Zanotti E, Felicetti G, Maini M, Fracchia C. Chest. 2003;124:292-296.

Study objective: To compare the effects of active limb mobilization (ALM) with or without electrical stimulation (ES) on muscle strength, respiratory rate (RR), heart rate, oxygen saturation, and time needed to transfer from bed to chair in two groups of patients with COPD.

Design: Randomized, controlled study.

Setting: Respiratory high-dependency care unit.

Patients: Twenty-four bed-bound patients with chronic hypercapnic respiratory failure due to COPD who were receiving mechanical ventilation, with marked peripheral muscle hypotonia and atrophy.

Methods: Patients were randomly assigned either to ALM alone or to ALM plus ES (ALM/ES). ES was applied using square-wave alternate, symmetric, and compensated impulses for 30 min bid. The duration of treatment was 28 days for all patients.

Results: Muscle strength improved significantly in the overall group of patients (from 1.75 +/- 0.73 to 3.44 +/-0.65, P < 0.05). Comparing the change (end minus beginning) of the analyzed variables, ALM/ES significantly improved muscle strength (2.16 +/- 1.02 vs 1.25 +/- 0.75, P = 0.02) and RR (- 1.91 +/- 1.72 vs 0.41 +/- 1.88, P = 0.004), and decreased the number of days needed to transfer from bed to chair (10.75 +/- 2.41 days vs 14.33 +/- 2.53 days, P = 0.001).

Conclusions: In bed-bound patients with COPD receiving mechanical ventilation, with marked peripheral muscle hypotonia and atrophy, application of ES in addition to classical ALM significantly improved muscle strength and decreased the number of days needed to transfer from bed to chair.

Comments: Patients hospitalized with acute exacerbations of COPD often experience a significant decline in functional status during and in the weeks following an exacerbation. It is difficult if not impossible for patients to maintain their activity and conditioning in the setting of an acute exacerbation. Patients who require hospitalization and especially those who require mechanical ventilation are particularly likely to have a decline in functional status, and they are unable to maintain an exercise program during the period of hospitalization. In this study, the investigators examined whether transcutaneous electrical stimulation of the skeletal muscle could alter muscle function of bed-bound patients with profound weakness who were receiving mechanical ventilation. Previous studies have shown that such treatment improves the exercise capacity of outpatients with stable COPD (Bourjeily G ^AQ et al, Thorax 2003). Muscle strength and number of days needed to transfer from bed to chair were significantly improved after this intervention. This technique is a promising methodology for the hospital-based rehabilitation of severely impaired persons with COPD and other forms of chronic respiratory disease who are unable to exercise.