NEW YORK (Reuters Health) – By reducing dyspnea and increasing exercise tolerance, breathing a mixture of 60% helium and 40% oxygen augments the benefits of physical rehabilitation in patients with chronic obstructive pulmonary disease (COPD), according to a prospective clinical trial conducted in Canada.

Reporting in the March issue of the journal Chest, Dr. Neil D. Eves at the University of Calgary and his associates note that breathing the gaseous mixture combines “the benefits of helium for decreasing airway resistance and expiratory flow limitation with the benefit of oxygen for reducing ventilatory demand.”

In the current study, they randomly assigned 38 patients with stable COPD to breathe hyperoxic helium or air during a pulmonary rehabilitation program, which included 90 minutes of exercise 3 days per week for 6 weeks. Aerobic exercise intensity on a cycle ergometer was initiated and advanced as tolerated.

Throughout the program, the hyperoxic helium group achieved a significantly higher exercise intensity and training duration than the control group without increasing exertional symptoms, the report indicates. In fact, in these patients, leg discomfort was reduced, ventilation and respiratory rate decreased, and inspiratory and expiratory times increased.

At the end of the 6 weeks, the hyperoxic helium group also had a greater change in constant-load exercise time (9.5 vs 4.3 minutes, p = 0.047). The patients on hyperoxic helium group also reported greater changes in health-related quality of life, as measured by St. George Respiratory Questionnaire scores (p = 0.049), which the authors say were “clinically meaningful.”

Dr. Eves’ group concludes: “This initial study … provides justification for performing a larger randomized controlled trial that directly compares hyperoxic helium to oxygen-supplementation in a real-world pulmonary rehabilitation setting.”

Reference:
Chest 2009;135:609-618.