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Pressure Dependent Tracheal Obstruction in Copd Patients (PDTO)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT01679808
Recruitment Status : Completed
First Posted : September 6, 2012
Last Update Posted : September 6, 2012
Information provided by (Responsible Party):

Study Description
Brief Summary:

Background. Do pressure dependent tracheal obstructions (PDTO) often seen during bronchoscopy in COPD patients affect pulmonary function tests and breathing symptoms? Method. Model study. A garden hose was compressed from one side to simulate the posterior wall of the trachea bulging into the lumen. For two obstruction lengths - 3 cm and 12 cm, the hose was increasingly compressed in eight steps. Resistance was measured at each step for airflows 1 l/s through 9 l/s, and digital photos of the luminal area were taken which were used by a computer to estimate the cross sectional area reduction and the corresponding distance between the bulging (posterior)and the opposite (anterior) wall (AP-distance).

Patient study. 104 stable COPD patients studied by pulmonary function tests and bronchoscopy. The tracheal obstruction was observed during forced expiration and cough, and the cross sectional area reduction was estimated using the results from the model study.

Condition or disease

Study Design

Study Type : Observational
Actual Enrollment : 104 participants
Observational Model: Case-Only
Time Perspective: Cross-Sectional
Official Title: Pressure Dependent Tracheal Obstruction in Copd Patients
Study Start Date : August 2004
Primary Completion Date : August 2006
Study Completion Date : August 2011

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Groups and Cohorts

Outcome Measures

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   Child, Adult, Senior
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients (both sexes) in a pulmonary rehabilitation clinic

Inclusion Criteria:

  • copd

Exclusion Criteria:

  • clinical evidence of malignant disease
  • not able to be subjected to bronchoscopy
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01679808

Hakadal, Akershus, Norway, 1485
Sponsors and Collaborators
LHL Helse
Principal Investigator: Ivar Ellingsen, Dr med LHL Helse
More Information

Responsible Party: LHL Helse
ClinicalTrials.gov Identifier: NCT01679808     History of Changes
Other Study ID Numbers: GK-18
s-04058c ( Registry Identifier: The National Committees for Research Ethics in Norway )
First Posted: September 6, 2012    Key Record Dates
Last Update Posted: September 6, 2012
Last Verified: September 2012

Keywords provided by LHL Helse:
airway obstruction

Additional relevant MeSH terms:
Cartilage Diseases
Musculoskeletal Diseases
Bronchial Diseases
Respiratory Tract Diseases
Tracheal Diseases
Musculoskeletal Abnormalities
Congenital Abnormalities
Connective Tissue Diseases