Is there a role for airway clearance techniques in chronic obstructive pulmonary disease?

Effects of High Frequency Chest Wall Oscillation (HFCWO) on Clinical Symptoms in COPD

Background

Mucociliary clearance plays a critical role in pulmonary host defense. Abnormal mucociliary clearance contributes to the pathogenesis of pulmonary disorders, including COPD. In bronchiectasis, treatments targeting mucus obstruction in the airways include the use of high frequency chest wall oscillation (HFCWO) therapy. This prospective outcome based study was designed to investigate the changes in symptoms and quality of life (QOL) to measure the effect of adjunctive HFCWO therapy to standard of care therapy for patients with COPD.

Research Question

When HFCWO is indicated and used as intended, will the quality of life for those patients with COPD improve and sustain improvement.

Study Design and Methods

We conducted a prospective, openl-label, observational study in COPD patients without concomitant bronchiectasis. Participants had assessments of QOL at baseline (day 0) and then at 30 and 90 days after initiation of HFCWO therapy. The St. George's Respiratory Questionnaire for COPD Patients (SGRQ-C) was employed and longitudinally followed at each timepoint. Paired t-tests were used to compare means between each time points adjusted for multiple comparisons. A linear mixed model for the analysis of longitudinal data was then constructed to determine the simultaneous contribution of race, gender, ethnicity, time, and selected interactions in the primary outcome of change in SGRQ-C across 0, 30, and 90 days.

Results

The cohort of patients (n=102) demonstrated a significant reduction in the SGRQ-C at 30 and sustained at 90 days compared to baseline. In addition, two component scores of the SGRQ-C questionnaire ("Symptoms" and Impacts") were significantly reduced at 30 and 90 days.

Interpretation

This prospective, observational study demonstrates statistically significant and clinically favorable responses to HFCWO as an adjunctive therapy for patients with a primary diagnosis of COPD without concomitant bronchiectasis. Results of this study inform the design of additional additional studies of HFCWO to prove efficacy inCOPD patients.

Non-Pharmaceutical Techniques for Obstructive Airway Clearance Focusing on the Role of Oscillating Positive Expiratory Pressure (OPEP): A Narrative Review

Mucus secretion in the lungs is a natural process that protects the airways from inhaled insoluble particle accumulation by capture and removal via the mucociliary escalator. Diseases such as cystic fibrosis (CF) and associated bronchiectasis, as well as chronic obstructive pulmonary disease (COPD), result in mucus layer thickening, associated with high viscosity in CF, which can eventually lead to complete airway obstruction. These processes severely impair the delivery of inhaled medications to obstructed regions of the lungs, resulting in poorly controlled disease with associated increased morbidity and mortality. This narrative review article focuses on the use of non-pharmacological airway clearance therapies (ACTs) that promote mechanical movement from the obstructed airway. Particular attention is given to the evolving application of oscillating positive expiratory pressure (OPEP) therapy via a variety of devices. Advice is provided as to the features that appear to be the most effective at mucus mobilization.

Slow chest compression acutely reduces dynamic hyperinflation in people with chronic obstructive pulmonary disease: a randomized cross-over trial

Background: Strategies to minimize dynamic hyperinflation (DH) and dyspnea, such as slow chest compression (SCC), are relevant in people with chronic obstructive pulmonary disease (COPD).Objectives: To analyze the acute effects of SCC after exercise on DH and dyspnea in people with COPD and to identify responders to the technique.Methods: This is a cross-over study with 40 patients. Two six-minute step tests (6MSTs) were performed followed by a one-minute application of SCC (6MST_SCC) or rest (6MST_CONTROL), at random. End-expiratory lung volume (EELV) and dyspnea were assessed. A difference ≥76 ml in ΔEELV between SCC and control characterized the responders.Results: The performance in 6MST_SCC and 6MST_CONTROL were similar. There was a greater reduction in EELV after 6MST_SCC compared to 6MST_CONTROL (124 ± 193 ml vs. 174 ± 183 ml; p = .049), while there was no difference in change in dyspnea between the SCC and control groups. Twenty-one participants were SCC responders and had higher functional residual capacity [FRC: 5.36 ± 1.09 vs. 4.58 ± 0.94; p = .02; cutoff point: 4.56; sensitivity = 76%; specificity = 53%; AUC = 0.71 (95%CI: 0.54 to 0.87); p = .02].Conclusion: SCC applied immediately after exercise reduced DH, but did not reduce dyspnea in people with COPD. The technique is beneficial only for some patients and FRC can help to identify them.

Effectiveness of Continuous Chest Wall Vibration With Concurrent Aerobic Training on Dyspnea and Functional Exercise Capacity in Patients With Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial

OBJECTIVE

To investigate the effects of continuous chest wall vibration with concurrent aerobic training in addition to a 4-week pulmonary rehabilitation program on dyspnea and functional exercise capacity in patients with chronic obstructive pulmonary disease (COPD).

DESIGN

Randomized, single-blind, placebo-controlled trial.

SETTING

The Cardiopulmonary Rehabilitation Unit of a tertiary referral subacute rehabilitation center.

PARTICIPANTS

A sample of 146 consecutive patients with COPD (Global Initiative for Chronic Obstructive Lung Disease II-III-IV) were assessed for eligibility. The final sample of 40 patients (N=40) was randomized into 3 groups (intervention, sham intervention, control).

INTERVENTIONS

All groups carried out 5 sessions per week for 4 weeks of standard pulmonary rehabilitation treatment. The 2 daily 30-minute sessions included aerobic training and resistance training or airway clearance techniques. The intervention group performed the aerobic training with the addition of continuous chest wall vibration applied during cycling, whereas the sham intervention group received continuous chest wall vibration as a placebo during cycling.

MAIN OUTCOME MEASURES

Six-minute walk distance (6MWD) and Barthel Index based on dyspnea (BID).

RESULTS

A total of 36 participants completed the study (69±7 years; forced expiratory volume in 1 second percentage of predicted, 40.15%±15.97%). Intention to treat analysis showed no significant differences between groups for 6MWD and BID. However, the increase in 6MWD was a clinically important difference in the intervention group (42.57±43.87m, P=.003), with a moderate effect size (d=0.58).

CONCLUSIONS

Continuous chest wall vibration with concurrent aerobic training in addition to a standard pulmonary rehabilitation program might improve functional exercise capacity compared with usual care, but there were no effects on dyspnea, respiratory muscle function, or quality of life in patients with COPD.

Physiotherapy management of acute exacerbations of chronic obstructive pulmonary disease

[Holland AE (2014) Physiotherapy management of acute exacerbations of chronic obstructive pulmonary disease.Journal of Physiotherapy60: 181-188].

The effect of positive expiratory pressure (PEP) therapy on symptoms, quality of life and incidence of re-exacerbation in patients with acute exacerbations of chronic obstructive pulmonary disease: a multicentre, randomised controlled trial

BACKGROUND

Positive expiratory pressure (PEP) is a technique used to enhance sputum clearance during acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The impact of PEP therapy during acute exacerbations on clinically important outcomes is not clear. This study sought to determine the effect of PEP therapy on symptoms, quality of life and future exacerbations in patients with AECOPD.

METHODS

90 inpatients (58 men; mean age 68.6 years, FEV(1) 40.8% predicted) with AECOPD and sputum expectoration were randomised to receive usual care (including physical exercise)±PEP therapy. The Breathlessness, Cough and Sputum Scale (BCSS), St George's Respiratory Questionnaire (SGRQ) and BODE index (Body mass index, airflow Obstruction, Dyspnoea, Exercise tolerance) were measured at discharge, 8 weeks and 6 months following discharge, and analysed via linear mixed models. Exacerbations and hospitalisations were recorded using home diaries.

RESULTS

There were no significant between-group differences over time for BCSS score [mean (SE) at discharge 5.2 (0.4) vs 5.0 (0.4) for PEP and control group, respectively; p=0.978] or SGRQ total score [41.6 (2.6) vs 40.8 (2.8) at 8 weeks, p=0.872]. Dyspnoea improved more rapidly in the PEP group over the first 8 weeks (p=0.006), however these benefits were not observed at 6 months. Exacerbations (p=0.986) and hospitalisations (p=0.359) did not differ between groups.

CONCLUSIONS

We found no evidence that PEP therapy during AECOPD improves important short-term or long-term outcomes. There does not appear to be a routine role for PEP therapy in the management of such individuals.

Positive expiratory pressure via mask does not improve ventilation inhomogeneity more than huffing and coughing in individuals with stable chronic obstructive pulmonary disease and chronic sputum expectoration

BACKGROUND

Positive expiratory pressure (PEP) has been used to promote airway clearance in individuals with chronic obstructive pulmonary disease (COPD) for many years; however, its mechanism of action and benefits are unclear. Previous authors have suggested that PEP improves collateral ventilation via changes in lung volumes.

OBJECTIVES

It was the aim of this study to determine whether PEP improves ventilation inhomogeneity more than controlled huffing and coughing in individuals with stable COPD.

METHODS

Twelve participants with COPD (mean forced expiratory volume in 1 s 45% predicted) and chronic sputum expectoration performed PEP therapy (10-20 cm H2O) or controlled huffing and coughing in random order on alternate study days with a 48-hour washout. Measures of acinar and conductive airway ventilation (S(acin), S(cond)), lung volumes, spirometry and sputum wet weight were recorded before, immediately after and 90 min following treatment. Ease of expectoration [visual analogue scale (VAS)] and oxyhaemoglobin saturation were assessed immediately following treatment.

RESULTS

There were no significant differences between the effect of either test condition at any time point for any test parameter. Mean Sacin immediately following PEP and control conditions was 0.465 and 0.438 litre(-1), respectively (p = 0.45 for comparison between conditions) and mean S(cond) was 0.042 and 0.039 litre(-1) (p = 0.55). PEP therapy did not significantly enhance total mean sputum expectoration compared to controlled huffing and coughing (7.06 vs. 6.15 g; p = 0.51) and did not improve ease of expectoration (VAS PEP 4.8 cm vs. control 4.1 cm; p = 0.53).

CONCLUSION

Any therapeutic benefits of PEP in individuals with COPD and chronic sputum expectoration are unlikely to be mediated by improvements in ventilation or lung volumes.

Efficacy of temporary positive expiratory pressure (TPEP) in patients with lung diseases and chronic mucus hypersecretion. The UNIKO® project: a multicentre randomized controlled trial

OBJECTIVE

To evaluate whether temporary positive expiratory pressure provides benefit in patients with lung diseases and chronic hypersecretion.

DESIGN

Single blind multicentre randomized trial.

SETTING

Five Italian rehabilitation centres.

PARTICIPANTS

Ninety-eight patients with chronic obstructive pulmonary disease and/or chronic bronchitis (n=78), or bronchiectasis (n=20), with a peak cough expiratory flow >150 l/min and sputum production >30 ml/day, randomly included into two treatment groups.

INTERVENTIONS

For 10 consecutive days, the active group performed twice a day 20-minute cycles of manually assisted breathing techniques in sequence with the addition of 15 minutes of temporary positive expiratory pressure, while the control group was treated by manually assisted breathing techniques alone.

MEASURES

Within and between group changes of arterial oxygenation index, lung volumes and respiratory muscles strength were recorded at enrolment and after 3 and 10 treatment sessions. Pre-to-post treatment change of sputum volume and bronchial encumbrance (Δ-visual analog scale), sputum density and purulence were compared daily within the study period.

RESULTS

No significant changes were recorded for the oxygenation index, while dynamic lung volumes and respiratory muscle strength significantly (P <0.05) improved in the active group. The group comparison analysis of the pre-to-post change showed that inspiratory capacity was significantly higher in the active than in the control group (+19.5% and +2.2%, P=0.044) at day 10. A greater improvement in Δ-visual analog scale was recorded in the active group at day 3 and 8.

CONCLUSIONS

These preliminary data suggest that temporary positive expiratory pressure improves lung volumes and speeds up the improvement of bronchial encumbrance in patients with lung diseases and hypersecretion.

Evaluation of the effectiveness of manual chest physiotherapy techniques on quality of life at six months post exacerbation of COPD (MATREX): a randomised controlled equivalence trial

BACKGROUND

Manual chest physiotherapy (MCP) techniques involving chest percussion, vibration, and shaking have long been used in the treatment of respiratory conditions. However, methodological limitations in existing research have led to a state of clinical equipoise with respect to this treatment. Thus, for patients hospitalised with an exacerbation of Chronic Obstructive Pulmonary Disease (COPD), clinical preference tends to dictate whether MCP is given to assist with sputum clearance. We standardised the delivery of MCP and assessed its effectiveness on disease-specific quality of life.

METHODS

In this randomised, controlled trial powered for equivalence, 526 patients hospitalised with acute COPD exacerbation were enrolled from four centres in the UK. Patients were allocated to receive MCP plus advice on airway clearance or advice on chest clearance alone. The primary outcome was a COPD specific quality of life measure, the Saint Georges Respiratory Questionnaire (SGRQ) at six months post randomisation. Analyses were by intention to treat (ITT). This study was registered, ISRCTN13825248.

RESULTS

All patients were included in the analyses, of which 372 (71%) provided evaluable data for the primary outcome. An effect size of 0·3 standard deviations in SGRQ score was specified as the threshold for superiority. The ITT analyses showed no significant difference in SGRQ for patients who did, or did not receive MCP (95% CI -0·14 to 0·19).

CONCLUSIONS

These data do not lend support to the routine use of MCP in the management of acute exacerbation of COPD. However, this does not mean that MCP is of no therapeutic value to COPD patients in specific circumstances.

Airway clearance techniques for chronic obstructive pulmonary disease

BACKGROUND

Cough and sputum production are common in chronic obstructive pulmonary disease (COPD) and are associated with adverse clinical outcomes. Airway clearance techniques (ACTs) aim to remove sputum from the lungs, however evidence of their efficacy during acute exacerbations of COPD (AECOPD) or stable disease is unclear.

OBJECTIVES

To assess the safety and efficacy of ACTs for individuals with AECOPD and stable COPD.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials from inception to October 2011, and PEDro in October 2009.

SELECTION CRITERIA

We included randomised parallel trials and randomised cross-over trials which compared an ACT to no treatment, cough or sham ACT in participants with investigator-defined COPD, emphysema or chronic bronchitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and assessed the risk of bias. We analysed data from studies of AECOPD separately from stable COPD, and classified the effects of ACTs as 'immediate' (less than 24 hours), 'short-term' (24 hours to eight weeks) or 'long-term' (greater than eight weeks). One subgroup analysis compared the effects of ACTs that use positive expiratory pressure (PEP) to those that do not.

MAIN RESULTS

Twenty-eight studies on 907 participants were included in the review. Study sample size was generally small (range 5 to 96 people) and overall quality was generally poor due to inadequate blinding and allocation procedures. Meta-analyses were limited by heterogeneity of outcome measurement and inadequate reporting of data.In people experiencing AECOPD, ACT use was associated with small but significant short-term reductions in the need for increased ventilatory assistance (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.05 to 0.85; data from four studies on 171 people), the duration of ventilatory assistance (mean difference (MD) -2.05 days, 95% CI -2.60 to -1.51; mean duration for control groups seven days; data from two studies on 54 people) and hospital length of stay (MD -0.75 days, 95% CI -1.38 to -0.11; mean duration for control groups nine days; one study on 35 people). Data from a limited number of studies revealed no significant long-term benefits of ACTs on the number of exacerbations or hospitalisations, nor any short-term beneficial effect on health-related quality of life (HRQoL) as measured by the St. George's Respiratory Questionnaire (SGRQ) total score (MD -2.30, 95% CI -11.80 to 7.20; one study on 59 people).In people with stable COPD, data from single studies revealed no significant short-term benefit of ACTs on the number of people with exacerbations (OR 3.21, 95% CI 0.12 to 85.20; one study on 30 people), significant short-term improvements in HRQoL as measured by the SGRQ total score (MD -6.10, 95% CI -8.93 to -3.27; one study on 15 people) and a reduced long-term need for respiratory-related hospitalisation (OR 0.27, 95% CI 0.08 to 0.95; one study on 35 participants).The magnitude of effect of PEP-based ACTs on the need for increased ventilatory assistance and hospital length of stay was greater than for non-PEP ACTs, however we found no statistically significant subgroup differences. There was one report of vomiting during treatment with postural drainage and head-down tilt.

AUTHORS' CONCLUSIONS

Evidence from this review indicates that airway clearance techniques are safe for individuals with COPD and confer small beneficial effects on some clinical outcomes. Consideration may be given to the use of airway clearance techniques for patients with COPD in both acute and stable disease, however current studies suggest that the benefits achieved may be small.

Efeitos da pressão positiva expiratória nas vias aéreas sobre a atividade eletromiográfica da musculatura acessória da inspiração em portadores de DPOC

OBJETIVO: Avaliar a atividade eletromiográfica (AE) dos músculos esternocleidomastoideo (ECM) e escaleno durante e após a aplicação de expiratory positive airway pressure (EPAP, pressão positiva expiratória nas vias aéreas) em portadores de DPOC. MÉTODOS: Ensaio clínico simples cego com 13 indivíduos hígidos como controles e 12 pacientes com DPOC estável. No momento basal, foram determinados a AE em respiração espontânea, parâmetros da função pulmonar e a força muscular respiratória. Posteriormente, foi aplicada EPAP de 15 cmH2O com uma máscara facial durante 25 min, com o registro do sinal eletromiográfico dos músculos ECM e escaleno a cada 5 min. Um último registro foi obtido 10 min após a retirada da máscara. RESULTADOS: Observamos que o comportamento da AE dos músculos ECM e escaleno foi semelhante nos controles e pacientes com DPOC (p = 0,716 e p = 0,789, respectivamente). Porém, ao longo da aplicação de EPAP, ambos os músculos mostraram uma tendência ao aumento da AE. Além disso, houve uma redução significativa da AE do ECM entre o momento final e basal (p = 0,034). CONCLUSÕES: A aplicação de EPAP promoveu uma redução significativa da AE do músculo ECM tanto nos controles quanto nos portadores de DPOC estável. Porém, isso não ocorreu em relação à AE do músculo escaleno.

Effect of airway clearance techniques in patients experiencing an acute exacerbation of chronic obstructive pulmonary disease: A systematic review

Answers were sought to the following question: Are techniques, applied predominantly with the aim of clearing secretions from the airways, to patients during an acute exacerbation of chronic obstructive pulmonary disease (AECOPD), safe and effective? A systematic review was undertaken of studies that (i) were either randomized controlled or randomized cross-over trials, (ii) recruited patients during an AECOPD, (iii) reported the results of between-group analyses and (iv) investigated the effect of techniques applied primarily with the aim of clearing secretions from the airways. Studies that examined non-invasive positive pressure ventilation (NIPPV) and early rehabilitation were excluded. Data were extracted pertaining to resting lung function, gas exchange, sputum expectoration, symptoms, NIPPV use and hospital stay. Five studies were included with a mean Physiotherapy Evidence Database (PEDro) score of 4.4 ± 1.1 (range: 3—6). The main findings were that (i) airway clearance techniques did not improve measures of resting lung function or produce any consistent change in measures of gas exchange, (ii) the application of 5 min of continuous chest wall percussion reduced forced expiratory volume in 1 second (FEV 1), (iii) in people with copious secretions, mechanical vibration, and non-oscillating positive expiratory pressure (PEP) mask therapy increased sputum expectoration and (iv) in patients with hypercapnic respiratory failure, intrapulmonary percussive ventilation (IPV) and PEP mask therapy reduced the need for, and duration of, NIPPV, respectively. With the exception of continuous chest wall percussion, airway clearance techniques were safe in patients during an AECOPD. Vibration and non-oscillating PEP facilitated sputum expectoration in patients characterized by copious airway secretions. In patients with respiratory failure, techniques that apply a positive pressure to the airways may reduce either the need for, or duration of, NIPPV and hospital length of stay.