 or air. Exercise time, ventilation heart rate, respiratory rate, and SaO2 will be recorded and maximal load and peak ventilation will be measured during incremental cycle exercise with inhalation of CO2 or ambient air.

Conditions

Acute Mountain Sickness; High Altitude; Inhalation; Gas

Keywords

Acute mountain sickness; CO2 inhalation; central sleep apnea

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Breathing with CO2 during daytime and night at high altitude

Subjects will sleep and perform exercise tests under inhalation of low concentration of CO2 supplied by a novel device at high altitude.

Group Type: ACTIVE_COMPARATOR

Breathing with CO2 during daytime and night at high altitude

Intervention Type: DEVICE

Subjects wear the mask connecting to low dose CO2 supplied by a novel device during daytime and sleep dependent on the randomization once arriving high altitude.

Breathing with air during daytime and night at high altitude

Subjects will sleep and perform exercise tests under inhalation of air at high altitude.

Group Type: PLACEBO_COMPARATOR

Sleep and doing exercise test under inhalation of air

Intervention Type: DEVICE

Subjects wear the mask connecting to air supplied by the novel device during daytime and sleep dependent on the randomization once arriving high altitude.

Interventions

Breathing with CO2 during daytime and night at high altitude

Subjects wear the mask connecting to low dose CO2 supplied by a novel device during daytime and sleep dependent on the randomization once arriving high altitude.

Intervention Type: DEVICE

Sleep and doing exercise test under inhalation of air

Subjects wear the mask connecting to air supplied by the novel device during daytime and sleep dependent on the randomization once arriving high altitude.

Intervention Type: DEVICE

Other Intervention Names

Sleep and doing exercise test under inhalation of CO2

Eligibility Criteria

Inclusion Criteria

1. BMI less than 25kg/m2

2. normal lung function.

3. Healthy lowlanders (<500m) who have no history to travel to high altitude (>1000m) a year before the study.

Exclusion Criteria

1. insomnia,

2. moderate or severe OSA based on PSG at sea level (AHI> 15 events/hr).

3. visited to an altitude >2500 m in the preceding year.

4. Currently using medicines for diabetes, hypertension et al.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

State Key Laboratory of Respiratory Disease

OTHER

Sponsor Role: lead

Responsible Party

Yuan-Ming Luo

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Yuanming Luo, PhD

Role: PRINCIPAL_INVESTIGATOR

Guangzhou Medical University

Locations

Guangzhou Medical University

Guangzhou, Guangdong, China

Countries

China

Other Identifiers

2020 037

Identifier Type: -

Identifier Source: org_study_id