Dynamic Hyperinflation and Tiotropium

Simplified Detection of Dynamic Hyperinflation Using Metronome Paced Hyperventilation and the Effect of Tiotropium in Patients With COPD

We will detect dynamic hyperinflation (DH) in 40 COPD (chronic obstructive pulmonary disease) patients with moderately severe disease using metronome paced hyperventilation (MPH) with inspiratory capacity as the primary end point. Hypothesis: Is tiotropium capable of lung volume protecting inspiratory capacity from MPH induced DH vs placebo in a randomized crossover double blinded study.

Study completed with 29 patients studied. Data is being analyzed to evaluate trough and peak effect of 18 µg tiotropium vs placebo on FEV 1 (L)(forced expiratory capacity in one second), inspiratory capacity and functional residual volume. In addition, we will study the effect of 18 µg tiotropium vs placebo on metronome paced hyperventilation induced dynamic hyperinflation. We will also evaluate the effect of tiotropium induced increase in IC (inspiratory capacity) vs extent of emphysema as evaluated on high resolution thin section CT lung

Inclusion Criteria:

• Moderately severe COPD patients age 40-85 yr with post 180ug albuterol FEV 1 between 60 and 79% predicted and FEV 1/FVC < 70%.
• Smoking history > 10 pack yr.
• Clinically stable X 6 weeks.
• No oxygen usage.

Exclusion Criteria:

• History of asthma
• Clinically unstable
• Any other significant medical problem precluding full cooperation for study