Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity
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.
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Single-Breath Measurement Underestimates Ventilatory Volume According to Emphysema Severity|
|Study Start Date:||January 2006|
|Study Completion Date:||July 2007|
Patients with obstructive defects and radiological evidence of emphysema
Patients with obstructive ventilatory defects and no radiological evidence of emphysema
Non-smokers without obstructive ventilatory defects or history of cardiopulmonary disease
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.
|United States, New York|
|Columbia University Cardiopulmonary, Sleep and Ventilatory Disorders Center|
|NY, New York, United States, 10032|
|Principal Investigator:||Robert C Basner, MD||Columbia University|