Inspiratory muscle training for patients with chronic obstructive pulmonary disease: a practical guide for clinicians.

Reduced inspiratory muscle strength is common in people with chronic obstructive pulmonary disease (COPD) and is associated with dyspnea and decreased exercise capacity. Most studies of inspiratory muscle training (IMT) in COPD have demonstrated increased inspiratory muscle strength. Many have also shown improvements in dyspnea and exercise capacity. However, a persisting challenge when translating and applying the findings of these studies in clinical practice is the disparity in training loads, modalities, and outcomes measures used in the different studies. This commentary summarizes our clinical and research experience with a threshold IMT device with the aim of providing clinicians interested in prescribing IMT in this population with practical recommendations regarding patient selection, assessment, and implementation of training. We propose using an interval-based high-intensity threshold IMT program for people who are unable to participate fully in whole-body exercise training because of comorbidities such as severe musculoskeletal problems. Initial training loads equivalent to at least 30% of a person's maximum inspiratory pressure (PImax) are required for all people undertaking IMT. Supervision, which includes monitoring of oxygen saturation throughout the first training session, is recommended, and patients are warned to expect transient delayed-onset muscle soreness, a consequence of muscle adaptation to an unaccustomed activity. We recommend training be undertaken 3 times a week for 8 weeks, with loads progressively increased as symptoms permit. It is prudent to exclude people at risk of pneumothorax or spontaneous rib fracture. Evaluation of IMT should include measures of PImax, dyspnea, health-related quality of life, and exercise capacity.

The effects of pulmonary rehabilitation in patients with non-cystic fibrosis bronchiectasis: protocol for a randomised controlled trial.

BACKGROUND: Non-cystic fibrosis bronchiectasis is characterised by sputum production, exercise limitation and recurrent infections. Although pulmonary rehabilitation is advocated for this patient group, its effects are unclear. The aims of this study are to determine the short and long term effects of pulmonary rehabilitation on exercise capacity, cough, quality of life and the incidence of acute pulmonary exacerbations. METHODS/DESIGN: This randomised controlled trial aims to recruit 64 patients with bronchiectasis from three tertiary institutions. Participants will be randomly allocated to the intervention group (supervised, twice weekly exercise training with regular review of airway clearance therapy) or a control group (twice weekly telephone support). Measurements will be taken at baseline, immediately following the intervention and at six and 12 months following the intervention period by a blinded assessor. Exercise capacity will be measured using the incremental shuttle walk test and the six-minute walk test. Quality of life and health status will be measured using the Chronic Respiratory Questionnaire, Leicester Cough Questionnaire, Assessment of Quality of Life Questionnaire and the Hospital Anxiety and Depression Scale. The rate of hospitalisation will be captured as well as the incidence of acute pulmonary exacerbations using a daily symptom diary. DISCUSSION: Results from this study will help to determine the efficacy of supervised twice-weekly pulmonary rehabilitation upon exercise capacity and quality of life in patients with bronchiectasis and will contribute to clinical practice guidelines for physiotherapists in the management of this population. TRIAL REGISTRATION: This study protocol is registered with ClinicalTrials.gov (NCT00885521).

Feasibility of high-intensity, interval-based respiratory muscle training in COPD.

BACKGROUND: Specific respiratory muscle training can improve respiratory muscle function in patients with COPD, but the magnitude of improvement appears dependent on the magnitude of the training load. High training loads are difficult to achieve using conventional, constant loading techniques, but may be possible using interval-based training techniques. METHODS: To assess the feasibility of high-intensity respiratory muscle training, nine subjects with moderate-to-severe COPD (FEV(1) 34 +/- 12% predicted [mean +/- SD]) completed 8 weeks of interval-based respiratory muscle training combined with a general exercise program. This involved three 20-min sessions per week, each session comprising seven 2-min bouts of breathing against a constant inspiratory threshold load, each bout separated by 1 min of unloaded recovery. Inspiratory load was progressively incremented. Respiratory muscle strength (maximum inspiratory pressure generated against an occluded airway [PImax]) and endurance (maximum pressure generated against a progressively increasing inspiratory threshold load [Pthmax]) were measured before and immediately after the 8-week training period. RESULTS: By the third training session (week 1), subjects breathed against a threshold that required generation of pressures equivalent to 68 +/- 5% of the pretraining PImax. By week 8, this had increased to 95 +/- 12% of the pretraining PImax. On completion of training, PImax had increased by 32 +/- 27% (p < 0.05), Pthmax had increased by 56 +/- 33% (p < 0.05), and Pthmax/PImax had increased by 20 +/- 20% (p < 0.05). CONCLUSIONS: This study has demonstrated that high-intensity, interval-based respiratory muscle training is feasible in patients with moderate-to-severe COPD, resulting in significant improvements in respiratory muscle strength and endurance when performed three times a week for 8 weeks.