Comparison between the phase angle and phase shift parameters to assess thoracoabdominal asynchrony in COPD patients.

Determining the presence of thoracoabdominal asynchrony in chronic obstructive pulmonary disease (COPD) patients is clinically relevant, but there is no consensus on the optimal parameters for performing this analysis. We assessed 22 COPD patients (FEV1 40 ± 10% predicted) and 13 healthy controls during rest and exercise with optoelectronic plethysmography (70% maximum workload) on a cycle ergometer. Thoracoabdominal asynchrony was calculated by using phase angle and phase shift parameters following a three-compartment model involving the upper and lower rib cages and abdomen. Patients were classified as having thoracoabdominal asynchrony (TAA+) or not (TAA-) based on control values (mean ± 2 SDs). The chest wall volume and compartmental contribution were also measured. Thoracoabdominal asynchrony was observed in the lower rib cage. The phase angle detected more TAA+ patients at rest (15 vs. 7 patients) and during exercise (14 vs. 8 patients) compared with the phase shift. TAA+ patients also presented a lower chest wall volume, lower rib cage contribution, and higher abdominal contribution to chest wall volume compared with the control and TAA- patients. Thoracoabdominal asynchrony was more detectable during rest and exercise using the phase angle parameter, and it was observed in the lower rib cage compartment, reducing the chest wall volume during exercise in patients with COPD.NEW & NOTEWORTHY This study contributes to advance the knowledge over the previous lack of consensus on the assessment of thoracoabdominal asynchrony. We rigorously evaluated the related features that interfere in the measurement of the asynchrony (measurement tool, chest wall model and calculation parameter). Our results suggest that phase angle detects more suitably thoracoabdominal asynchrony that occurs on the lower ribcage and leads to a reduction in the chest wall volume during exercise in COPD patients.

Pulmonary rehabilitation in lymphangioleiomyomatosis: a controlled clinical trial.

Lymphangioleiomyomatosis (LAM) is a cystic lung disease frequently associated with reduced exercise capacity. The aim of this study was to assess safety and efficacy of pulmonary rehabilitation in LAM.This controlled clinical trial included 40 patients with LAM and a low physical activity level. The pulmonary rehabilitation programme comprised 24 aerobic and muscle strength training sessions and education. The primary outcome was exercise capacity (endurance time during a constant work rate exercise test). Secondary outcomes included health-related quality of life (St George's Respiratory Questionnaire (SGRQ)), 6-min walking distance (6MWD), dyspnoea, peak oxygen consumption (V'O2 ), daily physical activity (pedometer), symptoms of anxiety and depression, lung function and peripheral muscle strength (one-repetition maximum).The baseline characteristics were well balanced between the groups. The pulmonary rehabilitation group exhibited improvements in the following outcomes versus controls: endurance time (median (interquartile range) 169 (2-303) s versus -33 (-129-39) s; p=0.001), SGRQ (median (interquartile range) -8 (-16-2) versus 2 (-4-5); p=0.002) and 6MWD (median (interquartile range) 59 (13-81) m versus 20 (-12-30) m; p=0.002). Dyspnoea, peak V'O2 , daily physical activity and muscle strength also improved significantly. No serious adverse events were observed.Pulmonary rehabilitation is a safe intervention and improves exercise capacity, dyspnoea, daily physical activity, quality of life and muscle strength in LAM.

Effect of volume-oriented versus flow-oriented incentive spirometry on chest wall volumes, inspiratory muscle activity, and thoracoabdominal synchrony in the elderly.

BACKGROUND: Aging causes physiological and functional changes that impair pulmonary function. Incentive spirometry is widely used for lung expansion, but the effects of volume-oriented incentive spirometry (VIS) versus flow-oriented incentive spirometry (FIS) on chest wall volumes, inspiratory muscle activity, and thoracoabdominal synchrony in the elderly are poorly understood. We compared VIS and FIS in elderly subjects and healthy adult subjects. METHODS: Sixteen elderly subjects (9 women, mean ± SD age 70.6 ± 3.9 y, mean ± SD body mass index 23.8 ± 2.5 kg/m(2)) and 16 healthy adults (8 women, mean ± age 25.9 ± 4.3 y, mean ± body mass index 23.6 ± 2.4 kg/m(2)) performed quiet breathing, VIS, and FIS in randomized sequence. Chest wall kinematics (via optoelectronic plethysmography) and inspiratory muscle activity (via surface electromyography) were assessed simultaneously. Synchrony between the superior thorax and abdominal motion was calculated (phase angle). RESULTS: In the elderly subjects both types of incentive spirometry increased chest wall volumes similarly, whereas in the healthy adult subjects VIS increased the chest wall volume more than did FIS. FIS and VIS triggered similar lower thoracoabdominal synchrony in the elderly subjects, whereas in the healthy adults FIS induced lower synchrony than did VIS. FIS required more muscle activity in the elderly subjects to create an increase in chest wall volume. CONCLUSIONS: Incentive spirometry performance is influenced by age, and the differences between elderly and healthy adults response should be considered in clinical practice.