Breathing Hydrogen-Oxygen Mixture Decreases Inspiratory Effort in Patients with Tracheal Stenosis.

BACKGROUND: Hydrogen-oxygen mixture (H2-O2) may reduce airway resistance in patients with acute severe tracheal stenosis, yet data supporting the clinical use of H2-O2 are insufficient. OBJECTIVES: To evaluate the efficacy and safety of breathing H2-O2 in acute severe tracheal stenosis. METHODS: Thirty-five consecutive patients with severe acute tracheal stenosis were recruited in this prospective self-control study. Air, H2-O2 and O2 inhalation was given in 4 consecutive breathing steps: air for 15 min, H2-O2 (6 L per min, H2:O2 = 2: 1) for 15 min, oxygen (3 L per min) for 15 min, and H2-O2 for 120 min. The primary endpoint was inspiratory effort as assessed by diaphragm electromyography (EMGdi); the secondary endpoints were transdiaphragmatic pressure (Pdi), Borg score, vital signs, and impulse oscillometry (IOS). The concentration of H2 in the ambient environment was obtained with 12 monitors. Adverse reactions during the inhalation were recorded. RESULTS: The mean reduction in the EMGdi under H2-O2 was 10.53 ± 6.83%. The EMGdi significantly decreased during 2 H2-O2 inhalation steps (Steps 2 and 4) compared with air (Step 1) and O2 (Step 3) (52.95 ± 15.00 vs. 42.46 ± 13.90 vs. 53.20 ± 14.74 vs. 42.50 ± 14.12% for Steps 1 through 4, p < 0.05). The mean reduction in the Pdi under H2-O2 was 4.77 ± 3.51 cmH2O. Breathing H2-O2 significantly improved the Borg score and resistance parameters of IOS but not vital signs. No adverse reactions occurred. H2 was undetectable in the environment throughout the procedure. CONCLUSIONS: Breathing H2-O2 may reduce the inspiratory effort in patients with acute severe tracheal stenosis and can be used for this purpose safely.

Impacts of anti-inflammatory phosphodiesterase inhibitors on a murine model of chronic pulmonary inflammation.

Chronic obstructive pulmonary disease (COPD) often tends to respond poorly to glucocorticoid (GC) therapy. Reduced Histone deacetylase-2 (HDAC-2) activity is an important mechanism behind this GC insensitivity. In this study, we investigated the effects of three phosphodiesterase inhibitors (PDEIs), with an anti-inflammatory propensity, on cigarette smoke (CS)-induced pulmonary inflammation and HDAC-2 activity. Male C57BL/6 mice were exposed to cigarette smoke (CS) over the course of 30 weeks. Administration of the PDEIs commenced from the 29th week and followed a schedule of once daily treatments, 5 days a week, for 2 weeks. Roflumilast (ROF) was administered intragastrically (5 mg·kg-1 ), while pentoxifylline (PTX) (10 mg·kg-1 ) and theophylline (THEO) (10 mg·kg-1 ) were administered intraperitoneally, either alone or in combination with a GC (triamcinolone acetonide or TRI, 5 mg·kg-1 , i.m., single injection). Lung morphometry, as well as the activity of HDAC-2, pro-inflammatory cytokines and reactive oxygen species (ROS) were assessed at the end of the 30-week course. CS exposure was associated with a reduction in HDAC-2 activity and the up-regulation of ROS expression. PTX, ROF, and THEO administration led to the partial restoration of HDAC-2 activity, which was favorably associated with the reduction of ROS expression. However, combining TRI to any of these PDEIs did not synergistically augment HDAC-2 activity. Inactivation of HDAC-2 due to long-term CS exposure is closely related to exaggerated oxidative stress, and this reduced HDAC-2 activity could partially be restored through the use of PDEIs. This finding provides a potential novel approach for further clinical research.

Efficacy of patients' preferred exercise modalities in chronic obstructive pulmonary disease: A parallel-group, randomized, clinical trial.

INTRODUCTION: Physical exercise effectively improves health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). However, application of this medical intervention is problematic, due to poor adherence to the exercise program or unawareness of the significance of this intervention. OBJECTIVE: To determine whether COPD patients who adopted personal-preferred exercise modalities (PPEMs) for daily training would demonstrate sustained benefits due to improved adherence. METHODS: Stable COPD patients were randomly assigned to the daily PPEMs group or the control group (without extra exercise apart from daily life activities). All other treatments were similar. The primary outcome was the health-related quality of life (HRQoL), measured with St. George's Respiratory Questionnaire (SGRQ) score at 12 months. Other measures included the Borg dyspnea score, 6-min walking distance (6MWD) and lung function variables. RESULTS: The intention-to-treat (ITT) population included 94 patients, 68 of them completed the study protocol over 12 months (the PP-population). A greater decline of SGRQ score (improvement of HRQoL) in the PPEMs group than that in the controls was demonstrated over 12 months (-19.1 vs -9.0 in the ITT population and -19.1 vs -8.7 in the PP population, P ≤ .001 for all comparisons), the reduction exceeded the minimal clinically important difference of ≥ 4 points. The PPEMs group also showed a greater reduction than the control group in Borg score at 12 months in the ITT and the PP population as well (P < .01). No significant improvement was found in 6MWD or in lung function variables. CONCLUSIONS: COPD patients could benefit from extra daily PPEMs, and the gain may sustain at least for 1 year.

Cycle ergometer and inspiratory muscle training offer modest benefit compared with cycle ergometer alone: a comprehensive assessment in stable COPD patients.

BACKGROUND: Cycle ergometer training (CET) has been shown to improve exercise performance of the quadriceps muscles in patients with COPD, and inspiratory muscle training (IMT) may improve the pressure-generating capacity of the inspiratory muscles. However, the effects of combined CET and IMT remain unclear and there is a lack of comprehensive assessment. MATERIALS AND METHODS: Eighty-one patients with COPD were randomly allocated to three groups: 28 received 8 weeks of CET + IMT (combined training group), 27 received 8 weeks of CET alone (CET group), and 26 only received 8 weeks of free walking (control group). Comprehensive assessment including respiratory muscle strength, exercise capacity, pulmonary function, dyspnea, quality of life, emotional status, nutritional status, and body mass index, airflow obstruction, and exercise capacity index were measured before and after the pulmonary rehabilitation program. RESULTS: Respiratory muscle strength, exercise capacity, inspiratory capacity, dyspnea, quality of life, depression and anxiety, and nutritional status were all improved in the combined training and CET groups when compared with that in the control group (P<0.05) after pulmonary rehabilitation program. Inspiratory muscle strength increased significantly in the combined training group when compared with that in the CET group (ΔPImax [maximal inspiratory pressure] 5.20±0.89 cmH2O vs 1.32±0.91 cmH2O; P<0.05). However, there were no significant differences in the other indices between the two groups (P>0.05). Patients with weakened respiratory muscles in the combined training group derived no greater benefit than those without respiratory muscle weakness (P>0.05). There were no significant differences in these indices between the patients with malnutrition and normal nutrition after pulmonary rehabilitation program (P>0.05). CONCLUSION: Combined training is more effective than CET alone for increasing inspiratory muscle strength. IMT may not be useful when combined with CET in patients with weakened inspiratory muscles. Nutritional status had slight impact on the effects of pulmonary rehabilitation. A comprehensive assessment approach can be more objective to evaluate the effects of combined CET and IMT.

Effectiveness of neuromuscular electrical stimulation for the rehabilitation of moderate-to-severe COPD: a meta-analysis.

PURPOSE: Patients with COPD often experience skeletal muscle dysfunction. For those who are unable or unwilling to undertake physical training, neuromuscular electrical stimulation (NMES) may provide an alternative method of rehabilitation. The purpose of this meta-analysis was to investigate the controversial topic of whether this therapy is effective in patients with moderate-to-severe COPD. PATIENTS AND METHODS: We pooled data from nine trials published between January 9, 2002 and January 4, 2016 across PubMed, Embase, Cochrane Central Register of Controlled Trials, Google Scholar, and relevant websites for randomized controlled trials. In these trials, patients with moderate-to-severe COPD were randomly allocated to receive NMES. Primary outcomes were quadricep strength and exercise capacity. The secondary outcome was health-related quality of life. RESULTS: We extracted data from 276 patients. NMES contributed to statistically improved quadricep strength (standardized mean difference 1.12, 95% confidence interval [CI] 0.64-1.59, I2=54%; P<0.00001) and exercise capacity, including longer exercise distance (weighted mean difference 51.53, 95% CI 20.13-82.93, I2=90%; P=0.001), and longer exercise endurance (standardized mean difference 1.11, 95% CI 0.14-2.08, I2=85%; P=0.02). There was no significant difference in St George's Respiratory Questionnaire scores (weighted mean difference -0.07, 95% CI -2.44 to 2.30, I2=56%; P=0.95). CONCLUSION: NMES appears an effectual means of enhancing quadricep strength and exercise capacity in moderate-to-severe COPD patients. Further research is demanded to clarify its effect on other outcomes and determine the optimal parameters for an NMES program.

The relationship between sleep quality and functional exercise capacity in COPD.

BACKGROUND: Poor sleep is often associated with a series of health problems in patients with chronic obstructive pulmonary disease (COPD), but the relationship between sleep quality and functional exercise capacity has not been previously investigated. AIMS: To evaluate the relationship between quality of sleep and functional exercise capacity in clinically stable COPD. METHODS: One hundred three consecutive subjects with stable COPD were recruited. The subjects were assessed with the Pittsburgh Sleep Quality Index (PSQI) and divided into poor sleep group (PSQI >5) and good sleep group (PSQI ≤5). Subjects were also assessed with spirometry, 6-min walk distance (6MWD), oxygen saturation (SP O2 ), the Epworth Sleepiness Scale, Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, COPD Assessment Test (CAT), Modified Medical Research Council dyspnea scale and quadriceps muscle function. RESULTS: Poor sleep was present in 43.69% of the patients with COPD. Subjects with poor sleep had shorter 6MWD (t = -3.588, P < 0.001), greater age (t = 2.519, P = 0.013), worse quality of life (t = 5.487, P < 0.001) and more depression (t = 6.576, P < 0.001) or anxiety (t = 4.245, P < 0.001) symptoms. 6MWD showed significant negative correlations with the PSQI global score (r = -0.373, P < 0.001). Multiple stepwise regresion analysis showed that PSQI global score was an independent psychological predictor of 6MWD, and 6MWD was the only physical predictor of PSQI total score in patients with COPD. CONCLUSION: There is a close relationship between sleep quality and functional exercise capacity in patients with COPD.

[Inspiratory muscle training followed by non-invasive positive pressure ventilation in patients with severe chronic obstructive pulmonary disease: a randomized controlled trial].

OBJECTIVE: To investigate the effects of inspiratory muscle training followed by non-invasive positive pressure ventilation in patients with severe chronic obstructive pulmonary disease (COPD). METHODS: This investigator-initiated randomized, controlled trial recruited 88 patients with stable GOLD stage IV COPD, who were randomized into 4 equal groups to continue oxygen therapy (control group) or to receive inspiratory muscle training followed by non-invasive positive pressure ventilation (IMT-NPPV group), inspiratory muscle training only (IMT group), or noninvasive positive pressure ventilation only (NPPV group) for at least 8 weeks. The outcomes of the patients were assessed including the quality of life (SRI scores), maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), dyspnea (MRC scores), 6-min walking distance (6MWD) and lung function. RESULTS: s Compared to baseline values, SRI scores, 6MWT and MRC scores increased significantly after 8 weeks in IMT-NPPV, IMT and NPPV groups, and the improvements were significantly greater in IMT-NPPV group than in IMT and NPPV groups (P<0.05 for all). In IMT-NPPV and IMT groups, MIP and MEP increased significantly after the training (P<0.05), and the improvement was more prominent in IMT-NPPV group (P<0.05). No significant changes were found in pulmonary functions in the groups after 8 weeks of treatment (P>0.05). CONCLUSION: Inspiratory muscle training followed by non-invasive positive pressure ventilation, compared with inspiratory muscle training or non-invasive positive pressure ventilation alone, can better enhance the quality of life, strengthen the respiratory muscles, improve exercise tolerance and relieve the dyspnea in patients with COPD.