Skip to main content
OpenTrials
Completed

NCT Number: NCT06393998

CO2 Supplement for Treatment of Acute Mountain Sickness

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.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Acute Mountain Sickness Altitude Sickness Apnea Carbohydrate Metabolism, Inborn Errors Congenital, Hereditary, and Neonatal Diseases and Abnormalities Connective Tissue Diseases Dyssomnias Genetic Diseases, Inborn High Altitude Inhalation; Gas Lysosomal Storage Diseases Metabolic Diseases Metabolism, Inborn Errors Mucinoses Mucopolysaccharidoses Mucopolysaccharidosis IV Nervous System Diseases Nutritional and Metabolic Diseases Pathologic Processes Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Aspiration Respiratory Tract Diseases Skin and Connective Tissue Diseases Sleep Apnea Syndromes Sleep Apnea, Central Sleep Disorders, Intrinsic Sleep Wake Disorders

Age range

18 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Guangzhou Medical University

Guangzhou, Guangdong, China

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • BMI less than 25kg/m2
  • normal lung function.
  • Healthy lowlanders (<500m) who have no history to travel to high altitude (>1000m) a year before the study.

Exclusion criteria

  • insomnia,
  • moderate or severe OSA based on PSG at sea level (AHI> 15 events/hr).
  • visited to an altitude >2500 m in the preceding year.
  • Currently using medicines for diabetes, hypertension et al.

Treatment and study plan

Breathing with CO2 during daytime and night at high altitude

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.

Other names: Sleep and doing exercise test under inhalation of CO2

Sleep and doing exercise test under inhalation of air

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.

Primary outcomes

  1. Incidence rate of acute mountain sickness (AMS)

    Time frame: 72 hours

    Incidence rate of AMS based on Louis's scores under inhalation of CO2 and ambient air. The maximum score is 12 points, and a score greater than 3 indicates the presence of AMS.

  2. The severity of AMS

    Time frame: 72 hours

    The severity of AMS based on Louis's scores under inhalation of CO2 and ambient air. A score of 3-5 indicates mild AMS, a score of 6-9 indicates moderate AMS and a score of 10-12 indicates severe AMS.

Secondary outcomes

  1. Central sleep apnea index based on PSG

    Time frame: 72 hours

    Changes of central sleep apnea index under inhalation of CO2 and ambient air.

  2. Sleep quality based on PSG

    Time frame: 72 hours

    Changes of sleep quality under inhalation of CO2 and ambient air.

  3. Workload in the incremental ergometer test

    Time frame: 72 hours

    Changes of workload in the incremental ergometer test under inhalation of CO2 and ambient air.

  4. Exercise duration in the incremental ergometer test

    Time frame: 72 hours

    Changes of exercise duration in the incremental ergometer test under inhalation of CO2 and ambient air.

Sponsors and collaborators

Lead sponsor

State Key Laboratory of Respiratory Disease

Other

Registry information

Official study title

CO2 Supplement for Prophylaxis and Treatment of Acute Mountain Sickness Using Novel Device

Important dates

Study start
2024
Primary completion
2024
Study completion
2024
First posted
May 1, 2024
Registry last updated
Dec 18, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.