Predictors of pneumothorax following endoscopic valve therapy in patients with severe emphysema

First real-time imaging of bronchoscopic lung volume reduction by electrical impedance tomography

BACKGROUND

Bronchoscopic lung volume reduction (BLVR) with one-way endobronchial valves (EBV) has better outcomes when the target lobe has poor collateral ventilation, resulting in complete lobe atelectasis. High-inspired oxygen fraction (FIO2) promotes atelectasis through faster gas absorption after airway occlusion, but its application during BLVR with EBV has been poorly understood. We aimed to investigate the real-time effects of FIO2 on regional lung volumes and regional ventilation/perfusion by electrical impedance tomography (EIT) during BLVR with EBV.

METHODS

Six piglets were submitted to left lower lobe occlusion by a balloon-catheter and EBV valves with FIO2 0.5 and 1.0. Regional end-expiratory lung impedances (EELI) and regional ventilation/perfusion were monitored. Local pocket pressure measurements were obtained (balloon occlusion method). One animal underwent simultaneous acquisitions of computed tomography (CT) and EIT. Regions-of-interest (ROIs) were right and left hemithoraces.

RESULTS

Following balloon occlusion, a steep decrease in left ROI-EELI with FIO2 1.0 occurred, 3-fold greater than with 0.5 (p < 0.001). Higher FIO2 also enhanced the final volume reduction (ROI-EELI) achieved by each valve (p < 0.01). CT analysis confirmed the denser atelectasis and greater volume reduction achieved by higher FIO2 (1.0) during balloon occlusion or during valve placement. CT and pocket pressure data agreed well with EIT findings, indicating greater strain redistribution with higher FIO2.

CONCLUSIONS

EIT demonstrated in real-time a faster and more complete volume reduction in the occluded lung regions under high FIO2 (1.0), as compared to 0.5. Immediate changes in the ventilation and perfusion of ipsilateral non-target lung regions were also detected, providing better estimates of the full impact of each valve in place.

TRIAL REGISTRATION

Not applicable.

Bronchoscopic lung volume reduction in emphysema: a review

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) poses a substantial burden on the healthcare system and is currently considered the sixth leading cause of death in the United States. Emphysema, as evidenced by severe air-trapping in patients with COPD, leads to significant dyspnea and morbidity. Lung volume reduction via surgery or minimally invasive endobronchial interventions are currently available, which improve lung function and quality of life.

RECENT FINDINGS

Newer studies have noted a survival benefit in patients post bronchoscopic lung volume reduction vs. those subjected to standard of care. The presence of collateral ventilation is one of the most common impeding factors to placing endobronchial valves, and if placed, these patients might not achieve lobar atelectasis; however, there are newer modalities that are now available for patients with collateral ventilation which we have described.

SUMMARY

Combining standard of care treatment that includes smoking cessation, bronchodilators, preventive care including vaccinations, pulmonary rehabilitation, and endobronchial treatment using various interventions in decreasing hyperinflation improves quality of life and may improve survival and hence significantly reduce the burden of COPD on healthcare.

Surgical and bronchoscopic pulmonary function-improving procedures in lung emphysema

COPD is a highly prevalent, chronic and irreversible obstructive airway disease without curative treatment. Standard therapeutic strategies, both non-pharmacological and pharmacological, have only limited effects on lung function parameters of patients with severe disease. Despite optimal pharmacological treatment, many patients with severe COPD still have a high burden of dyspnoea and a poor quality of life. If these patients have severe lung emphysema, with hyperinflation as the driver of symptoms and exercise intolerance, lung volume reduction may be an effective treatment with a significant impact on lung function, exercise capacity and quality of life. Currently, different lung volume reduction approaches, both surgical and bronchoscopic, have shown encouraging results and have been implemented in COPD treatment recommendations. Nevertheless, choosing the optimal lung volume reduction strategy for an individual patient remains challenging. Moreover, there is still room for improving durability of effect and safety in all available procedures. Ongoing and innovative research is essential to push this field forwards. This review provides an overview of results and limitations of the current lung volume reduction options for patients with severe lung emphysema and hyperinflation.

Long-Term Follow-Up of Intralobar Bullae After Endobronchial Valve Treatment for Emphysema

Endoscopic lung volume reduction using unidirectional endobronchial valves is a new technique in the treatment of patients with severe emphysema. However, the movements of the thoracic structures after endobronchial valves insertion are still unpredictable We report the unusual outcome of six patients after valves insertion in the left upper lobe. They all developed a complete atelectasis of the target lobe, a pneumothorax and sequential genuine bullae in the treated left lung of unknown etiology. The chest CT scan prior to the valves insertion was unremarkable. Three patients developed an air–liquid level in the bullae the day before a bacterial infection of their left lower lobe. The three other patients had an uneventful spontaneous resolution of their bullae at long-term follow-up. Therefore, a conservative attitude should be followed in this particular setting.

Meta-analysis and Systematic Review of Bronchoscopic Lung Volume Reduction Through Endobronchial Valves in Severe Emphysema

BACKGROUND

Pharmacologic therapeutics for advanced emphysema have limited benefit. Bronchoscopic lung volume reduction with endobronchial valves (EBVs) have reported improvements in lung function, breathlessness, and quality of life through randomized clinical trials, with less morbidity as comparted to Surgical Lung volume Reduction. We here present a Meta-analysis and systematic review of bronchoscopic lung volume reduction in advanced chronic obstructive lung disease patients.

METHODS

PubMed (NLM), Embase (Elsevier), and Web of Science (Clarivate Analytics) search was conducted using a combination of keywords and subject headings. The search was confined to the last 15 years and was completed on October 23, 2020. Only placebo-controlled randomized control trials of emphysema patients with EBV were included. Quality assessment was done by 2 independent reviewers.

RESULTS

Nine studies were included for the meta-analysis with a total number of 1383 patients of whom 888 received EBV and 495 standard of care (SOC) medications. Our Metanalysis show statistically significant improvement in forced expiratory volume in first second, percentage forced expiratory volume in first second, St. George's respiratory questionnaire, and 6-minute walk distance in EBV group compared with SOC. Residual volume had statistically significant reduction after EBV placement compared with SOC. These differences continued to be present during short-term (<=6 mo) and long-term follow-up (>=6 mo). These improvements were even higher when the EBV patients'. Collateral ventilation was negative/fissure was intact (CV-/FI >90%). The rate of hemoptysis and pneumothorax was higher in the EBV group compared with SOC, however, did not lead to increased fatal outcomes.

CONCLUSION

In conclusion, EBV has favorable effects on patients' outcomes in patients who have heterogeneous emphysema particularly with no collateral ventilation.

Complications of Endobronchial Valve Placement for Bronchoscopic Lung Volume Reduction: Insights From the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE)

BACKGROUND

Patients with advanced emphysema experience breathlessness due to impaired respiratory mechanics and diaphragm dysfunction. Bronchoscopic lung volume reduction (BLVR) is a minimally invasive bronchoscopic procedure done to reduce hyperinflation and air trapping, promoting atelectasis in the targeted lobe and allowing improved respiratory mechanics. Real-world data on safety and complications outside of clinical trials of BLVR are limited.

METHODS

We queried the US Food and Drug Administrations (FDA) Manufacturers and User Device Experience database from May 2019 to June 2020 for reports involving BLVR with endobronchial valve (EBV) placement. Events were reviewed for data analysis.

RESULTS

We identified 124 cases of complications during BLVR with EBV implantation. The most-reported complication was pneumothorax (110/124, 89%), all of which required chest tube placement. A total of 54 of these cases (54/110, 49%) were complicated by persistent air leak requiring additional interventions. Repeat bronchoscopy was needed to remove the valves in 28 patients, 12 were discharged with a Heimlich valve, and 10 had an additional pleural catheter placed. The other complications of BLVR with EBV placement included respiratory failure (6/124, 5%), pneumonia (4/124, 3%), hemoptysis (2/124, 1.6%), valve migration (1/124, 1%), and pleural effusion (1/124, 1%). A total of 14 deaths were reported during that year.

CONCLUSION

Pneumothorax is the most-reported complication for BLVR with EBV placement, and in 65% of cases, pneumothorax is managed without removing valves. Importantly, 14 deaths were reported during that timeframe. Further studies are needed to estimate the true magnitude of the complications associated with BLVR.

Early Spirometry Following Bronchoscopic Lung Volume Reduction with Endobronchial Valves

Bronchoscopic lung volume reduction (BLVR) by endobronchial valve (EBV) implantation has been shown to improve dyspnea, pulmonary function, exercise capacity, and quality of life in highly selected patients with severe emphysema and hyperinflation. The most frequent adverse event is a pneumothorax (PTX), occurring in approximately one-fifth of the cases due to intrathoracic volume shifts. The majority of these incidents are observed within 48 h post-procedure. However, the delayed occurrence of PTX after hospital discharge is a matter of concern. There is currently no approved concept for its prevention. Particularly, it is unknown whether and when respiratory manoeuvers such as spirometry post EBV treatment are feasible and safe. As per standard operating procedure at the University Hospital Zurich, early spirometry is scheduled after BLVR and prior to the discharge of the patient in order to monitor treatment success. The aim of our retrospective study was to investigate the feasibility and safety of early spirometry. In addition, we hypothesized that early spirometry could be useful to identify patients at risk for late PTX, which may occur after hospital discharge. All patients who underwent BLVR using EBVs between January 2018 and January 2020 at our hospital were enrolled in this study. After excluding 16 patients diagnosed post-procedure with PTX and four patients for other reasons, early spirometry was performed in 61 cases. There was neither a clinically relevant PTX during or after early spirometry nor a late PTX following hospital discharge. In conclusion, we found early spirometry, conducted not sooner than three days following EBV treatment, to be feasible and safe. Furthermore, early spirometry seems to be a useful predictor for successful BLVR, and it may help to decide whether a patient can be discharged. Given the small sample size and the retrospective design of our study, a prospective study that includes routine chest imaging after early spirometry to definitively exclude PTX is needed to recommend early spirometry as part of the standard protocol following EBV treatment.

Endobronchial treatment of severe asthma and severe emphysema with hyperinflation

PURPOSE OF REVIEW

The field of interventional pulmonology has ushered in a wave of innovations for individuals with obstructive airways disease in whom established medical therapies have failed. Leading the charge are bronchial thermoplasty for severe refractory asthma and uni-directional valves for severe emphysema with hyperinflation: both have received regulatory approvals in the United Kingdom and United States. With the commissioning of these novel treatments comes new challenges relating to implementation, positioning within therapeutic algorithms, honing of patient selection, and establishing long-term safety and benefits beyond 5 years.

RECENT FINDINGS

This review summarises the evidence for their safety and efficacy, predictors of therapeutic response, mechanism(s) of action and emerging data supporting the durability of outcomes out to at least ten years.

SUMMARY

It is anticipated the experience of treating increasing numbers of patients, the adoption of international registries, and ongoing research evaluations will serve to optimise these therapies for future generations of patients.

Two-Stage Bronchoscopic Endobronchial Valve Treatment Can Lead to Progressive Lung Volume Reduction and May Decrease Pneumothorax Risk

Background

Since successful development of endobronchial valves (EBV) as treatment for severe emphysema, its main complication, pneumothorax, remains an important concern.

Objective

We hypothesized that a two-step EBV implantation, during two distinct iterative procedures could lead to a more progressive target lobe volume reduction (TLVR) and thus ipsilateral lobe re-expansion, resulting in a significant decrease in the pneumothorax rate.

Methods

This retrospective bi-center study carried out by Limoges and Toulouse University Hospitals included patients following the inclusion criteria established by the BLVR expert panel. All patients were treated by two distinct procedures: first, EBVs were placed in all but the most proximal segment or sub-segment. The remaining segment was treated subsequently. All patients had a complete evaluation before treatment, and 3 months after the second procedure.

Results

Out of 58 patients included, only 4 pneumothoraxes (7%) occurred during the study. The other complications were pneumonia and severe COPD exacerbation (8.6% and 13.7% of patients, respectively). Significant improvement was found for FEV1 (+19.6 ± 25%), RV (-468 ± 960mL), 6MWD (30 ± 85m), BODE Index (-1.4 ± 1.8 point) and TLVR (50.6 ± 35.1%). Significant TLVR (MCID) was obtained in 74.1% of patients (43/58).

Conclusion

This new approach using EBV could reduce the incidence of pneumothorax without increasing other complication rates. Clinical and physiological outcomes are similar to those reported in studies using the conventional single-step treatment.

Expert Statement: Pneumothorax Associated with One-Way Valve Therapy for Emphysema: 2020 Update

For selected patients with advanced emphysema, bronchoscopic lung volume reduction with one-way valves can lead to clinically relevant improvements of airflow obstruction, hyperinflation, exercise capacity, and quality of life. The most common complication of this procedure is pneumothorax with a prevalence of up to ±34% of the treated patients. Patients who develop a pneumothorax also experience meaningful clinical benefits once the pneumothorax is resolved. Timely resolution of a post-valve treatment pneumothorax requires skilled and adequate pneumothorax management. This expert panel statement is an updated recommendation of the 2014 statement developed to help guide pneumothorax management after valve placement. Additionally, mechanisms for pneumothorax development, risk assessment, prevention of pneumothorax, and outcomes after pneumothorax are addressed. This recommendation is based on a combination of the current scientific literature and expert opinion, which was obtained through a modified Delphi method.

Lung Volume Reduction in Pulmonary Emphysema

Severe emphysema with hyperinflation presents a therapeutic challenge. Inhaled medication has limited efficacy in individuals with mechanical constraints to the respiratory pump and impaired gas exchange. Lung volume reduction surgery (LVRS) reestablishes some semblance of normal physiology, resecting grossly expanded severely diseased tissue to restore the function of compromised relatively healthy lung, and has been shown to significantly improve exercise capacity, quality of life, and survival, especially in individuals with upper-lobe predominant emphysema and low-baseline exercise capacity, albeit with higher early morbidity and mortality. Bronchoscopic lung volume reduction achieved by deflating nonfunctioning parts of the lung is promoted as a less invasive and safer approach. Endobronchial valve implantation has demonstrated comparable outcomes to LVRS in selected individuals and has recently received approvals by the National Institute of Clinical Excellence in the United Kingdom and the Food and Drug Administration in the United States of America. Endobronchial coils are proving a viable treatment option in severe hyperinflation in the presence of collateral ventilation in selected cases of homogeneous disease. Modalities including vapor and sealant are delivered using a segmental strategy preserving healthier tissue within the same target lobe-efficacy and safety-data are, however, limited. This article will review the data supporting these novel technologies.

Endobronchial valves for severe emphysema

The results of the randomised controlled trials investigating the bronchoscopic lung volume reduction treatment using endobronchial valves (EBV) are promising, and have led to their inclusion in treatment guidelines, US Food and Drug Administration approval and inclusion in routine care in an increasing number of countries. The one-way valve treatment has advanced and is now a regular treatment option. However, this new phase will lead to new challenges in terms of implementation. We believe that key issues in future research concern advanced patient selection, improved methods for target lobe selection, increased knowledge on the predictive risk of a pneumothorax, positioning of pulmonary rehabilitation in conjunction with the EBV treatment, the positioning of lung volume reduction surgery versus EBV treatment, and the long-term efficacy, adverse events, impact on exacerbations and hospitalisations, costs and survival. Hopefully, the increasing number of patients treated, the setup of (inter)national registries and future research efforts will further optimise all aspects of this treatment.

The REACH Trial: A Randomized Controlled Trial Assessing the Safety and Effectiveness of the Spiration® Valve System in the Treatment of Severe Emphysema

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has become a leading cause of morbidity and mortality in China, with tobacco smoke, air pollution, and occupational biohazards being the major risk factors.

OBJECTIVES

The REACH trial is a multicenter, prospective, randomized controlled trial undertaken in China to assess the safety and effectiveness of the Spiration® Valve System (SVS) compared to standard medical care in COPD patients with severe emphysema.

METHODS

Patients with severe airflow obstruction, hyperinflation, and severe dyspnea with interlobar fissure integrity were evaluated for enrollment. A total of 107 subjects were randomized in a 2: 1 allocation ratio to either the treatment group (SVS valves and medical management) or the control group (medical management alone).

RESULTS

The 3-month primary endpoint showed statistically significant improvement in forced expiratory volume in 1 s in the treatment group compared to the control group (0.104 ± 0.18 vs. 0.003 ± 0.15 L, p = 0.001), with the difference being durable through 6 months. Statistically significant target lobe volume reduction was achieved at 3 months (mean change 684.4 ± 686.7 mL) and through 6 months (757.0 ± 665.3 mL). Exercise function and quality of life measures improved in the treatment group, but showed a deterioration in the control group. The serious adverse event (SAE) rate was 33% in the treatment group and 24.2% in the control group. The predominance of SAEs were acute exacerbations of COPD in both groups. There was 1 death in the control group and no deaths in the treatment group.

CONCLUSION

The SVS represents a novel approach for the treatment of severe emphysema with a clinically acceptable risk-benefit profile.

Complications after bronchoscopic lung volume reduction

Bronchoscopic lung volume reduction (BLVR) has been demonstrated an efficient and safe alternative to surgery in multiple randomized trials and retrospective cohort studies. However, despite its minimal invasiveness BLVR is not without potential harm. Complications and their incidents differ significantly between the individual BLVR techniques (valves, coils, vapour or sealant) which are bearing varying device- and intervention-dependent risks. Interventional pulmonologists must be aware of potential side effects and their management to anticipate and ensure highest quality treatment of the severely ill emphysema patient.

Endoscopic approaches for treating emphysema

INTRODUCTION

Surgical treatment of severe pulmonary emphysema has so far been associated with relatively high perioperative morbidity and mortality. In the past two decades, novel approaches to lung volume reduction and alternative minimally invasive endoscopic techniques have been developed. This review presents the different techniques (blocking and nonblocking) available until present as well as the appropriate patient selection and possible complications. Areas covered: All available randomized controlled trials (RCTs) have been evaluated. The only blocking technique is the reversible valve implantation. It results in lobar volume reduction and clinical benefit in emphysema patients with absent interlobar collateral ventilation and its efficacy has been confirmed in various RCTs. Non-blocking techniques that are independent of collateral ventilation include the partially irreversible coil implantation leading to parenchymal compression, the irreversible bronchoscopic thermal vapor ablation, and the polymeric lung volume reduction both inducing inflammatory reaction. These methods have been up to date examined in a few RCTs only. Finally, the targeted lung denervation aims at sustainable bronchodilation by ablation of parasympathetic pulmonary nerves. Expert commentary: Future studies must address the predictors of clinical outcome as well as the reduction of complications to improve both outcome and safety.

Interventional pulmonology in chronic obstructive pulmonary disease

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) and emphysema are widespread diseases associated with progressive dyspnea because of airflow limitation and hyperinflation. Fundamental therapeutic strategies consist of pulmonary rehabilitation, pharmacotherapy, long-term oxygen therapy, noninvasive ventilation, and surgical therapeutic approaches.

RECENT FINDINGS

In the last 14 years, endoscopic therapeutic modalities emerged as a substantial part of severe COPD and emphysema treatment. Techniques of the endoscopic lung volume reduction (ELVR) aim at reduction of hyperinflation. Thereby, the reversible valve implantation of which the efficacy was confirmed in various randomized controlled trials (RCT) results in lobar volume reduction and clinical benefit in emphysema patients with absent interlobar collateral ventilation. Nonblocking ELVR methods that are independent of collateral ventilation include the partially irreversible coil implantation leading to parenchymal compression, the irreversible bronchoscopic thermal vapor ablation and polymeric lung volume reduction both inducing inflammatory reaction. The nonblocking methods have been examined in only a few RCTs. The targeted lung denervation as a novel bronchoscopic therapy for COPD patients aims at sustainable bronchodilation by ablation of parasympathetic pulmonary nerves.

SUMMARY

The review summarizes the various endoscopic treatment approaches for managment of COPD and emphysema, their mechanism of action, their complications and the current available results of the most important RCTs.

Clinical and radiological outcome following pneumothorax after endoscopic lung volume reduction with valves

INTRODUCTION

Valve implantation has evolved as a therapy for patients with advanced emphysema. Although it is a minimally invasive treatment, it is associated with complications, the most common being pneumothorax. Pneumothorax occurs due to the rapid target lobe volume reduction and may be a predictor of clinical benefit despite this complication.

OBJECTIVE

The objective of this study was to conduct an exploratory data analysis of patients who developed a pneumothorax following endoscopic valve therapy for emphysema.

MATERIALS AND METHODS

This study performed a retrospective evaluation of pneumothorax management and the impact of pneumothorax on clinical outcomes in 70 patients following valve therapy in 381 consecutive patients.

RESULTS

Pneumothorax rate following valve therapy was 18%. Pneumothorax management consisted of chest tube insertion, valve removal, and surgical intervention in 87% (61/70), 44% (31/70), and 19% (13/70) of the patients, respectively. Despite pneumothorax, patients experienced modest but significant improvements in lung function parameters (forced expiratory volume in 1 second: 55±148 mL, residual volume: -390±964 mL, total lung capacity: -348±876; all P<0.05). Persistent lobar atelectasis 3 months after recovering from pneumothorax, which was associated with relevant clinical improvement, was observed in only 21% (15/70) of the patients.

CONCLUSION

Pneumothorax is a frequent severe complication following valve therapy that requires further intervention. Nevertheless, the pneumothorax does not impair the clinical status in the majority of patients. Patients with lobar atelectasis benefit after recovering from pneumothorax in terms of lung function parameters.