Effect of High Levels of Oxygen and Smoking on the Lungs in Human Volunteers

Healthy Volunteers Clinical Trial

Official title:

Effect of Hypoxia and Smoking on Oxidation of Proteins and Nucleic Acids in Human Volunteers

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00001464
• Other study ID #: 950167
• Secondary ID: 95-H-0167
• Status: Completed
• Start date: August 22, 1995
• Est. completion date: July 10, 2007

Study information

• Verified date: August 2021
• Source: National Institutes of Health Clinical Center (CC)
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Patients with lung disease experiencing difficulty breathing can be treated with oxygen therapy. This involves the delivery of "extra" oxygen by a face-mask or through small tubes placed in the nose called nasal prongs. This extra oxygen can have concentrations as high as 100% pure oxygen. The concentration of oxygen in normal air is only 21%. The high concentration of oxygen can help to provide enough oxygen for all of the organs in the body. Unfortunately, breathing 100% oxygen for long periods of time can cause changes in the lungs, which are potentially harmful. Researchers believe that by lowering the concentration of oxygen therapy to 40% patients can receive it for longer periods of time without the risk of side effects.

This study is designed to evaluate the effects of oxygen therapy at 100% and 40% for 12 18 hours on the lungs of normal volunteers. Results of this study will help to determine if levels of oxygen therapy currently accepted as being "safe" may actually be damaging to the lungs.

Description:

Stress such as high oxygen or inflammation can result in damage to proteins by processes such as oxidation or alternative regulation of signaling pathways by post-translational modification of proteins (e.g., phosphorylation). Delivery of oxygen in high concentrations to the lungs can result in damage, which is mediated in large part by reactive oxygen species. Inflammation can result in activation of intracellular signaling pathways. This study will evaluate modification of proteins and nucleic acids in bronchoalveolar lavage fluid, bronchial epithelial cells, and peripheral blood of individuals exposed to oxygen or who are smokers. In doing so, it will determine the effects of hyperoxia or inflammation on the lung.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 77
• Est. completion date: July 10, 2007
• Est. primary completion date: July 10, 2007
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

• INCLUSION CRITERIA:

History - good overall health without history of recent (within 3 months) acute disease;

Physical examination within normal limits;

Laboratory evaluation; including complete blood count (CBC), serum electrolyte determinations, clotting times, chest x-ray, pulmonary function testing, and an electrocardiogram (EKG) - within normal limits;

Non-smokers defined as having never smoked or not smoked in the past 2 years;

Smokers defined as moderate (1 pack per day for 3+ years) or heavy (1-2 packs for 10+ years);

Subjects must be willing to make the time commitment necessary for the study.

EXCLUSION CRITERIA:

Any study subject who does not fulfill the criteria for eligibility.

Individuals with a history of allergy or adverse reactions to atropine or any local anesthetic;

Individuals testing positive for the human immunodeficiency virus or hepatitis virus;

Individuals on chronic medications or currently receiving medications;

Pregnant or lactating individuals, since the effects of hyperoxia on the fetus are unclear.

Related Conditions & MeSH terms

• Healthy Volunteers

Locations

Country	Name	City	State
United States	National Institutes of Health Clinical Center, 9000 Rockville Pike	Bethesda	Maryland

Sponsors (1)

Lead Sponsor	Collaborator
National Heart, Lung, and Blood Institute (NHLBI)

Country where clinical trial is conducted

United States, 

References & Publications (3)

Davis WB, Rennard SI, Bitterman PB, Crystal RG. Pulmonary oxygen toxicity. Early reversible changes in human alveolar structures induced by hyperoxia. N Engl J Med. 1983 Oct 13;309(15):878-83. — View Citation

Deneke SM, Fanburg BL. Normobaric oxygen toxicity of the lung. N Engl J Med. 1980 Jul 10;303(2):76-86. Review. — View Citation

Erzurum SC, Danel C, Gillissen A, Chu CS, Trapnell BC, Crystal RG. In vivo antioxidant gene expression in human airway epithelium of normal individuals exposed to 100% O2. J Appl Physiol (1985). 1993 Sep;75(3):1256-62. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	To determine whether hyperoxia of relatively limited duration (up to l8 hrs) is associated with oxidation of proteins and nucleic acids in lung cells.	To determine whether hyperoxia of relatively limited duration (up to l8 hrs) is associated with oxidation of proteins and nucleic acids in lung cells.	1 week

External Links

•   NIH Clinical Center Detailed Web Page