Effects of a walking aid in COPD patients receiving oxygen therapy.

STUDY OBJECTIVES

To elucidate whether a simple walking aid may improve physical performance in COPD patients with chronic respiratory insufficiency who usually carry their own heavy oxygen canister.

DESIGN

Randomized crossover trial.

SETTING

Physiopathology laboratory of three rehabilitation centers.

PATIENTS AND INTERVENTIONS

We studied 60 stable COPD patients (mean age, 70.6 +/- 7.9 years; FEV(1), 44.8 +/- 14.3% of predicted [+/- SD]) with chronic respiratory insufficiency who randomly performed, on 2 consecutive days, a standardized 6-min walking test using two different modalities: a full-weight oxygen canister transported using a small wheeled cart and pulled by the patient (Aid modality) or full-weight oxygen canister carried on the patient's shoulder (No-Aid modality).

MEASUREMENTS AND RESULTS

The distance walked, peak effort dyspnea, and leg fatigue scores as primary outcomes, and other cardiorespiratory parameters as secondary outcomes were recorded during both tests. A significant difference (p < 0.05) between the two tests occurred for all the measured outcomes in favor of the Aid modality. Most importantly, significant changes for distance (+ 43 m, p < 0.001), peak effort dyspnea (- 2.0 points, p < 0.001), leg fatigue (- 1.4 points, p < 0.001), as well as for mean and nadir oxygen saturation and heart rate with the Aid modality (but not with the No-Aid modality) were recorded in the subgroup of patients walking < 300 m at baseline.

CONCLUSIONS

This study suggests that a simple walking aid may be helpful in COPD patients receiving long-term oxygen therapy, particularly in those with lower residual exercise capacity.