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Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00528944
First Posted: September 14, 2007
Last Update Posted: July 7, 2015
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.
Information provided by (Responsible Party):
Columbia University
  Purpose
Although single breath helium (He) dilution measurement (VASB) is currently used in pulmonary function laboratories to assess functional alveolar volume and diffusing capacity for carbon monoxide, the extent to which VASB reflects ventilatory and thoracic volume has not been prospectively determined in emphysema. We hypothesized that VASB underestimates rebreathe helium dilution volume (VARB), and plethysmographic volume (VApleth) as clinical and physiologic severity of emphysema increases.

Condition
Emphysema

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity

Resource links provided by NLM:


Further study details as provided by Columbia University:

Primary Outcome Measures:
  • Difference between DLCO SB alveolar volume and the total lung volume measurement from plethysmography [ Time Frame: 10 seconds ]
    To test the hypothesis that DLCO SB underestimates DLCO derived by the re-breathe DLCO maneuver, and that VA SB similarly underestimates VA RB. Alveolar volume derived with the two maneuvers will be compared with body plethysmography, the gold standard of total lung volume measurement in patients with emphysema.

  • Difference between DLCO RB alveolar volume and the total lung volume measurement from plethysmography [ Time Frame: 10 seconds ]
    To test the hypothesis that DLCO SB underestimates DLCO derived by the re-breathe DLCO maneuver, and that VA SB similarly underestimates VA RB. Alveolar volume derived with the two maneuvers will be compared with body plethysmography, the gold standard of total lung volume measurement in patients with emphysema.


Enrollment: 73
Study Start Date: January 2006
Study Completion Date: July 2008
Primary Completion Date: July 2008 (Final data collection date for primary outcome measure)
Groups/Cohorts
Cohort A
Patients with obstructive defects and radiological evidence of emphysema
Cohort B
Patients with obstructive ventilatory defects and no radiological evidence of emphysema
Cohort C
Non-smokers without obstructive ventilatory defects or history of cardiopulmonary disease

Detailed Description:
VASB, VARB, and VApleth were measured in 52 consecutive stable outpatients with clinical and radiographic emphysema. Thirteen patients with an obstructive ventilatory defect without emphysema (OVD) and 18 normal controls were similarly studied. All subjects underwent spirometry followed by whole body plethysmography and He dilution volume measurements; VASB and VARB order was randomized.
  Eligibility

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Ages Eligible for Study:   18 Years to 81 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
This is a prospective trial in all outpatients with emphysema referred for full pulmonary function testing to the pulmonary diagnostic unit.
Criteria

Inclusion Criteria:

  • All outpatients between the ages of 18 and 81 years referred to the Columbia University Medical Center Pulmonary Diagnostic Unit between 1/18/06 and 7/30/07 for full pulmonary function evaluation, and with an obstructive ventilatory defect on spirometry, were considered eligible.

Exclusion Criteria:

  • Patients who did not want to undergo the re-breathe diffusing capacity testing
  • Patients who could not give informed consent;and
  • Patients who were too physically compromised to undergo full testing including the re-breathe maneuver as deemed by our technicians.
  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): NCT00528944


Locations
United States, New York
Columbia University Cardiopulmonary, Sleep and Ventilatory Disorders Center
NY, New York, United States, 10032
Sponsors and Collaborators
Columbia University
Investigators
Principal Investigator: Robert C Basner, MD Columbia University
  More Information

Responsible Party: Columbia University
ClinicalTrials.gov Identifier: NCT00528944     History of Changes
Other Study ID Numbers: AAAB6328
First Submitted: September 11, 2007
First Posted: September 14, 2007
Last Update Posted: July 7, 2015
Last Verified: July 2015

Keywords provided by Columbia University:
alveolar volume
pulmonary function testing
emphysema

Additional relevant MeSH terms:
Emphysema
Pulmonary Emphysema
Pathologic Processes
Pulmonary Disease, Chronic Obstructive
Lung Diseases, Obstructive
Lung Diseases
Respiratory Tract Diseases