Effectiveness of treatment with nebulized colistin in patients with COPD

Tolerance and effectiveness of inhaled antibiotics at standard or low doses in COPD patients with chronic Pseudomonas aeruginosa bronchial infection

To evaluate the tolerance and effectiveness of standard doses (StD) and low doses (LoD) of inhaled antibiotics (IA), in patients with chronic obstructive pulmonary disease (COPD) and chronic bronchial infection (CBI) by Pseudomonas aeruginosa (PA). Single-center, observational, retrospective, follow-up study of patients with COPD and CBI by PA treated with IA between 2012 and 2021. One year before and one after the first IA dose were analysed. 87 patients were included (86 men) with a mean FEV1(%) of 46.3%. Intolerance to IA was observed in 54 (62.1%), with a median time of 30 days (IQR: 15, 90). Only a higher FEV1(%) was associated with lower probability of intolerance (hazard ratio: 0.98, 95% confidence interval 0.97 to 0.99; p = 0.021). Seven of 15 (46.6%) patients who did not tolerate StD tolerated LoD. Those unable to tolerate LoD also had worse FEV1(%) (38.4% (SD:18.7%) versus 48.1% (SD: 16.4%); p = 0.018). Treatments lasting 6-12 months improved symptoms and reduced PA isolations (- 2.1; P < 0.001) and exacerbations (-1.7, P < 0.001). In 19 patients LoD treatment reduced exacerbations (-2.1, P = 0.003), days of hospitalization (-7.4, P = 0.036) and PA isolations (-2, P = 0.001) with clinical improvement. Antimicrobial resistance was not observed in any case receiving LoD of IA. More than half of our COPD patients treated with IA for CBI by PA presented respiratory intolerance during the first three months related to greater severity of airway obstruction. Treatment with LoD of IA appears to be an effective and safe alternative for some patients unable to tolerate StD.

Nebulized inhalation drug delivery: clinical applications and advancements in research

Nebulized inhalation administration refers to the dispersion of drugs into small droplets suspended in the gas through a nebulized device, which are deposited in the respiratory tract by inhalation, to achieve the local therapeutic effect of the respiratory tract. Compared with other drug delivery methods, nebulized inhalation has the advantages of fast effect, high local drug concentration, less dosage, convenient application and less systemic adverse reactions, and has become one of the main drug delivery methods for the treatment of respiratory diseases. In this review, we first discuss the characteristics of nebulized inhalation, including its principles and influencing factors. Next, we compare the advantages and disadvantages of different types of nebulizers. Finally, we explore the clinical applications and recent research developments of nebulized inhalation therapy. By delving into these aspects, we aim to gain a deeper understanding of its pivotal role in contemporary medical treatment.

Characterization of Pseudomonas aeruginosa from subjects with diffuse panbronchiolitis

Diffuse panbronchiolitis (DPB) is a rare, idiopathic inflammatory disease primarily diagnosed in East Asian populations. DPB is characterized by diffuse pulmonary lesions, inflammation of the respiratory bronchioles, and bacterial infections of the airway. Historically, sputum cultures reveal Pseudomonas aeruginosa in 22% of DPB patients, increasing to 60% after 4 years from disease onset. Although DPB patients have a known susceptibility to respiratory P. aeruginosa infections, as is observed in other chronic lung diseases such as cystic fibrosis (CF), the characterization of DPB P. aeruginosa strains is limited. In this study, we characterized 24 strains obtained from a cohort of DPB patients for traits previously associated with virulence, including growth, motility, antibiotic susceptibility, lipopolysaccharide structure, and genomic diversity. Our cohort of DPB P. aeruginosa strains exhibits considerable genomic variability when compared with isolates from people with cystic fibrosis chronically colonized with P. aeruginosa and acute P. aeruginosa infection isolates. Similar to CF, DPB P. aeruginosa strains produce a diverse array of modified lipid A structures. Antibiotic susceptibility testing revealed increased resistance to erythromycin, a representative agent of the macrolide antibiotics used to manage DPB patients. Differences in the O-antigen type among P. aeruginosa strains collected from these different backgrounds were also observed. Ultimately, the characterization of DPB P. aeruginosa strains highlights several unique qualities of P. aeruginosa strains collected from chronically diseased airways, underscoring the challenges in treating DPB, CF, and other obstructive respiratory disease patients with P. aeruginosa infections.

IMPORTANCE

Diffuse panbronchiolitis (DPB), a chronic lung disease characterized by persistent P. aeruginosa infection, serves as an informative comparator to more common chronic lung diseases, such as cystic fibrosis (CF). This study aimed to better address the interplay between P. aeruginosa and chronically compromised airway environments through the examination of DPB P. aeruginosa strains, as existing literature regarding DPB is limited to case reports, case series, and clinical treatment guidelines. The evaluation of these features in the context of DPB, in tandem with prevailing knowledge of P. aeruginosa strains collected from more common chronic lung diseases (e.g., CF), can aid in the development of more effective strategies to combat respiratory P. aeruginosa infections in patients with chronic lung diseases.

Synergistic effects of COVID-19 and Pseudomonas aeruginosa in chronic obstructive pulmonary disease: a polymicrobial perspective

This article discusses the connection between the novel coronavirus disease 2019 (COVID-19) caused by the coronavirus-2 (SARS-CoV-2) and chronic obstructive pulmonary disease (COPD). COPD is a multifaceted respiratory illness that is typically observed in individuals with chronic exposure to chemical irritants or severe lung damage caused by various pathogens, including SARS-CoV-2 and Pseudomonas aeruginosa. The pathogenesis of COPD is complex, involving a variety of genotypes and phenotypic characteristics that result in severe co-infections and a poor prognosis if not properly managed. We focus on the role of SARS-CoV-2 infection in severe COPD exacerbations in connection to P.  aeruginosa infection, covering pathogenesis, diagnosis, and therapy. This review also includes a thorough structural overview of COPD and recent developments in understanding its complicated and chronic nature. While COVID-19 is clearly linked to emphysema and chronic bronchitis at different stages of the disease, our understanding of the precise interaction between microbial infections during COPD, particularly with SARS-CoV-2 in the lungs, remains inadequate. Therefore, it is crucial to understand the host-pathogen relationship from the clinician's perspective in order to effectively manage COPD. This article aims to provide a comprehensive overview of the subject matter to assist clinicians in their efforts to improve the treatment and management of COPD, especially in light of the COVID-19 pandemic.

Retrospective Observational Study to Assess Safety and Tolerability of Nebulized Colistin for the Treatment of Patients With Pneumonia in Real-World Settings in Respiratory ICU

INTRODUCTION

Colistin is used to treat hospital-acquired pneumonia and ventilator-associated pneumonia. However, direct drug deposition at the site of infection may improve its efficacy and reduce systemic exposure. The aim of this study was to assess the safety and tolerability of nebulized colistin among Indian patients diagnosed with pneumonia caused by multidrug-resistant gram-negative bacilli in real-world settings.

METHODOLOGY

We retrospectively reviewed the medical records of patients treated with nebulized colistin for pneumonia. We assessed the adverse events and relevant abnormal laboratory findings of nebulized colistin therapy.

RESULTS

All enrolled patients (N=30, males: 22, females: 8; average age: 71.06 years) were treated for 13.36 days. Almost 80% of patients had a history of shortness of breath, which was a major symptom when they were admitted to the hospital. The patients were administered nebulized colistin for an average of six days (8 hours per day). The most common dosing schedule was 1 million international units (MIU)/8 hours. No serious adverse event was observed, and only one patient died while on the treatment but the death was not related to colistin treatment. The average sequential organ failure assessment score for all patients was 6.5.

CONCLUSION

Our study demonstrated the efficient clinical utility and well-tolerated safety profile of nebulized colistin in the treatment of patients with pneumonia. Neurotoxicity and nephrotoxicity were not reported. Since a significant percentage of patients were with chronic respiratory diseases, our study further indicates the safety and effectiveness of nebulized colistin in chronic obstructive pulmonary disease (COPD) patients too.

Prevention of exacerbation in patients with moderate-to-very severe COPD with the intent to modulate respiratory microbiome: a pilot prospective, multi-center, randomized controlled trial

Introduction

Considering the role of bacteria in the onset of acute exacerbation of COPD (AECOPD), we hypothesized that the use of influenza-Streptococcus pneumoniae vaccination, oral probiotics or inhaled amikacin could prevent AECOPD.

Methods

In this pilot prospective, muti-central, randomized trial, moderate-to-very severe COPD subjects with a history of moderate-to-severe exacerbations in the previous year were enrolled and assigned in a ratio of 1:1:1:1 into 4 groups. All participants were managed based on the conventional treatment recommended by GOLD 2019 report for 3 months, with three groups receiving additional treatment of inhaled amikacin (0.4 g twice daily, 5-7 days monthly for 3 months), oral probiotic Lactobacillus rhamnosus GG (1 tablet daily for 3 months), or influenza-S. pneumoniae vaccination. The primary endpoint was time to the next onset of moderate-to-severe AECOPD from enrollment. Secondary endpoints included CAT score, mMRC score, adverse events, and survival in 12 months.

Results

Among all 112 analyzed subjects (101 males, 96 smokers or ex-smokers, mean ± SD age 67.19 ± 7.39 years, FEV1 41.06 ± 16.09% predicted), those who were given dual vaccination (239.7 vs. 198.2 days, p = 0.044, 95%CI [0.85, 82.13]) and oral probiotics (248.8 vs. 198.2 days, p = 0.017, 95%CI [7.49, 93.59]) had significantly delayed onset of next moderate-to-severe AECOPD than those received conventional treatment only. For subjects with high symptom burden, the exacerbations were significantly delayed in inhaled amikacin group as compared to the conventional treatment group (237.3 vs. 179.1 days, p = 0.009, 95%CI [12.40,104.04]). The three interventions seemed to be safe and well tolerated for patient with stable COPD.

Conclusion

The influenza-S. pneumoniae vaccine and long-term oral probiotic LGG can significantly delay the next moderate-to-severe AECOPD. Periodically amikacin inhalation seems to work in symptomatic patients. The findings in the current study warrants validation in future studies with microbiome investigation.Clinical trial registration:https://clinicaltrials.gov/, identifier NCT03449459.

Inhaled Colistimethate Sodium in the Management of Patients with Bronchiectasis Infected by Pseudomonas aeruginosa: A Narrative Review of Current Evidence

International guidelines on the treatment of bronchiectasis indicate that the use of inhaled antibiotics is effective, especially in symptomatic chronic bronchial infection (CBI) due to Pseudomonas aeruginosa (PA). To date, however, no such treatment has been approved by regulatory agencies. Of the inhaled antibiotics on the market, colistimethate sodium (colistin) is one of the most used in many countries, either in its nebulized presentation or as dry powder. Among the characteristics of this antibiotic, it is worth noting that its main target is the lipopolysaccharide in the outer membrane of the cell wall of gram-negative bacteria and that it has a low rate of resistance to PA (<1%). Most observational studies have shown that the use of colistin in patients with bronchiectasis and CBI due to PA results in a decrease in both the number and severity of exacerbations, an improvement in quality of life, a decrease in sputum volume and purulence, and a high rate of PA eradication, although there are no clear differences with respect to other inhaled antibiotics. However, the lack of randomized clinical trials (RCT) with positive results for its main variable (exacerbations) in an intention-to-treat analysis has prevented its approval by regulatory agencies as a formal indication for use in bronchiectasis. The PROMIS program, made up of two RCT with identical methodology, is currently underway. The first of these RCT (already concluded) has demonstrated a clearly positive effect on the group randomized to colistin in its main variable (number of annual exacerbations), while the results of the second are still pending. This review presents exhaustive information on the pharmacological and microbiological characteristics of colistin, the results of the studies carried out to date, and the future challenges associated with this treatment.

Antimicrobial therapies for prevention of recurrent acute exacerbations of COPD (AECOPD): beyond the guidelines

BACKGROUND

Unfortunately, many COPD patients continue to exacerbate despite good adherence to GOLD Class D recommended therapy. Acute exacerbations lead to an increase in symptoms, decline in lung function and increased mortality rate. The purpose of this review is to do a literature search for any prophylactic anti-microbial treatment trials in GOLD class D patients who 'failed' recommended therapy and discuss the role of COPD phenotypes, lung and gut microbiota and co-morbidities in developing a tailored approach to anti-microbial therapies for high frequency exacerbators.

MAIN TEXT

There is a paucity of large, well-conducted studies in the published literature to date. Factors such as single-centre, study design, lack of well-defined controls, insufficient patient numbers enrolled and short follow-up periods were significant limiting factors in numerous studies. One placebo-controlled study involving more than 1000 patients, who had 2 or more moderate exacerbations in the previous year, demonstrated a non-significant reduction in exacerbations of 19% with 5 day course of moxifloxacillin repeated at 8 week intervals. In Pseudomonas aeruginosa (Pa) colonised COPD patients, inhaled antimicrobial therapy using tobramycin, colistin and gentamicin resulted in significant reductions in exacerbation frequency. Viruses were found to frequently cause acute exacerbations in COPD (AECOPD), either as the primary infecting agent or as a co-factor. However, other, than the influenza vaccination, there were no trials of anti-viral therapies that resulted in a positive effect on reducing AECOPD. Identifying clinical phenotypes and co-existing conditions that impact on exacerbation frequency and severity is essential to provide individualised treatment with targeted therapies. The role of the lung and gut microbiome is increasingly recognised and identification of pathogenic bacteria will likely play an important role in personalised antimicrobial therapies.

CONCLUSION

Antimicrobial therapeutic options in patients who continue to exacerbate despite adherence to guidelines-directed therapy are limited. Phenotyping patients, identification of co-existing conditions and assessment of the microbiome is key to individualising antimicrobial therapy. Given the impact of viruses on AECOPD, anti-viral therapeutic agents and targeted anti-viral vaccinations should be the focus of future research studies.

Effectiveness and Safety of Inhaled Antibiotics in Patients With Chronic Obstructive Pulmonary Disease. A Multicentre Observational Study

BACKGROUND

We aimed to describe the effectiveness and safety of inhaled antibiotics in chronic obstructive pulmonary disease (COPD) patients, as well as the patient profile in which they are usually prescribed and the patient groups that can most benefit from this treatment.

METHODS

Multicentre retrospective observational cohort study in COPD patients who had received ≥1 dose of inhaled antibiotics in the last 5 years. Clinical data from the two years prior to and subsequent to the start of the treatment were compared.

PRIMARY OUTCOME

COPD exacerbations.

SECONDARY OUTCOMES

side effects, symptomatology (sputum purulence, dyspnoea), microbiological profile and pathogen eradication.

RESULTS

Of 693 COPD patients analyzed (aged 74.1; 86.3% men; mean FEV₁=43.7%), 71.7% had bronchiectasis and 46.6% presented chronic bronchial infection (CBI) by Pseudomonas aeruginosa (PA). After 1 year of treatment with inhaled antibiotics, there was a significant decrease in the number of exacerbations (-33.3%; P<.001), hospital admissions (-33.3%; P<.001) and hospitalization days (-26.2%; P=.003). We found no difference in effectiveness between patients with or without associated bronchiectasis. Positive patient outcomes were more pronounced in PA-eradicated patients. We found a significant reduction in daily expectoration (-33.1%; P=.024), mucopurulent/purulent sputum (-53.9%; P<.001), isolation of any potentially pathogenic microorganisms (PPM) (-16.7%; P<.001), CBI by any PPM (-37.4%; P<.001) and CBI by PA (-49.8%; P<.001). CBI by any PPM and ≥three previous exacerbations were associated with a better treatment response. 25.4% of patients presented non-severe side-effects, the most frequent of these being bronchospasm (10.5%), dyspnoea (8.8%) and cough (1.7%).

CONCLUSIONS

In COPD patients with multiple exacerbations and/or CBI by any PPM (especially PA), inhaled antibiotics appear to be an effective and safe treatment, regardless of the presence of bronchiectasis.

Therapeutic peptides for the treatment of cystic fibrosis: Challenges and perspectives

Cystic fibrosis (CF) is the most common amongst rare genetic diseases, affecting more than 70.000 people worldwide. CF is characterized by a dysfunctional chloride channel, termed cystic fibrosis conductance regulator (CFTR), which leads to the production of a thick and viscous mucus layer that clogs the lungs of CF patients and traps pathogens, leading to chronic infections and inflammation and, ultimately, lung damage. In recent years, the use of peptides for the treatment of respiratory diseases, including CF, has gained growing interest. Therapeutic peptides for CF include antimicrobial peptides, inhibitors of proteases, and modulators of ion channels, among others. Peptides display unique features that make them appealing candidates for clinical translation, like specificity of action, high efficacy, and low toxicity. Nevertheless, the intrinsic properties of peptides, together with the need of delivering these compounds locally, e.g. by inhalation, raise a number of concerns in the development of peptide therapeutics for CF lung disease. In this review, we discuss the challenges related to the use of peptides for the treatment of CF lung disease through inhalation, which include retention within mucus, proteolysis, immunogenicity and aggregation. Strategies for overcoming major shortcomings of peptide therapeutics will be presented, together with recent developments in peptide design and optimization, including computational analysis and high-throughput screening.

Consensus Document on the Diagnosis and Treatment of Chronic Bronchial Infection in Chronic Obstructive Pulmonary Disease

Although the chronic presence of microorganisms in the airways of patients with stable chronic obstructive pulmonary disease (COPD) confers a poor outcome, no recommendations have been established in disease management guidelines on how to diagnose and treat these cases. In order to guide professionals, the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) has prepared a document which aims to answer questions on the clinical management of COPD patients in whom microorganisms are occasionally or habitually isolated. Since the available scientific evidence is too heterogeneous to use in the creation of a clinical practice guideline, we have drawn up a document based on existing scientific literature and clinical experience, addressing the definition of different clinical situations and their diagnosis and management. The text was drawn up by consensus and approved by a large group of respiratory medicine experts with extensive clinical and scientific experience in the field, and has been endorsed by the SEPAR Scientific Committee.

Inhaled therapies for chronic obstructive pulmonary disease: a systematic review and meta-analysis

OBJECTIVES

To integrate evidence from randomised controlled trials (RCTs) and observational studies on the efficacy of inhaled treatments for chronic obstructive pulmonary disease using network meta-analyses.

METHODS

Systematic searches MEDLINE and Embase based on predetermined criteria. Network meta-analyses of RCTs investigated efficacy on exacerbations (long-term: ≥20 weeks of treatment; short-term: <20 weeks), lung function (≥12 weeks), health-related quality of life, mortality and adverse events. Qualitative comparisons of efficacies between RCTs and observational studies.

RESULTS

212 RCTs and 19 observational studies were included. Compared with combined long-acting beta-adrenoceptor agonists and long-acting muscarinic antagonists (LABA+LAMA), triple therapy (LABA+LAMA+inhaled corticosteroid) was significantly more effective at reducing exacerbations (long-term 0.85 (95% CI: 0.78 to 0.94; short-term 0.67 (95% CI: 0.49 to 0.92)) and mortality (0.72 (95% CI: 0.59 to 0.89)) but was also associated with increased pneumonia (1.35 (95% CI: 1.10 to 1.67)). No differences in lung function (0.02 (95% CI: -0.10 to 0.14)), health-related quality of life (-1.12 (95% CI: -3.83 to 1.59)) or other adverse events (1.02 (95% CI: 0.96 to 1.08)) were found. Most of the observational evidence trended in the same direction as pooled RCT data.

CONCLUSION

Further evidence, especially pragmatic trials, are needed to fully understand the characteristics of patient subgroups who may benefit from triple therapy and for those whom the extra risk of adverse events, such as pneumonia, may outweigh any benefits.

PROSPERO REGISTRATION NUMBER

CRD42018088013.

Nebulized Therapies in COPD: Past, Present, and the Future

Current guidelines recommend inhalation therapy as the preferred route of drug administration for treating patients with chronic obstructive pulmonary disease (COPD). Inhalation devices consist of nebulizers and handheld inhalers, such as dry-powder inhalers (DPIs), pressurized metered-dose inhalers (pMDIs), and soft mist inhalers (SMIs). Although pMDIs, DPIs and SMIs may be appropriate for most patients with COPD, certain patient populations may have challenges with these devices. Patients who have cognitive, neuromuscular, or ventilatory impairments (and receive limited assistance from caregivers), as well as those with suboptimal peak inspiratory flow may not derive the full benefit from handheld inhalers. A considerable number of patients are not capable of producing a peak inspiratory flow rate to overcome the internal resistance of DPIs. Furthermore, patients may have difficulty coordinating inhalation with device actuation, which is required for pMDIs and SMIs. However, inhalation devices such as spacers and valved holding chambers can be used with pMDIs to increase the efficiency of aerosol delivery. Nebulized treatment provides patients with COPD an alternative administration route that avoids the need for inspiratory flow, manual dexterity, or complex hand-breath coordination. The recent approval of two nebulized long-acting muscarinic antagonists has added to the extensive range of nebulized therapies in COPD. Furthermore, with the availability of quieter and more portable nebulizer devices, nebulization may be a useful treatment option in the management of certain patient populations with COPD. The aim of this narrative review was to highlight recent updates and the treatment landscape in nebulized therapy and COPD. We first discuss the pathophysiology of patients with COPD and inhalation device considerations. Second, we review the updates on recently approved and newly marketed nebulized treatments, nebulized treatments currently in development, and technological advances in nebulizer devices. Finally, we discuss the current applications of nebulized therapy in patients with COPD.

Current Challenges in Chronic Bronchial Infection in Patients with Chronic Obstructive Pulmonary Disease

Currently, chronic obstructive pulmonary disease (COPD) patients and their physicians face a number of significant clinical challenges, one of which is the high degree of uncertainty related to chronic bronchial infection (CBI). By reviewing the current literature, several challenges can be identified, which should be considered as goals for research. One of these is to establish the bases for identifying the biological and clinical implications of the presence of potentially pathogenic microorganisms in the airways that should be more clearly elucidated according to the COPD phenotype. Another urgent area of research is the role of long-term preventive antibiotics. Clinical trials need to be carried out with inhaled antibiotic therapy to help clarify the profile of those antibiotics. The role of inhaled corticosteroids in patients with COPD and CBI needs to be studied to instruct the clinical management of these patients. Finally, it should be explored and confirmed whether a suitable antimicrobial treatment during exacerbations may contribute to breaking the vicious circle of CBI in COPD. The present review addresses the current state of the art in these areas to provide evidence which will enable us to progressively plan better healthcare for these patients.

Clinical Management of Respiratory Adverse Events Associated With Amikacin Liposome Inhalation Suspension: Results From a Patient Survey

Patients with Mycobacterium avium complex lung disease treated with amikacin liposome inhalation suspension (ALIS) at 2 clinics in the United States were surveyed to assess the frequency and management of ALIS-associated respiratory adverse events. Most respondents experienced these events, but management through physician-guided measures (eg, bronchodilator use, oral rinses, and/or temporary dosing adjustments) resulted in symptomatic improvement.

Nebulized Colistin And Continuous Cyclic Azithromycin In Severe COPD Patients With Chronic Bronchial Infection Due To Pseudomonas aeruginosa: A Retrospective Cohort Study

Introduction

Long-term use of nebulized or oral antibiotics is common in the treatment of cystic fibrosis and non-cystic fibrosis bronchiectasis. To date, however, few studies have focused on the use of nebulized antibiotics in COPD patients. The aims of this study are: to establish whether a combination of nebulized colistin plus continuous cyclic azithromycin in severe COPD patients with chronic bronchial infection due to Pseudomonas aeruginosa reduces the frequency of exacerbations, and to assess the effect of this treatment on microbiological sputum isolates.

Material and methods

A retrospective cohort was created for the analysis of patients with severe COPD and chronic bronchial infection due to P. aeruginosa treated with nebulized colistin at the Respiratory Day Care Unit between 2005 and 2015. The number and characteristics of COPD exacerbations (ECOPD) before and up to two years after the introduction of nebulized colistin treatment were recorded.

Results

We analyzed 32 severe COPD patients who received nebulized colistin for at least three months (median 17 months [IQR 7-24]). All patients but one received combination therapy with continuous cyclic azithromycin (median 24 months [IQR 11-30]). A significant reduction in the number of ECOPD from baseline of 38.3% at two years of follow-up was observed, with a clear decrease in P. aeruginosa ECOPD (from 59.5% to 24.6%) and a P. aeruginosa eradication rate of 28% over the two-year follow-up.

Conclusion

In patients with severe COPD and chronic bronchial infection due to P. aeruginosa, combination therapy with nebulized colistin and continuous cyclic azithromycin significantly reduced the number of ECOPD, with a marked decrease in P. aeruginosa sputum isolates.

Protocol for a systematic literature review and network meta-analysis of the clinical benefit of inhaled maintenance therapies in chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) exacerbations progress the course of disease and impair lung function. Inhaled maintenance therapy reduces exacerbations. It is not yet established which inhaled therapy combination is best to reduce exacerbations, lung function decline and symptom burden.

METHODS AND ANALYSIS

MEDLINE, EMBASE and the Cochrane Library will be searched for articles between January 2011 and May 2018 using a pre-specified search strategy. Conference proceedings will be searched. Systematic reviews (with or without meta-analysis), randomised controlled trials (RCTs), cohort studies and case controlled studies comparing six interventions comprising different combinations of long-acting bronchodilators and inhaled corticosteroids in unison or on their own. The primary outcome is the reduction in moderate-to-severe exacerbations. Secondary outcomes include: lung function, quality of life, mortality and other adverse events. Titles and abstracts will screened by the primary researcher. A second reviewer will repeat this on a proportion of records. The Population, Intervention, Comparator, Outcomes and Study framework will be used for data extraction. A network meta-analyses of outcomes from RCTs and real-world evidence will be integrated if feasible. The 95% credible interval will be used to assess the statistical significance of each summary effect. Ranking of interventions will be based on their surface under cumulative ranking area.

ETHICS AND DISSEMINATION

COPD exacerbations are burdensome to patients. We aim to report results that provide clinicians with a more informed choice of which inhaled therapy combinations are best to reduce exacerbations, improve disease burden and reduce lung function and exercise capacity decline, compared with the potential harms, in certain populations with COPD.

PROSPERO REGISTRATION NUMBER

CRD42018088013.

Microbiological Progress in Patients with Bronchial Infection with <b><i>Pseudomonas aeruginosa</i></b> Treated with Nebulised Colistin

<b><i>Background:</i></b> Inhaled antibiotics allow the delivery of higher drug concentrations at the site of infection without the systemic adverse effects observed with the use of parenteral or oral antibiotics. These antibiotics have shown to decrease the number of exacerbations, reduce bacterial load or improve pulmonary function in several chronic respiratory conditions. <b><i>Objectives:</i></b> The aim of this study was to describe changes in the bacteriology of sputum in patients with chronic bronchial infection with <i>Pseudomonas aeruginosa</i> treated with nebulised colistin. <b><i>Material and Methods:</i></b> All patients with chronical infection with <i>P. aeruginosa</i> treated with nebulised colistin attending a day care unit during a 5-year (January 2010 to December 2014) period were included. Repeated-measures <i>t</i> tests were used to assess whether the introduction of colistin was associated with changes in the number of exacerbations or the length of the hospitalisations. <b><i>Results:</i></b> Treatment with colistin was associated with a decrease in the number of ambulatory exacerbations (1.87–1.1, <i>p</i> = 0.007), of hospital exacerbations (1.3–0.7, <i>p</i> = 0.010) and of length of stay (15.7–8.6 days, <i>p</i> = 0.005). There was no linear trend in the proportion of isolate Enterobacteriaceae, gram-positive cocci, <i>Haemophilus influenzae</i> or fungi. Isolation of Enterobacteriaceae within 1 year after the beginning of the treatment with nebulised colistin was associated with an increase in the number of ambulatory exacerbations (incidence rate ratio 1.99, 95% CI 1.05–3.79). <b><i>Conclusions:</i></b> Nebulised colistin was effective in the treatment of chronic infection with <i>P. aeruginosa,</i> and no significant changes in the microbiological evolution were observed. Isolation of Enterobacteriaceae within 1 year after the beginning of the treatment with nebulised colistin was associated with an increase in the number of exacerbations.

[Integral approach to the acute exacerbation of chronic obstructive pulmonary disease]

Chronic obstructive pulmonary disease is a set of clinical processes that have in common a chronic and progressive obstruction to airflow, with episodes of exacerbation. These exacerbations are more frequent and severe over time, deteriorating the lung function. The main cause of exacerbations is bacterial infection. There are multiple guidelines and documents that statement the management of this pathology. However, they focus primarily on the treatment during the stable phase. This document addresses the problem of acute exacerbation due to an infection from a multidisciplinary perspective, focusing on the integral approach to the process, and including etiology, microbiological studies, resistance to antimicrobials, risk stratification and initial empirical therapeutic management (antibiotic and concomitant). In addition, it includes an approach to more complex aspects such as the management of special populations (elderly and immunosuppressed) or therapeutic failure. Finally, more controversial topics such as prophylaxis of infection or palliative treatment are specifically discussed.

Inhalation Techniques Used in Patients with Respiratory Failure Treated with Noninvasive Mechanical Ventilation

The administration of aerosolized medication is a basic therapy for patients with numerous respiratory tract diseases, including obstructive airway diseases (OADs), cystic fibrosis (CF), and infectious airway diseases. The management and care for patients requiring mechanical ventilation remains one of the greatest challenges for medical practitioners, both in intensive care units (ICUs) and pulmonology wards. Aerosol therapy is often necessary for patients receiving noninvasive ventilation (NIV), which may be stopped for the time of drug delivery and administered through a metered-dose inhaler or nebulizer in the traditional way. However, in most severe cases, this may result in rapid deterioration of the patient's clinical condition. Unfortunately, only limited number of original well-planned studies addressed this problem. Due to inconsistent information coming from small studies, there is a need for more precise data coming from large prospective real life studies on inhalation techniques in patients receiving NIV.