Induced Changes in Ventilatory Responsiveness and Altitude Exposure
Condition: Effects of High Altitude; Hypoxia; Inadequate or Impaired Breathing Pattern or Ventilation; Abnormal Blood Oxygen Pressure
MeSH terms: Altitude Sickness; Hypoxia
Intervention: NAC; Placebo
Intervention description: NAC provided to determine if beneficial at altitude; Placebo
Phase: Phase 4
Study type: Interventional
Primary purpose: Basic Science
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Enrollment: 21.0
Sex: All
Minimum age: 18 Years
Maximum age: 39 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: glutathione; redox status; carotid body chemosensitivity; ventilation

Summary:

      The main purpose of this study is to determine if a drug (acetyl-cysteine or ACCY) can
      increase the amount of oxygen in your body at a high altitude of 11,500 feet. ACCY is
      approved by the Food and Drug Administration (FDA) as a treatment or antidote for Tylenol
      overdoses. Other forms of ACCY are also sold over-the-counter as nutritional supplements. In
      this study, the FDA-approved form of ACCY will be used "off-label" (meaning in a way not
      approved by the FDA).

      This study is being conducted by researchers from the United States Army Research Institute
      of Environmental Medicine (USARIEM). The study will take place in the Altitude Chamber
      located in the basement of USARIEM. A total of approximately 30 volunteers (men and women,
      military and civilians) will take part in the study. They can expect to be in the study for a
      minimum of a few hours each day for two weeks.

      The investigators hypothesize that ACCY will improve ventilation and oxygenation while at
      altitude.
    

Eligibility criteria:

        Inclusion Criteria:

        -

        Exclusion Criteria:

          -  Volunteers with the following criteria will be EXCLUDED from participation:

        Less than 18 years of age Greater than 39 years of age Born at altitudes greater than 2134
        m (7000 ft) Living in areas that are more than 1220 m (4,000 feet), or have traveled to
        areas that are more than 1220 m for more than a few days within the last 2 months.

        Abnormal [Hb]/Hct levels or presence of hemoglobin S Known allergies to sulfonamide
        derivatives Smokers who smoke more than 5 cigarettes per day Tobacco chewers If military,
        unable to pass the 2-mi run portion of the Army Physical Fitness Test, or equivalent If
        civilian, not currently running or exercising for at least 20 min/day, 3X/week in "aerobic"
        activities (e.g., running, biking. swimming, basketball, etc) If they do not want to walk
        or run multiple times for 1 to 3 hours on a treadmill Unable to meet the U.S. Army
        height/weight standards Not willing to sleep in bunk beds in a small room (8 feet by 8
        feet) with 1 to 3 other volunteers (male and/or female) for 3 nights. If they are
        claustrophobic Women who are pregnant or planning to conceive during the study period Women
        who are not willing to take urine pregnancy tests Not willing to drink an eight ounce
        solution of diet soda that may contain ACCY up to three times per day and then not willing
        to suck on a peppermint mint right after drinking the solution.

        Taking medications that interfere with oxygen delivery and transport (Includes sedatives,
        sleeping aids, tranquilizers and any medication that depresses ventilation, diuretics,
        alpha and beta blockers) Evidence of any physical, mental, and/or medical conditions that
        would make the proposed studies relatively more hazardous. Evidence of prior HAPE or HACE
        diagnosis Evidence of apnea or other sleeping disorders Evidence of asthma If applicable,
        unwilling to stop taking all supplements for the two weeks of participation If applicable,
        all medications (prescription or over-the-counter) must be approved by the PI, and/or the
        OMSO.