Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity

Emphysema Clinical Trial

Official title:

Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00528944
• Other study ID #: AAAB6328
• Status: Completed
• Phase: N/A
• First received: September 11, 2007
• Last updated: July 2, 2015
• Start date: January 2006
• Est. completion date: July 2008

Study information

• Verified date: July 2015
• Source: Columbia University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 73
• Est. completion date: July 2008
• Est. primary completion date: July 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 81 Years

Eligibility

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.

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Emphysema
• Pulmonary Emphysema

Locations

Country	Name	City	State
United States	Columbia University Cardiopulmonary, Sleep and Ventilatory Disorders Center	NY	New York

Sponsors (1)

Lead Sponsor	Collaborator
Columbia University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Difference between DLCO SB alveolar volume and the total lung volume measurement from plethysmography	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.	10 seconds	No
Primary	Difference between DLCO RB alveolar volume and the total lung volume measurement from plethysmography	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.	10 seconds	No