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Pressure Dependent Tracheal Obstruction in Copd Patients (PDTO)

This study has been completed.
Information provided by (Responsible Party):
LHL Helse Identifier:
First received: September 3, 2012
Last updated: NA
Last verified: September 2012
History: No changes posted

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.


Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Cross-Sectional
Official Title: Pressure Dependent Tracheal Obstruction in Copd Patients

Resource links provided by NLM:

Further study details as provided by LHL Helse:

Enrollment: 104
Study Start Date: August 2004
Study Completion Date: August 2011
Primary Completion Date: August 2006 (Final data collection date for primary outcome measure)

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
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Please refer to this study by its identifier: NCT01679808

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

Responsible Party: LHL Helse Identifier: NCT01679808     History of Changes
Other Study ID Numbers: GK-18
s-04058c ( Registry Identifier: The National Committees for Research Ethics in Norway )
Study First Received: September 3, 2012
Last Updated: September 3, 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 processed this record on September 21, 2017