Nocturnal positive-pressure ventilation via nasal mask in patients with severe chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) and COPD-like phenotypes

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease. Historically, two COPD phenotypes have been described: chronic bronchitis and emphysema. Although these phenotypes may provide additional characterization of the pathophysiology of the disease, they are not extensive enough to reflect the heterogeneity of COPD and do not provide granular categorization that indicates specific treatment, perhaps with the exception of adding inhaled glucocorticoids (ICS) in patients with chronic bronchitis. In this review, we describe COPD phenotypes that provide prognostication and/or indicate specific treatment. We also describe COPD-like phenotypes that do not necessarily meet the current diagnostic criteria for COPD but provide additional prognostication and may be the targets for future clinical trials.

A history of home mechanical ventilation: The past, present and future

This state-of-the-art review provides an overview of the history of home mechanical ventilation (HMV), including early descriptions of mechanical ventilation from ancient and Renaissance perspectives and the mass development of ventilators designed for long-term use during the poliomyelitis epidemic. Seminal data from key clinical trials supports the application of HMV in certain patients with chronic obstructive pulmonary disease, neuromuscular disease and obesity-related respiratory failure. Innovative engineering coupled with refined physiological understanding now permits widespread delivery of home mechanical ventilation to a global population, using portable devices with advanced ventilatory modes and telemonitoring capabilities. Exponential growth in digital technology continues, and ongoing research is needed to understand how to harness clinical and physiological data to benefit patients and healthcare services in a clinically- and cost-effective manner.

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.

Caring for patients with advanced COPD: beyond the inhalers…

COPD affects millions of people worldwide. Patients with advanced COPD have a high symptom burden. Breathlessness, cough and fatigue are frequent daily symptoms. Guidelines often focus on pharmacological treatment, especially inhaler therapy, but other approaches in combination with medications offer symptomatic benefit. In this review, we take a multidisciplinary approach with contributions from pulmonary physicians, cardiothoracic surgeons and a physiotherapist. The following areas are addressed: oxygen therapy and noninvasive ventilation (NIV), dyspnoea management, surgical and bronchoscopic options, lung transplantation and palliative care. Oxygen therapy prescribed within guidelines improves mortality in patients with COPD. NIV guidelines offer only low-certainty instruction on the use of this therapy on the basis of the limited available evidence. Dyspnoea management can take place through pulmonary rehabilitation. Specific criteria aid decisions on referral for lung volume reduction treatments through surgical or bronchoscopic approaches. Lung transplantation requires precise disease severity assessment to determine which patients have the most urgent need for lung transplantation and are likely to have the longest survival. The palliative approach runs in parallel with these other treatments, focusing on symptoms and aiming to improve the quality of life of patients and their families facing the problems associated with life-threatening illness. In combination with appropriate medication and an individual approach to symptom management, patients' experiences can be optimised.

Educational aims

To understand the multidisciplinary approach to management of patients with advanced COPD.To recognise the parallel approaches to oxygen, NIV and dyspnoea management with consideration of more interventional options with lung volume reduction therapy or lung transplantation.To understand the high level of symptomatology present in advanced COPD and the relevance of palliative care alongside optimal medical management.

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 noninvasive ventilation in COPD: current evidence and future directions

Introduction: Long-term noninvasive ventilation (NIV) is an established treatment for end-stage COPD patients suffering from chronic hypercapnic respiratory failure. This is reflected by its prominent position in national and international medical guidelines. Areas covered: In recent years, novel developments in technology such as auto-titrating machines and hybrid modes have emerged, and when combined with advances in information and communication technologies, these developments have served to improve the level of NIV-based care. Such progress has largely been instigated by the fact that healthcare systems are now confronted with an increase in the number of patients, which has led to the need for a change in current infrastructures. This article discusses the current practices and recent trends, and offers a glimpse into the future possibilities and requirements associated with this form of ventilation therapy. Expert opinion: Noninvasive ventilation is an established and increasingly used treatment option for patients with chronic hypercapnic COPD and those with persistent hypercapnia following acute hypercapnic lung failure. The main target is to augment alveolar hypoventilation by reducing P_aCO₂ to relieve symptoms. Nevertheless, when dealing with severely impaired patients, it appears necessary to switch the focus to patient-related outcomes such as health-related quality of life.

Respiratory support in COPD patients after acute exacerbation with monitoring the quality of support (Rescue2-monitor): an open-label, prospective randomized, controlled, superiority clinical trial comparing hospital- versus home-based acute non-invasive ventilation for patients with hypercapnic chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is expected to be the 3rd leading cause of death worldwide by 2020. Despite improvements in survival by using acute non-invasive ventilation (NIV) to treat patients with exacerbations of COPD complicated by acute hypercapnic respiratory failure (AHRF), these patients are at high risk of readmission and further life-threatening events, including death. Recent studies suggested that NIV at home can reduce readmissions, but in a small proportion of patients, and with a high level of expertise. Other studies, however, do not show any benefit of home NIV. This could be related to the fact that respiratory failure in patients with stable COPD and their response to mechanical ventilation are influenced by several pathophysiological factors which frequently coexist in the same patient to varying degrees. These pathophysiological factors might influence the success of home NIV in stable COPD, thus long-term NIV specifically adapted to a patient's "phenotype" is likely to improve prognosis, reduce readmission to hospital, and prevent death. In view of this conundrum, Rescue2-monitor (R2M), an open-label, prospective randomized, controlled study performed in patients with hypercapnic COPD post-AHRF, will investigate the impact of the quality of nocturnal NIV on the readmission-free survival. The primary objective is to show that any of 3 home NIV strategies ("rescue," "non-targeted," and "targeted") will improve readmission-free survival in comparison to no-home NIV. The "targeted" group of patients will receive a treatment with personalized (targeted) ventilation settings and extensive monitoring. Furthermore, the influence of comorbidities typical for COPD patients, such as cardiac insufficiency, OSA, or associated asthma, on ventilation outcomes will be taken into consideration and reasons for non-inclusion of patients will be recorded in order to evaluate the percentage of ventilated COPD patients that are screening failures. ClinicalTrials.gov NCT03890224 . Registered on March 26, 2019.

Home mechanical ventilation: back to basics

Over recent decades, the use of home mechanical ventilation (HMV) has steadily increased worldwide, with varying prevalence in different countries. The key indication for HMV is chronic respiratory failure with alveolar hypoventilation (e.g., neuromuscular and chest wall disease, obstructive airway diseases, and obesity-related respiratory failure). Most modern home ventilators are pressure-targeted and have sophisticated modes, alarms, and graphics, thereby facilitating optimization of the ventilator settings. However, different ventilators have different algorithms for tidal volume estimation and leak compensation, and there are also several different circuit configurations. Hence, a basic understanding of the fundamentals of HMV is of paramount importance to healthcare workers taking care of patients with HMV. When choosing a home ventilator, they should take into account many factors, including the current condition and prognosis of the primary disease, the patient’s daily performance status, time (hr/day) needed for ventilator support, family support, and financial costs. In this review, to help readers understand the basic concepts of HMV use, we describe the indications for HMV and the factors that influence successful delivery, including interface, circuits, ventilator accessories, and the ventilator itself.

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.

Is positive airway pressure therapy underutilized in chronic obstructive pulmonary disease patients?

INTRODUCTION

The role of noninvasive positive pressure ventilation (NIPPV) in patients with stable chronic obstructive pulmonary disease (COPD) in the home-setting remains controversial. Despite studies suggesting potential benefits, there is an apparent underutilization of such therapy in patients with stable COPD in a domiciliary setting. Areas covered: The reasons for underutilization in the home-setting are multifactorial, and we provide our perspective on the adequacy of scientific evidence and implementation barriers that may underlie the observed underutilization. In this article, we will discuss continuous PAP, bilevel PAP, and non-invasive positive pressure ventilation using a home ventilator (NIPPV). Expert commentary: Many patients with stable COPD and chronic respiratory failure do not receive NIPPV therapy at home despite supportive scientific evidence. Such underutilization suggests that there are barriers to implementation that include provider knowledge, health services, and payor policies. For patients with stable COPD without chronic respiratory failure, there is inadequate scientific evidence to support domiciliary NIPPV or CPAP therapy. In patients with stable COPD without chronic respiratory failure, studies aimed at identifying patient characteristics that determine the effectiveness of domiciliary NIPPV therapy needs further study. Future implementation and health-policy research with appropriate stakeholders are direly needed to help improve patient outcomes.

Home mechanical ventilation for chronic obstructive pulmonary disease: What next after the HOT-HMV trial?

The benefits of acute non-invasive ventilation to treat acidotic exacerbations of chronic obstructive pulmonary disease (COPD) are well-established. Until recently, the evidence for home mechanical ventilation (HMV) to treat patients with stable COPD had been lacking. This has subsequently been addressed by the application of higher levels of pressure support combined with targeted management of chronic respiratory failure, which demonstrated a reduction in all-cause mortality. Similarly, the previous trial of home oxygen therapy (HOT) and HMV delivered following an acute exacerbation failed to demonstrate an improvement in outcome. With the focus on patients with persistent hypercapnic respiratory failure in the recovery phase following a life-threatening exacerbation combined with targeted reduction in carbon dioxide, HOT and HMV (HOT-HMV) was shown to be clinically effective in reducing the time to readmission or death and cost effective in both the United Kingdom and United States healthcare systems. Future work will need to focus on promoting adherence to home ventilation and novel auto-titrating ventilator modes to facilitate and optimize the set-up of overnight ventilatory support in different target population such as COPD patients with obstructive sleep apnoea and COPD patients with episodic nocturnal hypoventilation.

High-intensity non-invasive ventilation in stable hypercapnic COPD: Evidence of efficacy and practical advice

Patients with end-stage chronic obstructive pulmonary disease (COPD) frequently develop chronic hypercapnic respiratory failure (CHRF), with disabling symptoms and poor survival. The use of long-term nocturnal non-invasive ventilation (NIV) to treat CHRF in COPD has long been subject of debate due to conflicting evidence. However, since the introduction of high-intensity NIV (HI-NIV) in COPD, physiological and clinical benefits have been shown. HI-NIV refers to specific ventilator settings used for NIV aimed at achieving normocapnia or the lowest partial arterial carbon dioxide pressure (PaCO₂ ) values as possible. This review will provide an overview of existing evidence of the efficacy of HI-NIV stable COPD patients with CHRF. Secondly, we will discuss hypotheses underlying NIV benefit in stable hypercapnic COPD, providing insight into better patient selection and hopefully more individually titrated HI-NIV. Finally, we will provide practical advice on how to initiate and follow-up patients on HI-NIV, with special emphasis on monitoring that should be available during the initiation and follow-up of HI-NIV, and will discuss more extended monitoring techniques that could improve HI-NIV treatment in the future.

Hypercapnic COPD patients and NIV at home: is there any benefit? Using the CAT and BODE index in an effort to prove benefits of NIV in these patients

Introduction

The benefits of long-term noninvasive ventilation (NIV) in stable COPD with chronic hypercapnic respiratory failure (CHRF) have been debated for many years due to the conflicting results observed in these patients.

Materials and methods

We investigated the effects of domiciliary NIV in stable hypercapnic COPD patients for a period of 1 year using COPD Assessment Test (CAT), BODE Index, and the number of acute exacerbations. NIV was administered in 57 stable COPD patients with CHRF in the spontaneous/timed mode. Spirometry, 6 minute walk test, Medical Research Council dyspnea scale, arterial blood gases, number of acute exacerbations, BODE Index, and CAT were assessed. Study participants were reassessed in the 1st, 6th, and 12th months after the initial evaluation.

Results

There was a significant improvement in COPD exacerbations (p<0.001), CAT (p<0.001), PO₂ (p<0.001), PCO₂ (p<0.001), and Medical Research Council dyspnea scale (p<0.001) in 1 year of follow-up. BODE Index was improved in the first 6 months (5.8±2.2 vs 4.8±2.4, p<0.001), but the improvement was not maintained.

Conclusion

In conclusion, domiciliary NIV in stable COPD patients with CHRF has beneficial effect on CAT, arterial blood gases, and number of acute exacerbations in a year of NIV use at home. A significant improvement in BODE Index from baseline to 12 months was found in patients aged >70 years, while for those aged <70, the improvement was not maintained after the sixth month.

Noninvasive ventilation in stable hypercapnic COPD: what is the evidence?

Long-term noninvasive ventilation (NIV) to treat chronic hypercapnic respiratory failure is still controversial in severe chronic obstructive pulmonary disease (COPD) patients. However, with the introduction of high-intensity NIV, important benefits from this therapy have also been shown in COPD. In this review, the focus will be on the arguments for long-term NIV at home in patients with COPD. The rise of (high-intensity) NIV in COPD and the randomised controlled trials showing positive effects with this mode of ventilation will be discussed. Finally, the challenges that might be encountered (both in clinical practice and in research) in further optimising this therapy, monitoring and following patients, and selecting the patients who might benefit most will be reviewed.

Home noninvasive ventilatory support for patients with chronic obstructive pulmonary disease: patient selection and perspectives

Long-term or home mechanical noninvasive ventilation (Home-NIV) has become a well-established form of therapy over the last few decades for chronic hypercapnic COPD patients in European countries. However, meta-analyses and clinical guidelines do not recommend Home-NIV for COPD patients on a routine basis. In particular, there is ongoing debate about Home-NIV in chronic hypercapnic COPD regarding the overall effects, the most favorable treatment strategy, the selection of eligible patients, and the time point at which it is prescribed. The current review focuses on specific aspects of patient selection and discusses the various scientific as well as clinical-guided perspectives on Home-NIV in patients suffering from chronic hypercapnic COPD. In addition, special attention will be given to the topic of ventilator settings and interfaces.

AJRCCM: 100-Year Anniversary. Homeward Bound: A Centenary of Home Mechanical Ventilation

The evolution of home mechanical ventilation is an intertwined chronicle of negative and positive pressure modes and their role in managing ventilatory failure in neuromuscular diseases and other chronic disorders. The uptake of noninvasive positive pressure ventilation has resulted in widespread growth in home ventilation internationally and fewer patients being ventilated invasively. As with many applications of domiciliary medical technology, home ventilatory support has either led or run in parallel with acute hospital applications and has been influenced by medical and societal shifts in the approach to chronic care, the creation of community support teams, a preference of recipients to be treated at home, and economic imperatives. This review summarizes the trends and growing evidence base for ventilatory support outside the hospital.

Non invasive ventilation in patients with chronic obstructive pulmonary disease in a hospital and at home

Last two decades, active use of non-invasive ventilation (NIV) has provided a significant improvement in the management of chronic obstructive pulmonary disease (COPD), both in patients with acute exacerbation and in stable patients. Currently, NIV is the first-line treatment for patients with acute exacerbation of COPD and acute hypercapnic respiratory failure. This method of respiratory support is also effective after extubation, as it could facilitate weaning from the ventilator and affects positively prevention and treatment of postextubation respiratory failure. Also, NIV has been successfully used in co-morbidity of COPD and sleep apnea syndrome, COPD and pneumonia, and in early postoperative period after thoracic surgery. NIV can be used in COPD patients with chronic respiratory failure. Long-term NIV at home is more reasonable in patients with daytime hypercapnia. The most effective strategy of respiratory support in COPD is thought to be decrease in the partial pressure of carbon dioxide in the arterial blood, i.e. high-intensity NIV. Currently available portable non-invasive ventilators could improve significantly physical activity of patients with severe COPD.

Impact of High-Intensity-NIV on the heart in stable COPD: a randomised cross-over pilot study

BACKGROUND

Although high-intensity non-invasive ventilation has been shown to improve outcomes in stable COPD, it may adversely affect cardiac performance. Therefore, the aims of the present pilot study were to compare cardiac and pulmonary effects of 6 weeks of low-intensity non-invasive ventilation and 6 weeks of high-intensity non-invasive ventilation in stable COPD patients.

METHODS

In a randomised crossover pilot feasibility study, the change in cardiac output after 6 weeks of each NIV mode compared to baseline was assessed with echocardiography in 14 severe stable COPD patients. Furthermore, CO during NIV, gas exchange, lung function, and health-related quality of life were investigated.

RESULTS

Three patients dropped out: two deteriorated on low-intensity non-invasive ventilation, and one presented with decompensated heart failure while on high-intensity non-invasive ventilation. Eleven patients were included in the analysis. In general, cardiac output and NTproBNP did not change, although individual effects were noticed, depending on the pressures applied and/or the co-existence of heart failure. High-intensity non-invasive ventilation tended to be more effective in improving gas exchange, but both modes improved lung function and the health-related quality of life.

CONCLUSIONS

Long-term non-invasive ventilation with adequate pressure to improve gas exchange and health-related quality of life did not have an overall adverse effect on cardiac performance. Nevertheless, in patients with pre-existing heart failure, the application of very high inspiratory pressures might reduce cardiac output.

TRIAL REGISTRATION

The trial was registered in the Deutsches Register Klinischer Studien (DRKS-ID: DRKS00007977 ).

Respiratory muscle activity and patient-ventilator asynchrony during different settings of noninvasive ventilation in stable hypercapnic COPD: does high inspiratory pressure lead to respiratory muscle unloading?

Introduction

High-intensity noninvasive ventilation (NIV) has been shown to improve outcomes in stable chronic obstructive pulmonary disease patients. However, there is insufficient knowledge about whether with this more controlled ventilatory mode optimal respiratory muscle unloading is provided without an increase in patient–ventilator asynchrony (PVA).

Patients and methods

Ten chronic obstructive pulmonary disease patients on home mechanical ventilation were included. Four different ventilatory settings were investigated in each patient in random order, each for 15 min, varying the inspiratory positive airway pressure and backup breathing frequency. With surface electromyography (EMG), activities of the intercostal muscles, diaphragm, and scalene muscles were determined. Furthermore, pressure tracings were derived simultaneously in order to assess PVA.

Results

Compared to spontaneous breathing, the most pronounced decrease in EMG activity was achieved with the high-pressure settings. Adding a high breathing frequency did reduce EMG activity per breath, while the decrease in EMG activity over 1 min was comparable with the high-pressure, low-frequency setting. With high backup breathing frequencies less breaths were pressure supported (25% vs 97%). PVAs occurred more frequently with the low-frequency settings (P=0.017).

Conclusion

High-intensity NIV might provide optimal unloading of respiratory muscles, without undue increases in PVA.

The effect of domiciliary noninvasive ventilation on clinical outcomes in stable and recently hospitalized patients with COPD: a systematic review and meta-analysis

Introduction

Noninvasive ventilation (NIV) improves survival among patients with hypercapnic respiratory failure in hospital, but evidence for its use in domiciliary settings is limited. A patient’s underlying risk of having an exacerbation may affect any potential benefit that can be gained from domiciliary NIV. This is the first comprehensive systematic review to stratify patients based on a proxy for exacerbation risk: patients in a stable state and those immediately post-exacerbation hospitalization.

Methods

A systematic review of nonrandomized and randomized controlled trials (RCTs) was undertaken in order to compare the relative effectiveness of different types of domiciliary NIV and usual care on hospital admissions, mortality, and health-related quality of life. Standard systematic review methods were used for identifying studies (until September 2014), quality appraisal, and synthesis. Data were presented in forest plots and pooled where appropriate using random-effects meta-analysis.

Results

Thirty-one studies were included. For stable patients, there was no evidence of a survival benefit from NIV (relative risk [RR] 0.88 [0.55, 1.43], I²=60.4%, n=7 RCTs), but there was a possible trend toward fewer hospitalizations (weighted mean difference −0.46 [−1.02, 0.09], I²=59.2%, n=5 RCTs) and improved health-related quality of life. For posthospital patients, survival benefit could not be demonstrated within the three RCTs (RR 0.89 [0.53, 1.49], I²=25.1%), although there was evidence of benefit from four non-RCTs (RR 0.45 [0.32, 0.65], I²=0%). Effects on hospitalizations were inconsistent. Post hoc analyses suggested that NIV-related improvements in hypercapnia were associated with reduced hospital admissions across both populations. Little data were available comparing different types of NIV.

Conclusion

The effectiveness of domiciliary NIV remains uncertain; however, some patients may benefit. Further research is required to identify these patients and to explore the relevance of improvements in hypercapnia in influencing clinical outcomes. Optimum time points for commencing domiciliary NIV and equipment settings need to be established.

The cost-effectiveness of domiciliary non-invasive ventilation in patients with end-stage chronic obstructive pulmonary disease: a systematic review and economic evaluation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic progressive lung disease characterised by non-reversible airflow obstruction. Exacerbations are a key cause of morbidity and mortality and place a considerable burden on health-care systems. While there is evidence that patients benefit from non-invasive ventilation (NIV) in hospital during an acute exacerbation, evidence supporting home use for more stable COPD patients is limited. In the U.K., domiciliary NIV is considered on health economic grounds in patients after three hospital admissions for acute hypercapnic respiratory failure.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of domiciliary NIV by systematic review and economic evaluation.

DATA SOURCES

Bibliographic databases, conference proceedings and ongoing trial registries up to September 2014.

METHODS

Standard systematic review methods were used for identifying relevant clinical effectiveness and cost-effectiveness studies assessing NIV compared with usual care or comparing different types of NIV. Risk of bias was assessed using Cochrane guidelines and relevant economic checklists. Results for primary effectiveness outcomes (mortality, hospitalisations, exacerbations and quality of life) were presented, where possible, in forest plots. A speculative Markov decision model was developed to compare the cost-effectiveness of domiciliary NIV with usual care from a UK perspective for post-hospital and more stable populations separately.

RESULTS

Thirty-one controlled effectiveness studies were identified, which report a variety of outcomes. For stable patients, a modest volume of evidence found no benefit from domiciliary NIV for survival and some non-significant beneficial trends for hospitalisations and quality of life. For post-hospital patients, no benefit from NIV could be shown in terms of survival (from randomised controlled trials) and findings for hospital admissions were inconsistent and based on limited evidence. No conclusions could be drawn regarding potential benefit from different types of NIV. No cost-effectiveness studies of domiciliary NIV were identified. Economic modelling suggested that NIV may be cost-effective in a stable population at a threshold of £30,000 per quality-adjusted life-year (QALY) gained (incremental cost-effectiveness ratio £28,162), but this is associated with uncertainty. In the case of the post-hospital population, results for three separate base cases ranged from usual care dominating to NIV being cost-effective, with an incremental cost-effectiveness ratio of less than £10,000 per QALY gained. All estimates were sensitive to effectiveness estimates, length of benefit from NIV (currently unknown) and some costs. Modelling suggested that reductions in the rate of hospital admissions per patient per year of 24% and 15% in the stable and post-hospital populations, respectively, are required for NIV to be cost-effective.

LIMITATIONS

Evidence on key clinical outcomes remains limited, particularly quality-of-life and long-term (> 2 years) effects. Economic modelling should be viewed as speculative because of uncertainty around effect estimates, baseline risks, length of benefit of NIV and limited quality-of-life/utility data.

CONCLUSIONS

The cost-effectiveness of domiciliary NIV remains uncertain and the findings in this report are sensitive to emergent data. Further evidence is required to identify patients most likely to benefit from domiciliary NIV and to establish optimum time points for starting NIV and equipment settings.

FUTURE WORK RECOMMENDATIONS

The results from this report will need to be re-examined in the light of any new trial results, particularly in terms of reducing the uncertainty in the economic model. Any new randomised controlled trials should consider including a sham non-invasive ventilation arm and/or a higher- and lower-pressure arm. Individual participant data analyses may help to determine whether or not there are any patient characteristics or equipment settings that are predictive of a benefit of NIV and to establish optimum time points for starting (and potentially discounting) NIV.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012003286.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Non-pharmacological treatments for COPD

Chronic obstructive pulmonary disease (COPD) affects roughly 10% of the global population and is growing in prevalence annually. COPD is characterized by progressive non-reversible narrowing of airways mainly due to cigarette smoking. Therapeutic interventions aimed at altering this progressive disease course can largely be grouped into pharmacological or non-pharmacological therapies. The focus of this paper is on the non-pharmacological aspects of COPD management, reviewing the current literature to provide an evidence-based management approach. Non-pharmacological therapies reviewed in this article include the implementation of comprehensive care models utilizing a coordinated multidisciplinary team, tele-monitoring and patient-centred approach to optimize COPD care and improve compliance. Preventing progression of COPD via smoking cessation remains of paramount importance, and newer therapeutic options including electronic cigarettes show promise in small studies as cessation aids. COPD has systemic manifestations that can be ameliorated with the enrollment in pulmonary rehabilitation programmes, which focus on exercise endurance to improve dyspnoea and quality of life. Advanced therapeutics for COPD includes lung volume reduction surgery for a pre-specified cohort and minimally invasive bronchoscopic valves that in recent reviews show promise. Lastly, patients on maximal COPD therapy with progressive disease can be referred for lung transplantation; however, this often requires a highly selected and motivated patient and care team. Survival rates for lung transplantation are improving; thus, this procedure remains a viable option as more expertise and experience are gained.

The role of NIV in chronic hypercapnic COPD following an acute exacerbation: the importance of patient selection?

Recently, clear benefits have been shown from long-term noninvasive ventilation (NIV) in stable chronic obstructive pulmonary disease (COPD) patients with chronic hypercapnic respiratory failure. In our opinion, these benefits are confirmed and nocturnal NIV using sufficiently high inspiratory pressures should be considered in COPD patients with chronic hypercapnic respiratory failure in stable disease, preferably combined with pulmonary rehabilitation. In contrast, clear benefits from (continuing) NIV at home after an exacerbation in patients who remain hypercapnic have not been shown. In this review we will discuss the results of five trials investigating the use of home nocturnal NIV in patients with prolonged hypercapnia after a COPD exacerbation with acute hypercapnic respiratory failure. Although some uncontrolled trials might have shown some benefits of this therapy, the largest randomized controlled trial did not show benefits in terms of hospital readmission or death. However, further studies are necessary to select the patients that optimally benefit, select the right moment to initiate home NIV, select the optimal ventilatory settings, and to choose optimal follow up programmes. Furthermore, there is insufficient knowledge about the optimal ventilatory settings in the post-exacerbation period. Finally, we are not well informed about exact reasons for readmission in patients on NIV, the course of the exacerbation and the treatment instituted. A careful follow up might probably be necessary to prevent deterioration on NIV early.

Update: Non-Invasive Positive Pressure Ventilation in Chronic Respiratory Failure Due to COPD

Long-term non-invasive positive pressure ventilation (NPPV) has widely been accepted to treat chronic hypercapnic respiratory failure arising from different etiologies. Although the survival benefits provided by long-term NPPV in individuals with restrictive thoracic disorders or stable, slowly-progressing neuromuscular disorders are overwhelming, the benefits provided by long-term NPPV in patients with chronic obstructive pulmonary disease (COPD) remain under question, due to a lack of convincing evidence in the literature. In addition, long-term NPPV reportedly failed in the classic trials to improve important physiological parameters such as arterial blood gases, which might serve as an explanation as to why long-term NPPV has not been shown to substantially impact on survival. However, high intensity NPPV (HI-NPPV) using controlled NPPV with the highest possible inspiratory pressures tolerated by the patient has recently been described as a new and promising approach that is well-tolerated and is also capable of improving important physiological parameters such as arterial blood gases and lung function. This clearly contrasts with the conventional approach of low-intensity NPPV (LI-NPPV) that uses considerably lower inspiratory pressures with assisted forms of NPPV. Importantly, HI-NPPV was very recently shown to be superior to LI-NPPV in terms of improved overnight blood gases, and was also better tolerated than LI-NPPV. Furthermore, HI-NPPV, but not LI-NPPV, improved dyspnea, lung function and disease-specific aspects of health-related quality of life. A recent study showed that long-term treatment with NPPV with increased ventilatory pressures that reduced hypercapnia was associated with significant and sustained improvements in overall mortality. Thus, long-term NPPV seems to offer important benefits in this patient group, but the treatment success might be dependent on effective ventilatory strategies.

Complementary home mechanical ventilation techniques. SEPAR Year 2014

This is a review of the different complementary techniques that are useful for optimizing home mechanical ventilation (HMV). Airway clearance is very important in patients with HMV and many patients, particularly those with reduced peak cough flow, require airway clearance (manual or assisted) or assisted cough techniques (manual or mechanical) and suctioning procedures, in addition to ventilation. In the case of invasive HMV, good tracheostomy cannula management is essential for success. HMV patients may have sleep disturbances that must be taken into account. Sleep studies including complete polysomnography or respiratory polygraphy are helpful for identifying patient-ventilator asynchrony. Other techniques, such as bronchoscopy or nutritional support, may be required in patients on HMV, particularly if percutaneous gastrostomy is required. Information on treatment efficacy can be obtained from HMV monitoring, using methods such as pulse oximetry, capnography or the internal programs of the ventilators themselves. Finally, the importance of the patient's subjective perception is reviewed, as this may potentially affect the success of the HMV.

Volume assured versus pressure preset non-invasive ventilation for compensated ventilatory failure in COPD

BACKGROUND

The addition of domiciliary non-invasive ventilation (NIV) to standard therapy in chronic obstructive pulmonary disease (COPD) patients with compensated ventilatory failure (CVF) is reported to have beneficial effects. Compliance with NIV is an important factor. Volume assured NIV (va-NIV) may improve compliance and ventilation during sleep by automatically titrating ventilatory pressures.

METHODS

A prospective single centre, randomised, parallel group trial comparing va-NIV and pressure preset NIV (pp-NIV) in COPD patients with CVF naïve to domiciliary NIV was performed (ISCRTN91892415). The primary outcomes were arterial blood gases, mean overnight oximetry (mSpO2) and compliance after three months. Secondary outcomes included pulmonary function, exercise capacity and health-related quality of life assessment.

RESULTS

Forty patients were randomised in a 1:1 ratio. The va-NIV median target minute ventilation was 8.4 L/min and pp-NIV median inspiratory pressure was 28 cmH2O. There were no significant differences between groups in primary or secondary outcomes after three months. Mean (SD) PaO2 8.7 (1.7) versus 7.9 (1.7) kPa (p = 0.19), PaCO2 6.7 (0.5) versus 7.3 (1.1) kPa (p = 0.1), mSpO2 89.7 (4.2) versus 89.8 (3.9) % (p = 0.95), compliance 5.0 (3.1) versus 4.7 (3.2) hours (p = 0.8) in va-NIV versus pp-NIV respectively. Patients allocated va-NIV spent fewer days in hospital initiating therapy 3.3 (1.6) versus 5.2 (2.8) (p = 0.02). Both groups showed significant improvements in PaCO2 and mSpO2 after three months treatment.

CONCLUSIONS

Domiciliary va-NIV and pp-NIV have similar effects on physiological outcomes in COPD patients with CVF and both are well tolerated.

Current opinions on non-invasive ventilation as a treatment for chronic obstructive pulmonary disease

PURPOSE OF REVIEW

This review examines the current reports, the evidence and the issues surrounding the use of non-invasive ventilation (NIV) for the treatment of chronic obstructive pulmonary disease (COPD) in both the acute and domiciliary setting.

RECENT FINDINGS

With the increasing use of NIV, more recent studies have focused on investigating the outcomes of our current practice. Although overall morbidity and mortality outcomes in the acute setting have improved, patients who initially stabilize but then deteriorate during an acute exacerbation of COPD have a poor prognosis. The focus must be on phenotyping this high-risk group to investigate other potential rescue treatments, including extracorporeal carbon dioxide removal. Indeed, phenotyping appears to favour the obese COPD patient, which may have a protective role in reducing the risk of NIV failure and recurrent hospital admissions. Randomized controlled trial evidence to support the use of NIV in a domiciliary setting as a treatment for COPD is awaited, and until the data from a number of ongoing clinical trials are available, the wide variation in global practice will continue. Increased understanding of patient ventilator asynchrony has improved domiciliary NIV set up, which is expected to enhance the tolerability of NIV, promoting patient adherence.

SUMMARY

NIV is the established standard of care to treat acute hypercapnic exacerbations of COPD postoptimal medical management. NIV as a long-term treatment for COPD remains controversial based on the evidence from the published randomized controlled trials. With increasing experience of NIV therapy, patient outcomes are improving; however, further work is still required to better characterize and target the patients who will most benefit from NIV.

Noninvasive ventilation and lung volume reduction

As parenchymal lung disease in chronic obstructive pulmonary disease becomes increasingly severe there is a diminishing prospect of drug therapies conferring clinically useful benefit. Lung volume reduction surgery is effective in patients with heterogenous upper zone emphysema and reduced exercise tolerance, and is probably underused. Rapid progress is being made in nonsurgical approaches to lung volume reduction, but use outside specialized centers cannot be recommended presently. Noninvasive ventilation given to patients with acute hypercapnic exacerbation of chronic obstructive pulmonary disease reduces mortality and morbidity, but the place of chronic non-invasive ventilatory support remains more controversial.

Nocturnal non-invasive ventilation in COPD patients with prolonged hypercapnia after ventilatory support for acute respiratory failure: a randomised, controlled, parallel-group study

INTRODUCTION

The effectiveness of non-invasive positive pressure ventilation (NIV) in COPD patients with prolonged hypercapnia after ventilatory support for acute respiratory failure (ARF) remains unclear. We investigated if nocturnal NIV in these patients prolongs the time to readmission for respiratory causes or death (primary endpoint) in the following 12 months.

METHODS

201 COPD patients admitted to hospital with ARF and prolonged hypercapnia >48 h after termination of ventilatory support were randomised to NIV or standard treatment. Secondary outcomes were daytime arterial blood gasses, transcutaneous PCO2 during the night, lung function, health-related quality-of-life (HRQL), mood state, daily activities and dyspnoea.

RESULTS

1 year after discharge, 65% versus 64% of patients (NIV vs standard treatment) were readmitted to hospital for respiratory causes or had died; time to event was not different (p=0.85). Daytime PaCO2 was significantly improved in NIV versus standard treatment (PaCO2 0.5 kPa (95% CI 0.04 to 0.90, p=0.03)) as was transcutaneous PCO2 during the night. HRQL showed a trend (p=0.054, Severe Respiratory Insufficiency questionnaire) in favour of NIV. Number of exacerbations, lung function, mood state, daily activity levels or dyspnoea was not significantly different.

DISCUSSIONS

We could not demonstrate an improvement in time to readmission or death by adding NIV for 1 year in patients with prolonged hypercapnia after an episode of NIV for ARF. There is no reason to believe the NIV was not effective since daytime PaCO2 and night-time PCO2 improved. The trend for improvement in HRQL favouring NIV we believe nevertheless should be explored further.

TRIAL REGISTRATION NUMBER

NTR1100.

Noninvasive positive pressure ventilation in subjects with stable COPD: a randomized trial

BACKGROUND

The use of domiciliary noninvasive positive pressure ventilation (NPPV) in stable chronic obstructive pulmonary disease (COPD) with chronic hypercapnic respiratory failure has yielded variable effects on survival, quality of life, and dyspnea. We hypothesized that use of NPPV in stable COPD and partial pressure of carbon dioxide (PaCO2) <52 mmHg might result in improvement in quality of life and dyspnea.

METHODS

Thirty patients with stable COPD (forced expiratory volume in the first second <50% predicted and PaCO2 <52 mmHg) were prospectively randomized to receive domiciliary NPPV (bilevel positive airway pressure, 15/5 cm H2O) or usual therapy for 6 months. Measurements were made at baseline, 6 weeks, 3 months, and 6 months. Primary outcomes were quality of life as assessed by the Chronic Respiratory Disease Questionnaire (CRQ), and dyspnea as measured by the Transitional Dyspnea Index (TDI).

RESULTS

Fifteen subjects in the NPPV arm and 12 controls completed all the study visits. At 6 weeks and 3 months, the NPPV arm showed significant improvement in TDI total score. However, this effect persisted only in the TDI-Task at 6 months (P=0.03). NPPV use was associated with a small improvement in the CRQ-Mastery domain (0.6 versus -0.1, P=0.04). The arterial partial pressure of oxygen (PaO2) in the control arm worsened over the period of the study, whereas it remained stable in the NPPV arm (change -7.2 mmHg versus +2.1 mmHg, respectively, P=0.02).

CONCLUSION

NPPV resulted in a small improvement in quality of life indices in stable COPD patients with PaCO2 <52 mmHg. Future larger studies will clarify the role of NPPV in this stable subgroup of patients with COPD.

Nocturnal non-invasive ventilation for cardio-respiratory disorders in adults

Following the classic 'iron lung' non-invasive negative pressure ventilator, non-invasive positive pressure ventilation (NIPPV), particularly used 'nocturnally' has developed a broad role in both the acute hospital setting and domiciliary long-term use for many cardio-respiratory disorders associated with acute and chronic ventilatory failure. This role is based in part upon the perceived relative ease of application and discontinuation of NIPPV, ability to avoid intubation or tracheostomy and their associated morbidities and availability of increasingly portable pressure and volume cycled NIPPV devices. Nevertheless, the many methodologies necessary for optimal NIPPV use are often underappreciated by health care workers and patients alike. This review focuses on the rationale, practice, and future directions for 'nocturnal' use of non-invasive positive pressure ventilation (nNIV) in cardio-respiratory disorders in adults which are commonly associated with sleep-related apnea, hypoventilation and hypoxemia: congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), obesity hypoventilation syndrome (OHS), cystic fibrosis (CF) and neuromuscular disorders.

Nocturnal noninvasive positive pressure ventilation in stable COPD: a systematic review and individual patient data meta-analysis

INTRODUCTION

The effects of nocturnal noninvasive positive pressure ventilation (NIPPV) in patients with stable chronic obstructive pulmonary disease (COPD) remain controversial.

METHODS

The Cochrane Airways group Register of Trials, MEDLINE, EMBASE and CINAHL were searched up to August 2012. Individual patient data from randomised controlled trials on NIPPV outcomes were selected for two separate meta-analyses: the first with follow-up of 3 months and the second with 12 months of follow-up. Additionally, subgroup analyses within the NIPPV group comparing IPAP levels, compliance and levels of hypercapnia on change in PaCO2 after 3 months were performed.

RESULTS

Seven trials (245 patients) were included. All studies were considered of moderate to high quality. No significant difference was found between NIPPV and control groups after 3 or 12 months of follow-up when looking at PaCO2 and PaO2, 6-minute walking distance, health-related quality-of-life, forced expiratory volume in 1 s, forced vital capacity, maximal inspiratory pressure and sleep efficiency. Significant differences in change in PaCO2 after 3 months were found for patients ventilated with IPAP levels of at least 18 cm H2O, for patients who used NIPPV for at least 5 h per night as well as for patients with baseline PaCO2 of at least 55 mm Hg when compared to patients with lower IPAP levels, poorer compliance or lower levels of hypercapnia.

DISCUSSION

At present, there is insufficient evidence to support the application of routine NIPPV in patients with stable COPD. However, higher IPAP levels, better compliance and higher baseline PaCO2 seem to improve PaCO2.

Nocturnal non-invasive positive pressure ventilation for stable chronic obstructive pulmonary disease

BACKGROUND

Non-invasive positive pressure ventilation (NIPPV) is effective in treating acute exacerbations of chronic obstructive pulmonary disease (COPD). Nocturnal non-invasive positive pressure ventilation (nocturnal-NIPPV) has been proposed as an intervention for stable hypercapnic patients with COPD.

OBJECTIVES

To assess the effects of nocturnal-NIPPV at home via nasal mask or face mask in people with COPD by using a meta-analysis based on individual patient data (IPD).

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register. We performed the latest search in August 2012.

SELECTION CRITERIA

Randomised controlled trials in people with stable COPD that compared nocturnal-NIPPV at home for at least five hours per night, for at least three consecutive weeks plus standard therapy with standard therapy alone.

DATA COLLECTION AND ANALYSIS

IPD were collected and two review authors assessed risk of bias independently.

MAIN RESULTS

This update of the systematic review on nocturnal-NIPPV in COPD (Wijkstra 2002), has led to the inclusion of three new studies, leading to seven included studies on 245 people. We obtained IPD for all participants in all included studies. The 95% confidence interval (CI) of all outcomes included zero. These included partial pressure of CO2 and O2 in arterial blood, six-minute walking distance (6MWD), health-related quality of life (HRQoL), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), maximal inspiratory pressure (PImax) and sleep efficiency. The mean effect on 6MWD was small at 27.7 m and not statistically significant. Given the width of the 95% CI (-28.1 to 66.3 m), the real effect of NIPPV on 6MWD is uncertain and we cannot exclude an effect that is clinically significant (considering that the minimal clinically difference on 6MWD is around 26 m).

AUTHORS' CONCLUSIONS

Nocturnal-NIPPV at home for at least three months in hypercapnic patients with stable COPD had no consistent clinically or statistically significant effect on gas exchange, exercise tolerance, HRQoL, lung function, respiratory muscle strength or sleep efficiency. Meta-analysis of the two new long-term studies did not show significant improvements in blood gases, HRQoL or lung function after 12 months of NIPPV. However, the small sample sizes of these studies preclude a definite conclusion regarding the effects of NIPPV in COPD.

Home mechanical ventilation: a Canadian Thoracic Society clinical practice guideline

Increasing numbers of patients are surviving episodes of prolonged mechanical ventilation or benefitting from the recent availability of userfriendly noninvasive ventilators. Although many publications pertaining to specific aspects of home mechanical ventilation (HMV) exist, very few comprehensive guidelines that bring together all of the current literature on patients at risk for or using mechanical ventilatory support are available. The Canadian Thoracic Society HMV Guideline Committee has reviewed the available English literature on topics related to HMV in adults, and completed a detailed guideline that will help standardize and improve the assessment and management of individuals requiring noninvasive or invasive HMV. The guideline provides a disease-specific review of illnesses including amyotrophic lateral sclerosis, spinal cord injury, muscular dystrophies, myotonic dystrophy, kyphoscoliosis, post-polio syndrome, central hypoventilation syndrome, obesity hypoventilation syndrome, and chronic obstructive pulmonary disease as well as important common themes such as airway clearance and the process of transition to home. The guidelines have been extensively reviewed by international experts, allied health professionals and target audiences. They will be updated on a regular basis to incorporate any new information.

A randomised crossover trial comparing volume assured and pressure preset noninvasive ventilation in stable hypercapnic COPD

Recent randomised controlled trials suggest non-invasive ventilation may offer benefit in the long-term management of ventilatory failure in stable COPD. The best mode of ventilation is unknown and newer volume assured modes may offer advantages by optimising ventilation overnight when treatment is delivered. This study compares volume assured with pressure preset non-invasive ventilation. Randomised crossover trial including twenty five subjects previously established on long-term non-invasive ventilation to manage COPD with chronic ventilatory failure. Two 8-week treatment periods of volume assured and pressure preset non-invasive ventilation. The primary outcomes were daytime arterial blood gas tensions and mean nocturnal oxygen saturation. Secondary outcomes included lung function, exercise capacity, mean nocturnal transcutaneous carbon dioxide, health status and compliance. No significant differences were seen in primary or secondary outcomes following 8 weeks of treatment when comparing volume assured and pressure preset ventilation. Primary outcomes assessed: mean (standard deviation) PaO(2) 7.8 (1.2) vs 8.1(1) kPa, PaCO(2) 6.7 (1.1) vs 6.3 (1.2) kPa and mean nocturnal oxygenation 90 (4) vs 91 (3)% volume assured versus pressure preset, respectively. Volume assured and pressure preset non-invasive ventilation appear equally effective in the long-term management of ventilatory failure associated with stable COPD.