Effect of Supplemental Oxygen on Maximal Oxygen Consumption in Patients With Chronic Obstructive Pulmonary Disease

• Minute ventilation - Carbon dioxide production slope [ Time Frame: Outcomes are measured at time of study visit when patient reaches maximal exercise during cardiopulmonary exercise test. Measurements occur at time of test within 30 minutes of exercise. This is not a longitudinal study measuring outcomes over time. ] [ Designated as safety issue: No ]
• Exercise time [ Time Frame: Outcomes are measured at time of study visit when patient reaches maximal exercise during cardiopulmonary exercise test. Measurements occur at time of test within 30 minutes of exercise. This is not a longitudinal study measuring outcomes over time. ] [ Designated as safety issue: No ]
• Oxygen saturation [ Time Frame: Outcomes are measured at time of study visit when patient reaches maximal exercise during cardiopulmonary exercise test. Measurements occur at time of test within 30 minutes of exercise. This is not a longitudinal study measuring outcomes over time. ] [ Designated as safety issue: No ]
• Maximum watts achieved [ Time Frame: Outcomes are measured at time of study visit when patient reaches maximal exercise during cardiopulmonary exercise test. Measurements occur at time of test within 30 minutes of exercise. This is not a longitudinal study measuring outcomes over time. ] [ Designated as safety issue: No ]
• Maximum minute ventilation [ Time Frame: Outcomes are measured at time of study visit when patient reaches maximal exercise during cardiopulmonary exercise test. Measurements occur at time of test within 30 minutes of exercise. This is not a longitudinal study measuring outcomes over time. ] [ Designated as safety issue: No ]

Maximal consumption of oxygen (VO2max) during exercise is used in patients with chronic obstructive pulmonary disease (COPD) to stratify perioperative risk. However, the impact of supplemental oxygen to prevent hypoxemia during exercise on maximal oxygen consumption and other ventilatory parameters during maximal exercise in the resting normoxic Chronic Obstructive Pulmonary Disease population is poorly defined. The investigators performed a randomized controlled trial in patients with COPD who underwent cardiopulmonary exercise tests on room air and supplemental oxygen. The investigators compared maximal oxygen consumption and other ventilatory parameters in each individual subject under the two conditions.

• Other: Fractional inspired oxygen (FiO2) 0.21
• Other: Fractional inspired oxygen 0.28
  Supplemental oxygen

• Placebo Comparator: Fractional inspired oxygen 0.21
  Cardiopulmonary exercise test performed by subject on Fractional inspired oxygen 0.21
  Intervention: Other: Fractional inspired oxygen (FiO2) 0.21
• Active Comparator: Fractional inspired oxygen 0.28
  Cardiopulmonary exercise test performed on supplemental oxygen (Fractional inspired oxygen 0.28)
  Intervention: Other: Fractional inspired oxygen 0.28

Inclusion Criteria:

• Clinical diagnosis of Chronic Obstructive Pulmonary Disease (COPD).
• Pulmonary function characterized by forced expiratory volume in 1 second/forced vital capacity ratio<0.7, and forced expiratory volume in one second <80% predicted.

Exclusion Criteria:

• Subjects with a recent COPD exacerbation requiring emergency department visit or hospitalization within the last month.
• Subjects scheduled for a major pulmonary intervention in the next 3 months
• Subjects with severe peripheral vascular disease or other physical conditions that would preclude exercise testing