Randomized trial of non-invasive ventilation combined with exercise training in patients with chronic hypercapnic failure due to chronic obstructive pulmonary disease

Home noninvasive ventilation in severe COPD: in whom does it work and how?

Background

Not all hypercapnic COPD patients benefit from home noninvasive ventilation (NIV), and mechanisms through which NIV improves clinical outcomes remain uncertain. We aimed to identify "responders" to home NIV, denoted by a beneficial effect of NIV on arterial partial pressure of carbon dioxide (PaCO2), health-related quality of life (HRQoL) and survival, and investigated whether NIV achieves its beneficial effect through an improved PaCO2.

Methods

We used individual patient data from previous published trials collated for a systematic review. Linear mixed-effect models were conducted to compare the effect of NIV on PaCO2, HRQoL and survival, within subgroups defined by patient and treatment characteristics. Secondly, we conducted a causal mediation analysis to investigate whether the effect of NIV is mediated by a change in PaCO2.

Findings

Data of 1142 participants from 16 studies were used. Participants treated with lower pressure support (<14 versus ≥14 cmH2O) and with lower adherence (<5 versus ≥5 h·day-1) had less improvement in PaCO2 (mean difference (MD) -0.30 kPa, p<0.001 and -0.29 kPa, p<0.001, respectively) and HRQoL (standardised MD 0.10, p=0.002 and 0.11, p=0.02, respectively), but this effect did not persist to survival. PaCO2 improved more in patients with severe dyspnoea (MD -0.30, p=0.02), and HRQoL improved only in participants with fewer than three exacerbations (standardised MD 0.52, p=0.03). The results of the mediation analysis showed that the effect on HRQoL is mediated partially (23%) by a change in PaCO2.

Interpretation

With greater pressure support and better daily NIV usage, a larger improvement in PaCO2 and HRQoL is achieved. Importantly, we demonstrated that the beneficial effect of home NIV on HRQoL is only partially mediated through a reduction in diurnal PaCO2.

Indications and evidence for domiciliary noninvasive ventilation

INTRODUCTION

Home noninvasive ventilation (HNIV) has expanded globally, with a greater evidence base for its use. HNIV improves multiple patient related outcomes in patients with chronic hypercapnic respiratory failure. Obesity hypoventilation syndrome (OHS) is rapidly taking over as the primary indication for HNIV and COPD patients who overlap with obstructive sleep apnea hypoventilation syndromes (OSAHS) and are increasingly recognized but add to the complexity of HNIV prescribing. Optimal settings vary for differing diseases, with higher inspiratory pressures often required in those with OHS and COPD, yet which settings translate into greatest patient benefit remains unknown.

AREAS COVERED

We cover the evidence base underpinning the common indications for HNIV in COPD, OHS, neuromuscular disease (NMD), and chest wall disease (CWD) and highlight common HNIV modes used.

EXPERT OPINION

Active screening for nocturnal hypoventilation in OHS and COPD may be important to guide earlier ventilation. Further research on which HNIV modalities best improve patient related outcomes and the right time for initiation in different patient phenotypes is rapidly needed. Worldwide, clinical research trials should aim to bridge the gap by reporting on patient-related outcomes and cost effectiveness in real-world populations to best understand the true benefit of HNIV amongst heterogenous patient populations.

Home ventilation for patients with end-stage chronic obstructive pulmonary disease

PURPOSE OF THE REVIEW

The number of patients with end-stage chronic obstructive pulmonary disease (COPD) treated with chronic non-invasive ventilation (NIV) has greatly increased. In this review, the authors summarize the evidence for nocturnal NIV and NIV during exercise. The authors discuss the multidisciplinary and advanced care of patients with end-stage COPD treated with NIV.

RECENT FINDINGS

Nocturnal NIV improves gas exchange, health-related quality of life and survival in stable hypercapnic COPD patients. Improvements in care delivery have been achieved by relocating care from the hospital to home based; home initiation of chronic NIV is feasible, non-inferior regarding efficacy and cost-effective compared to in-hospital initiation. However, the effect of NIV on symptoms is variable, and applying optimal NIV for end-stage COPD is complex. While exercise-induced dyspnoea is a prominent complaint in end-stage COPD, nocturnal NIV will not change this. However, NIV applied solely during exercise might improve exercise tolerance and dyspnoea. While chronic NIV is often a long-standing treatment, patient expectations should be discussed early and be managed continuously during the treatment. Further, integration of advance care planning requires a multidisciplinary approach.

SUMMARY

Although chronic NIV is an effective treatment in end-stage COPD with persistent hypercapnia, there are still important questions that need to be answered to improve care of these severely ill patients.

Acute effects of NIV on peripheral muscle function and aerobic performance in patients with chronic obstructive pulmonary disease: a pilot study

Background

Non-invasive ventilation (NIV) reduces respiratory load and demands on peripheral muscles.

Methods

This study aims to evaluate the acute effects of bi-level NIV on peripheral muscle function during isokinetic exercise and aerobic performance in chronic obstructive pulmonary disease (COPD) patients. This is a pilot crossover study performed with a non-probabilistic sample of 14 moderate to very severe COPD patients. Procedures carried out in two days. Dyspnea, quality of life, lung function, respiratory muscle strength, functional capacity (6-min walk test—6MWT), and isokinetic assessment of the quadriceps were assessed. Blood samples (lactate, lactate dehydrogenase, and creatine kinase concentration) were also collected. Right after, NIV was performed for 30 min (bi-level or placebo, according to randomization) followed by new blood sample collection, 6MWT, and isokinetic dynamometer tests. Before and after evaluations, the subjective perception of dyspnea and fatigue in the lower limbs was quantified. After a wash-out period of seven days, participants returned, and all assessments were performed again.

Results

NIV showed improvements in perceived exertion and dyspnea after isokinetic exercise (p < 0.02 and p < 0.05, respectively).

Conclusions

NIV improves the perception of dyspnea and fatigue during the isokinetic exercise.

Domiciliary noninvasive ventilation for chronic respiratory diseases

Patients with chronic respiratory diseases, including chronic obstructive pulmonary disease (COPD), neuromuscular diseases, kyphoscoliosis and obstructive sleep apnoea-obesity hypoventilation syndrome (OSA-OHS), are at a higher risk of decompensation in the form of hypercapnic respiratory failure leading to intensive care unit (ICU) admission and increased mortality. This article reviews the evidence of role of domiciliary noninvasive ventilation (NIV) in patients with diseases with chronic ventilatory failure, including the mechanism of the effect of (NIV).

Hypercapnia in COPD: Causes, Consequences, and Therapy

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder that may lead to gas exchange abnormalities, including hypercapnia. Chronic hypercapnia is an independent risk factor of mortality in COPD, leading to epithelial dysfunction and impaired lung immunity. Moreover, chronic hypercapnia affects the cardiovascular physiology, increases the risk of cardiovascular morbidity and mortality, and promotes muscle wasting and musculoskeletal abnormalities. Noninvasive ventilation is a widely used technique to remove carbon dioxide, and several studies have investigated its role in COPD. In the present review, we aim to summarize the causes and effects of chronic hypercapnia in COPD. Furthermore, we discuss the use of domiciliary noninvasive ventilation as a treatment option for hypercapnia while highlighting the controversies within the evidence. Finally, we provide some insightful clinical recommendations and draw attention to possible future research areas.

Chronic non-invasive ventilation for chronic obstructive pulmonary disease

BACKGROUND

Chronic non-invasive ventilation (NIV) is increasingly being used to treat people with COPD who have respiratory failure, but the evidence supporting this treatment has been conflicting.

OBJECTIVES

To assess the effects of chronic non-invasive ventilation at home via a facial mask in people with COPD, using a pooled analysis of IPD and meta-analysis.

SEARCH METHODS

We searched the Cochrane Airways Register of Trials, MEDLINE, Embase, PsycINFO, CINAHL, AMED, proceedings of respiratory conferences, clinical trial registries and bibliographies of relevant studies. We conducted the latest search on 21 December 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing chronic NIV for at least five hours per night for three consecutive weeks or more (in addition to standard care) versus standard care alone, in people with COPD. Studies investigating people initiated on NIV in a stable phase and studies investigating NIV commenced after a severe COPD exacerbation were eligible, but we reported and analysed them separately. The primary outcomes were arterial blood gases, health-related quality of life (HRQL), exercise capacity (stable COPD) and admission-free survival (post-exacerbation COPD). Secondary outcomes for both populations were: lung function, COPD exacerbations and admissions, and all-cause mortality. For stable COPD, we also reported respiratory muscle strength, dyspnoea and sleep efficiency.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. After inclusion of a study, we requested the IPD. We analysed continuous and time-to-event data using linear- and cox-regression mixed-effect models with a random effect on study level. We analysed dichotomous IPD using generalised estimating equations. We adjusted all models for age and sex. We assessed changes in outcomes after three and 12 months.  We also conducted a meta-analysis on aggregated trial data.

MAIN RESULTS

We included 14 new RCTs in this review update, in addition to the seven previously included. Seventeen studies investigated chronic NIV in stable COPD and four studies investigated chronic NIV commenced after a severe COPD exacerbation. Three studies compared NIV to sham continuous positive airway pressure (2 to 4 cmH₂O). Seven studies used a nasal mask, one study used an oronasal mask and eight studies used both interfaces. Five studies did not report the interface. The majority of trials (20/21) were at high risk of performance bias due to an unblinded design. We considered 11 studies to have a low risk of selection bias and 13 to have a low risk of attrition bias. We collected and analysed the IPD from 13 stable COPD studies (n = 778, 68% of the participants included) and from three post-exacerbation studies (n = 364, 96% of the participants included). In the stable COPD group, NIV probably results in a minor benefit on the arterial partial pressure of oxygen (PaO₂) after three months (adjusted mean difference (AMD) 0.27 kPa, 95% CI 0.04 to 0.49; 9 studies, 271 participants; moderate-certainty evidence), but there was little to no benefit at 12 months (AMD 0.09 kPa, 95% CI -0.23 to 0.42; 3 studies, 171 participants; low-certainty evidence). The arterial partial pressure of carbon dioxide (PaCO₂) was reduced in participants allocated to NIV after three months (AMD -0.61 kPa, 95% CI -0.77 to -0.45; 11 studies, 475 participants; high-certainty evidence) and persisted up to 12 months (AMD -0.42 kPa, 95% CI -0.68 to -0.16; 4 studies, 232 participants; high-certainty evidence).  Exercise capacity was measured with the 6-minute walking distance (minimal clinical important difference: 26 m). There was no clinically relevant effect of NIV on exercise capacity (3 months: AMD 15.5 m, 95% CI -0.8 to 31.7; 8 studies, 330 participants; low-certainty evidence; 12 months: AMD 26.4 m, 95% CI -7.6 to 60.5; 3 studies, 134 participants; very low-certainty evidence). HRQL was measured with the Severe Respiratory Insufficiency and the St. Georges's Respiratory Questionnaire and may be improved by NIV, but only after three months (3 months: standardised mean difference (SMD) 0.39, 95% CI 0.15 to 0.62; 5 studies, 259 participants; very low-certainty evidence; 12 months: SMD 0.15, 95% CI -0.13 to 0.43; 4 studies, 200 participants; very low-certainty evidence). Lastly, the risk for all-cause mortality is likely reduced by NIV (adjusted hazard ratio (AHR) 0.75, 95% CI 0.58 to 0.97; 3 studies, 405 participants; moderate-certainty evidence). In the post-exacerbation COPD group, there was little to no benefit on the PaO₂ after three months, but there may be a slight decrease after 12 months (3 months: AMD -0.10 kPa, 95% CI -0.65 to 0.45; 3 studies, 234 participants; low-certainty evidence; 12 months: -0.27 kPa, 95% CI -0.86 to 0.32, 3 studies; 170 participants; low-certainty evidence). The PaCO₂ was reduced by NIV at both three months (AMD -0.40 kPa, 95% CI -0.70 to -0.09; 3 studies, 241 participants; moderate-certainty evidence) and 12 months (AMD -0.52 kPa, 95% CI -0.87 to -0.18; 3 studies, 175 participants; high-certainty evidence). NIV may have little to no benefit on HRQL (3 months: SMD 0.25, 95% CI -0.01 to 0.51; 2 studies, 219 participants; very low-certainty evidence; 12 months: SMD 0.25, 95% -0.06 to 0.55; 2 studies, 164 participants; very low-certainty evidence). Admission-free survival seems improved with NIV (AHR 0.71, 95% CI 0.54 to 0.94; 2 studies, 317 participants; low-certainty evidence), but the risk for all-cause mortality does not seem to improve (AHR 0.97, 95% CI 0.74 to 1.28; 2 studies, 317 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Regardless of the timing of initiation, chronic NIV improves daytime hypercapnia. In addition, in stable COPD, survival seems to be improved and there might be a short term HRQL benefit. In people with persistent hypercapnia after a COPD exacerbation, chronic NIV might prolong admission-free survival without a beneficial effect on HRQL. In stable COPD, future RCTs comparing NIV to a control group receiving standard care might no longer be warranted, but research should focus on identifying participant characteristics that would define treatment success. Furthermore, the optimal timing for initiation of NIV after a severe COPD exacerbation is still unknown.

Long-term home non-invasive ventilation in chronic hypercapnic chronic obstructive pulmonary disease patients: Real-world impact on lung function, acute exacerbations and survival

INTRODUCTION

Although long-term home non-invasive ventilation (H-NIV) has been used among chronic hypercapnic COPD patients, its clinical benefit is still on debate. We aim to assess the impact of H-NIV in chronic hypercapnic COPD patients.

METHODS

COPD patients who initiated H-NIV between January 2010 and December 2017 were included. Patients with concomitant respiratory disorders were excluded. Acute exacerbation (AE) before and 2 years after H-NIV initiation was assessed as main outcome. Secondary outcomes included lung function and gas exchange parameters. Survival since H-NIV initiation was determined, and factors related with survival were explored.

RESULTS

Seventy-two patients were enrolled. A decrease in partial pressure of carbon dioxide (PaCO₂ ) in arterial blood (p < 0.001) and an improvement of partial pressure of oxygen (PaO₂ ) (p < 0.001) were achieved using a high-intensity H-NIV. Regarding lung function, residual volume (RV) reduced (p = 0.010) and forced-expiratory volume in 1 s (FEV₁ ) improved (p = 0.043) after H-NIV initiation. No significant differences in 6-min walking test (6MWT) were found. Compared with the year before H-NIV initiation, the number of AE diminished in the first and in the second years of follow-up (p < 0.001). The median survival was 79.0 months (95% confidence interval [CI], 52.9-105.1), and the covered distance in 6MWT predicted survival (hazard ratio [HR] = 0.026, p = 0.003) in the multivariate analysis.

CONCLUSIONS

High-intensity H-NIV significantly improved FEV1 and hyperinflation, decreased frequency of AEs and led to a remarkable median survival, which was independently predicted by the walking distance in 6MWT.

Feasibility and clinical impact of a portable bi-level ventilation device in patients with severe chronic obstructive pulmonary disease and exertional dyspnea: preliminary results from a clinical series

We explore home use of a portable bi-level ventilation device among patients with severe chronic obstructive pulmonary disease (COPD), and describe changes in the patients' physical activity levels, perceived dyspnea, anxiety and depression, as well as their satisfaction with the device, after one month of use.

METHODS

Forty patients with severe COPD and exertional dyspnea were instructed to use VitaBreath® device (Philips, Respironics) during efforts or activities of daily living for 4 weeks, and agreed to answer questionnaires on anxiety, depression, dyspnea and physical activity.

RESULTS

Twenty-six (65%) patients used the VitaBreath® device for four weeks, while 14 patients (35%) stopped early for various reasons. Among patients who completed the 4-week course, no differences in dyspnea and physical activity were observed between baseline and follow-up (p-values 0.41 and 0.19, respectively). Thirteen (50%) and 15 (57%) patients experienced reduced anxiety and depression, respectively. Patients with greater functional impairment and less autonomy in activities of daily living tended to view the device more positively.

CONCLUSION

Home use of portable bi-level positive-pressure ventilation devices by patients with COPD may alleviate disease-related anxiety and depression, particularly in more severe cases of COPD. Future portable device design should feature adjustable inspiratory/expiratory pressures.

Non-invasive ventilation intervention during exercise training in individuals with chronic obstructive pulmonary disease: A systematic review and meta-analysis

OBJECTIVE

evidence is inconsistent for the effect of non-invasive ventilation (NIV) for individuals with chronic obstructive pulmonary disease (COPD) during exercise training. This review aimed to determine the effect of NIV in COPD individuals during exercise training on exercise capacity, quality of life, functional performance and symptoms.

MATERIAL AND METHODS

we searched for studies evaluating the effect of NIV on COPD individuals during exercise training published until May 2020 in 6 electronic databases (PubMed, Embase, Cochrane Library, Web of Science, clinical trial registers and Wanfang). The included studies were appraised with the Cochrane Risk of Bias tool and Downs and Black criteria. The primary outcomes were improvement in 6-min walking distance and quality of life. Mean difference (MD) or standardized mean difference (SMD) with 95% confidence intervals (CIs) was calculated.

RESULTS

among 855 identified articles, reports for 15 studies with heterogeneous populations were eligible, with 520 individuals: 257 in the NIV group and 263 in the control group. Across studies, NIV intervention during exercise training affected exercise performance (6-min walking distance: SMD: 0.33, 95% CI: 0.06; 0.59, P=0.02; quality of life: SMD: -0.77, 95% CI: -1.01; -0.53, P<0.001). In the analysis of dyspnea, pooled estimates demonstrated improvement in the NIV versus control group. NIV intervention was also better than exercise alone in ameliorating oxygen saturation, PaO2, PaCO2, blood lactate level and breath rate. The groups did not differ in duration of exercise, BODE index, minute ventilation, heart rate and systolic blood pressure.

CONCLUSIONS

our review suggests that NIV is a relevant adjuvant for exercise training in COPD individuals because the intervention could improve exercise performance and quality of life. The current results also demonstrate the importance of further investigations of higher methodological quality to assess the effect on exercise capacity and quality of life.

NIV Is not Adequate for High Intensity Endurance Exercise in COPD

Noninvasive ventilation (NIV) during exercise has been suggested to sustain higher training intensity but the type of NIV interface, patient-ventilator asynchronies (PVA) or technological limitation of the ventilator may interfere with exercise. We assessed whether these parameters affect endurance exercise capacity in severe COPD patients. In total, 21 patients with severe COPD not eligible to home NIV performed three constant workload tests. The first test was carried out on spontaneous breathing (SB) and the following ones with NIV and a nasal or oronasal mask in a randomized order. PVA and indicators of ventilator performance were assessed through a comprehensive analysis of the flow pressure tracing raw data from the ventilator. The time limit was significantly reduced with both masks (406 s (197–666), 240 s (131–385) and 189 s (115–545), p < 0.01 for tests in SB, with oronasal and nasal mask, respectively). There were few PVA with an oronasal mask (median: 3.4% (1.7–5.2)) but the ventilator reached its maximal generating capacity (median flowmax: 208.0 L/s (189.5–224.8) while inspiratory pressure dropped throughout exercise (from 10.1 (9.4–11.4) to 8.8 cmH2O (8.6–10.8), p < 0.01). PVA were more frequent with nasal mask (median: 12.8% (3.2–31.6), p < 0.01). Particularly, the proportion of patients with ineffective efforts > 10% was significantly higher with nasal interface (0% versus 33.3%, p < 0.01). NIV did not effectively improve endurance capacity in COPD patients not acclimated to home NIV. This was due to a technological limitation of the ventilator for the oronasal mask and the consequence either of an insufficient pressure support or a technological limitation for the nasal mask.

Association of Home Noninvasive Positive Pressure Ventilation With Clinical Outcomes in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis

IMPORTANCE

The association of home noninvasive positive pressure ventilation (NIPPV) with outcomes in chronic obstructive pulmonary disease (COPD) and hypercapnia is uncertain.

OBJECTIVE

To evaluate the association of home NIPPV via bilevel positive airway pressure (BPAP) devices and noninvasive home mechanical ventilator (HMV) devices with clinical outcomes and adverse events in patients with COPD and hypercapnia.

DATA SOURCES

Search of MEDLINE, EMBASE, SCOPUS, Cochrane Central Registrar of Controlled Trials, Cochrane Database of Systematic Reviews, National Guideline Clearinghouse, and Scopus for English-language articles published from January 1, 1995, to November 6, 2019.

STUDY SELECTION

Randomized clinical trials (RCTs) and comparative observational studies that enrolled adults with COPD with hypercapnia who used home NIPPV for more than 1 month were included.

DATA EXTRACTION AND SYNTHESIS

Data extraction was completed by independent pairs of reviewers. Risk of bias was evaluated using the Cochrane Collaboration risk of bias tool for RCTs and select items from the Newcastle-Ottawa Scale for nonrandomized studies.

MAIN OUTCOMES AND MEASURES

Primary outcomes were mortality, all-cause hospital admissions, need for intubation, and quality of life at the longest follow-up.

RESULTS

A total of 21 RCTs and 12 observational studies evaluating 51 085 patients (mean [SD] age, 65.7 [2.1] years; 43% women) were included, among whom there were 434 deaths and 27 patients who underwent intubation. BPAP compared with no device was significantly associated with lower risk of mortality (22.31% vs 28.57%; risk difference [RD], -5.53% [95% CI, -10.29% to -0.76%]; odds ratio [OR], 0.66 [95% CI, 0.51-0.87]; P = .003; 13 studies; 1423 patients; strength of evidence [SOE], moderate), fewer patients with all-cause hospital admissions (39.74% vs 75.00%; RD, -35.26% [95% CI, -49.39% to -21.12%]; OR, 0.22 [95% CI, 0.11-0.43]; P < .001; 1 study; 166 patients; SOE, low), and lower need for intubation (5.34% vs 14.71%; RD, -8.02% [95% CI, -14.77% to -1.28%]; OR, 0.34 [95% CI, 0.14-0.83]; P = .02; 3 studies; 267 patients; SOE, moderate). There was no significant difference in the total number of all-cause hospital admissions (rate ratio, 0.91 [95% CI, 0.71-1.17]; P = .47; 5 studies; 326 patients; SOE, low) or quality of life (standardized mean difference, 0.16 [95% CI, -0.06 to 0.39]; P = .15; 9 studies; 833 patients; SOE, insufficient). Noninvasive HMV use compared with no device was significantly associated with fewer all-cause hospital admissions (rate ratio, 0.50 [95% CI, 0.35-0.71]; P < .001; 1 study; 93 patients; SOE, low), but not mortality (21.84% vs 34.09%; RD, -11.99% [95% CI, -24.77% to 0.79%]; OR, 0.56 [95% CI, 0.29-1.08]; P = .49; 2 studies; 175 patients; SOE, insufficient). There was no statistically significant difference in the total number of adverse events in patients using NIPPV compared with no device (0.18 vs 0.17 per patient; P = .84; 6 studies; 414 patients).

CONCLUSIONS AND RELEVANCE

In this meta-analysis of patients with COPD and hypercapnia, home BPAP, compared with no device, was associated with lower risk of mortality, all-cause hospital admission, and intubation, but no significant difference in quality of life. Noninvasive HMV, compared with no device, was significantly associated with lower risk of hospital admission, but there was no significant difference in mortality risk. However, the evidence was low to moderate in quality, the evidence on quality of life was insufficient, and the analyses for some outcomes were based on small numbers of studies.

Exercise Training in Patients with Chronic Respiratory Diseases: Are Cardiovascular Comorbidities and Outcomes Taken into Account?-A Systematic Review

Patients with chronic obstructive pulmonary disease (COPD), asthma and interstitial lung diseases (ILD) frequently suffer from cardiovascular comorbidities (CVC). Exercise training is a cornerstone intervention for the management of these conditions, however recommendations on tailoring programmes to patients suffering from respiratory diseases and CVC are scarce. This systematic review aimed to identify the eligibility criteria used to select patients with COPD, asthma or ILD and CVC to exercise programmes; assess the impact of exercise on cardiovascular outcomes; and identify how exercise programmes were tailored to CVC. PubMed, Scopus, Web of Science and Cochrane were searched. Three reviewers extracted the data and two reviewers independently assessed the quality of studies with the Quality Assessment Tool for Quantitative Studies. MetaXL 5.3 was used to calculate the individual and pooled effect sizes (ES). Most studies (58.9%) excluded patients with both stable and unstable CVC. In total, 26/42 studies reported cardiovascular outcomes. Resting heart rate was the most reported outcome measure (n = 13) and a small statistically significant effect (ES = -0.23) of exercise training on resting heart rate of patients with COPD was found. No specific adjustments to exercise prescription were described. Few studies have included patients with CVC. There was a lack of tailoring of exercise programmes and limited effects were found. Future studies should explore the effect of tailored exercise programmes on relevant outcome measures in respiratory patients with CVC.

European Respiratory Society guidelines on long-term home non-invasive ventilation for management of COPD

Background

While the role of acute non-invasive ventilation (NIV) has been shown to improve outcome in acute life-threatening hypercapnic respiratory failure in COPD, the evidence of clinical efficacy of long-term home NIV (LTH-NIV) for management of COPD is less. This document provides evidence-based recommendations for the clinical application of LTH-NIV in chronic hypercapnic COPD patients.

Materials and methods

The European Respiratory Society task force committee was composed of clinicians, methodologists and experts in the field of LTH-NIV. The committee developed recommendations based on the GRADE (Grading, Recommendation, Assessment, Development and Evaluation) methodology. The GRADE Evidence to Decision framework was used to formulate recommendations. A number of topics were addressed under a narrative format which provides a useful context for clinicians and patients.

Results

The task force committee delivered conditional recommendations for four actionable PICO (target population-intervention-comparator-outcome) questions, 1) suggesting for the use of LTH-NIV in stable hypercapnic COPD; 2) suggesting for the use of LTH-NIV in COPD patients following a COPD exacerbation requiring acute NIV 3) suggesting for the use of NIV settings targeting a reduction in carbon dioxide and 4) suggesting for using fixed pressure support as first choice ventilator mode.

Conclusions

Managing hypercapnia may be an important intervention for improving the health outcome of COPD patients with chronic respiratory failure. The task force conditionally supports the application of LTH-NIV to improve health outcome by targeting a reduction in carbon dioxide in COPD patients with persistent hypercapnic respiratory failure. These recommendations should be applied in clinical practice by practitioners that routinely care for chronic hypercapnic COPD patients.

Non-Invasive Ventilation as an Adjunct to Exercise Training in Chronic Ventilatory Failure: A Narrative Review

BACKGROUND

Chronic ventilatory failure (CVF) may be associated with reduced exercise capacity. Long-term non-invasive ventilation (NIV) may reduce patients' symptoms, improve health-related quality of life and reduce mortality and hospitalisations. There is an increasing use of NIV during exercise training with the purpose to train patients at intensity levels higher than allowed by their pathophysiological conditions.

OBJECTIVE

This narrative review describes the possibility to train patients with CVF and NIV use as a tool to increase the benefits of exercise training.

METHODS

We searched papers published between 1985 and 2018 in (or with the summary in) English language in PubMed and Scopus databases using the keywords "chronic respiratory failure AND exercise," "non invasive ventilation AND exercise," "pulmonary rehabilitation" and "exercise training."

RESULTS

Exercise training is feasible and effective also in patients with CVF. Assisted ventilation can improve exercise tolerance in different clinical conditions. In patients under long-term home ventilatory support, NIV administered also during walking results in improved oxygenation, decreased dyspnoea and increased walking distance. Continuous positive airway pressure and different modalities of assisted ventilation have been delivered through different interfaces during exercise training programmes. Patients with CVF on long-term NIV may benefit from exercising with the same ventilators, interfaces and settings as used at home.

CONCLUSION

We need more randomised clinical trials to investigate the effects of NIV on exercise training in patients with CVF and define organisation and setting.

Update: non-invasive ventilation in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) remains a common cause of morbidity and mortality worldwide. Patients with COPD and respiratory failure, whether acute or chronic have a poorer prognosis than patients without respiratory failure. Non-invasive ventilation (NIV) has been shown to be a useful tool in both the acute hospital and chronic home care setting. NIV has been well established as the gold standard therapy for acute decompensated respiratory failure complicating an acute exacerbation of COPD with reduced mortality and intubation rates compared to standard therapy. However, NIV has been increasingly used in other clinical situations such as for weaning from invasive ventilation and to palliate symptoms in patients not suitable for invasive ventilation. The equivocal evidence for the use of NIV in chronic hypercapnic respiratory failure complicating COPD has recently been challenged with data now supporting a role for therapy in selected subgroups of patients. Finally the review will discuss the emerging role of high flow humidified therapy to support or replace NIV in certain clinical situation.

Non-invasive ventilation during cycle exercise training in patients with chronic respiratory failure on long-term ventilatory support: A randomized controlled trial

BACKGROUND AND OBJECTIVE

The role of non-invasive ventilation (NIV) during exercise training (ET) in patients with chronic respiratory failure (CRF) is still unclear. The aim of this study was to test whether NIV during ET had an additional effect in increasing the 6-min walking distance (6MWD) and cycle endurance time compared with ET alone.

METHODS

All patients underwent 20 sessions of cycle training over 3 weeks and were randomly assigned to ET with NIV or ET alone. Outcome measures were 6MWD (primary outcome), incremental and endurance cycle ergometer exercise time, respiratory muscle function, quality of life by the Maugeri Respiratory Failure questionnaire (MRF-28), dyspnoea (Medical Research Council scale) and leg fatigue at rest.

RESULTS

Forty-two patients completed the study. Following training, no significant difference in 6MWD changes were found between groups. Improvement in endurance time was significantly greater in the NIV group compared with the non-NIV training group (754 ± 973 vs 51 ± 406 s, P = 0.0271); dyspnoea improved in both groups, while respiratory muscle function and leg fatigue improved only in the NIV ET group. MRF-28 improved only in the group training without NIV.

CONCLUSION

In CRF patients on long-term NIV and long-term oxygen therapy (LTOT), the addition of NIV to ET sessions resulted in an improvement in endurance time, but not in 6MWD.

The Use of Non-invasive Ventilation during Exercise Training in COPD Patients

Non-invasive ventilation (NIV) is increasingly used in addition to exercise training in patients with chronic obstructive pulmonary disease with the purpose to allow them to train at higher intensities. Different modalities of assisted ventilation have been used with benefits for relief of dyspnoea and increase in exercise capacity. Nevertheless there are some potential problems with the use of NIV in pulmonary rehabilitation programmes. Despite promising results, a generalised use of NIV during exercise training programmes is unlikely to have a role in routine settings. The use of NIV during exercise training as a component of pulmonary rehabilitation should be reserved to individual cases.

Is a pulmonary rehabilitation program effective in COPD patients with chronic hypercapnic failure?

OBJECTIVES

Our study aimed to compare the effectiveness of a pulmonary rehabilitation (PR) program between hypercapnic and normocapnic patients with chronic obstructive pulmonary disease (COPD).

METHODS

Hypercapnic (Group 1) and normocapnic (Group 2) patients with COPD who participated in this study underwent a comprehensive 8-week out-patient PR program.

RESULTS

A total of 122 patients were enrolled in the study; (n:86, n:36 groups 1 and 2, respectively.) After PR, both groups had better symptom scores as well as physical, social and emotional functioning. In addition, the groups had reduced dyspnea, anxiety and depression scores. After PR, the hypercapnic group improved significantly more in exercise capacity (∆6 MWT 50 m. vs 40 m.) compared with normocapnic patients (p=0.044). The hypercapnic group demonstrated a significant reduction in the PaCO2 levels after PR within (p<0.05) and between groups (p<0.0001).

CONCLUSIONS

Given the significant reductions in pCO2 levels and significant increases in exercise capacity and QoL parameters after PR, the patients with chronic hypercapnic failure apparently benefited from the PR.

Update on clinical trials in home mechanical ventilation

Home mechanical ventilation (HMV) is an increasingly common intervention and is initiated for a range of pathological processes, including neuromuscular disease (NMD), chronic obstructive pulmonary disease (COPD) and obesity related respiratory failure. There have been important recent data published in this area, which helps to guide practice by indicating which populations may benefit from this intervention and the optimum method of setting up and controlling sleep disordered breathing. Recent superficially conflicting data has been published regarding HMV in COPD, with a trial in post-exacerbation patients suggesting no benefit, but in stable chronic hypercapnic patients suggesting a clear and sustained mortality benefit. The two studies are critiqued and the potential reasons for the differing results are discussed. Early and small trial data is frequently contradicted with larger randomised controlled trials and this has been the case with diaphragm pacing being shown to be potentially harmful in the latest data, confirming the importance of non-invasive ventilation (NIV) in NMD such as motor neurone disease. Advances in ventilator technology have so far appeared quicker than the clinical data to support their use; although small and often unblinded, the current data suggests equivalence to standard modes of NIV, but with potential comfort benefits that may enhance adherence. The indications for NIV have expanded since its inception, with an effort to treat sleep disordered breathing as a result of chronic heart failure (HF). The SERVE-HF trial has recently demonstrated no clear advantage to this technology and furthermore detected a potentially deleterious effect, with a worsening of all cause and cardiovascular mortality in the treated group compared to controls. The review serves to provide the reader with a critical review of recent advances in the field of sleep disordered breathing and HMV.

Non invasive ventilation as an additional tool for exercise training

Recently, there has been increasing interest in the use of non invasive ventilation (NIV) to increase exercise capacity. In individuals with COPD, NIV during exercise reduces dyspnoea and increases exercise tolerance. Different modalities of mechanical ventilation have been used non-invasively as a tool to increase exercise tolerance in COPD, heart failure and lung and thoracic restrictive diseases. Inspiratory support provides symptomatic benefit by unloading the ventilatory muscles, whereas Continuous Positive Airway Pressure (CPAP) counterbalances the intrinsic positive end-expiratory pressure in COPD patients. Severe stable COPD patients undergoing home nocturnal NIV and daytime exercise training showed some benefits. Furthermore, it has been reported that in chronic hypercapnic COPD under long-term ventilatory support, NIV can also be administered during walking. Despite these results, the role of NIV as a routine component of pulmonary rehabilitation is still to be defined.