Bronchodilators and Oxygen Kinetics With Exercise in Chronic Obstructive Pulmonary Disease (COPD) Patients

• Status: Completed
• Trial end date: 2009-07-01
• Target enrollment: 0
• Participant gender: All

Summary

Hypothesis: The reduction of dynamic hyperinflation and its negative effects on the respiratory system following a bronchodilator could lead to an improvement of cardiac function in terms of increased cardiac output. This may enhance oxygen delivery to the exercising muscles in COPD patients. Bronchodilator administration may also have an indirect effect on V'O2 kinetics via its action on cardiovascular and pulmonary variables.

Objectives:

1. To evaluate the effects of a bronchodilators on V'E , V'CO2 , and V'O2 kinetics in COPD during constant work-rate cycle exercise, and to evaluate whether bronchodilators will accelerate, indirectly, phase 2 kinetics (usually slower in COPD patients than normal subjects) and shorten t for V'E, V'CO2 , and V'O2 and shorten half-times for HR and O2 pulse, thus showing an improvement of oxygen transport to the peripheral active muscles.

2. To determine the impact of a bronchodilator-induced reduction in dynamic hyperinflation, and its effects on cardiovascular and pulmonary function, on exercise limitation in COPD.

• Phase: Phase 4
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Queen's University
• Treatments: Bronchodilator Agents; Ipratropium

Criteria

Inclusion Criteria:

• 40-80 years

• stable COPD

• FEV1 < 60 % predicted

• severe chronic breathlessness (Baseline Dyspnea Index < 6)

Exclusion Criteria:

• SpO2 at rest < 90% or a a sustained decrease of > 4% in arterial O2 saturation during the ergometer test, as determined by pulse oximetry

• a body mass index (BMI) < 19 or > 30

• chronic oral steroid therapy

• other medical conditions which could cause or contribute to breathlessness, i.e., heart disease or other respiratory diseases

• other problem which could interfere with carrying out of exercise testing, i.e., neuromuscular diseases, orthopedic diseases, etc.