Advancements in airway stents: a comprehensive update

PURPOSE OF REVIEW

This review provides an overview of the evolving field of airway stenting (AS), highlighting its relevance in the management of central airway obstruction (CAO). It discusses recent advancements, including 3D-printed silicone stents (3DPSS), metallic stents, biodegradable stents (BS), and drug-eluting stents (DES), which are transforming clinical practice. The review underscores the ongoing challenges in patient selection, stent choice, and long-term management in the context of an evolving landscape.

RECENT FINDINGS

Innovations, particularly 3DPSS, have shown promise in providing patient-specific solutions. These stents offer improved symptom relief, enhanced quality of life, and lower complication rates, especially for complex airway diseases. The use of BS and DES is explored, raising prospects for future applications.

SUMMARY

The evolution of AS reflects a deepening understanding of airway obstructions. Recent innovations, such as 3DPSS, BS, and DES, show considerable promise in addressing the limitations of conventional stents. However, challenges related to complications, patient selection, and long-term management persist, demanding further research. Wide practice variations in the management of AS highlight the need for more clinical data and standardized guidelines. The search for the ideal stent continues, driven by the pursuit of better outcomes for patients with CAO.

Ergonomics of bronchoscopy: good advice or a pain in the neck?

Interventional pulmonologists require a unique set of skills including precise motor abilities and physical endurance, but surprisingly the application of ergonomic principles in the field of bronchoscopy remains limited. This is particularly intriguing when considering the significant impact that poor ergonomics can have on diagnostic aptitude, income potential and overall health. It is therefore imperative to provide comprehensive education to physicians regarding the significance of ergonomics in their work, especially considering the introduction of advanced diagnostic and therapeutic procedures. By implementing simple yet effective measures (e.g. maintaining neutral positions of the wrist, neck and shoulder; adjusting the height of tables and monitors; incorporating scheduled breaks; and engaging in regular exercises), the risk of injuries can be substantially reduced. Moreover, objective tools are readily available to assess ergonomic postures and estimate the likelihood of work-related musculoskeletal injuries. This review aims to evaluate the current literature on the impact of procedure-related musculoskeletal pain on practising pulmonologists and identify modifiable factors for future research.

Patient-specific airway stent using three-dimensional printing: a review

The primary function of an airway stent is to reestablish patency, impeding restenosis, supporting the tracheobronchial wall, or occluding fistulas. But stent-related complications are prevalent and can have devastating consequences. For this reason, stents are considered a last resort when there are no alternatives in treatment. Additionally, commercially available airway stents often poorly fit patients with complex airways, and they can cause various complications. At the end of the 20th century, three-dimensional (3D) printing technology was created. It has been transformative in healthcare and has been used in several applications. One of its first utilizations was the anatomical modeling of body structures that helps preoperative planning. In respiratory medicine, this technology has been essentially used in central airway diseases to produce 3D airway models and to create airway splints and prostheses. In the last decade, it has led to a transformation and allowed progress in personalized medicine, making patient-specific stents for individuals with complex airway problems. A patient-specific stent using 3D printing may minimize complications, improve quality of life, and reduce the need for repeated procedures. This review describes the recent advances in 3D printing technology, its use for developing airway prostheses to treat complex airway diseases, and the current evidence that supports its use.

Innovation in rigid bronchoscopy-past, present, and future

German laryngologist Gustav Killian performed the first "Direkte Bronchoskopie" using a rigid bronchoscope to extract a foreign airway body from the right main bronchus over a hundred years ago, transforming the practice of respiratory medicine. The procedure instantaneously became popular throughout the world. Chevalier Jackson Sr from the United States further advanced the instrument, technique, safety, and application. In the 1960s, Professors Harold H. Hopkins and N.S. Kapany introduced optical rods as well as fiberoptics that led Karl Storz to develop the cold light system improving endoluminal illumination, achievements that ushered in the modern era of flexible endoscopy. Several diagnostic and therapeutic procedures became possible such as transbronchial needle biopsy, transbronchial lung biopsy, airway electrosurgery, or cryotherapy. Dr. Jean-François Dumon from France advanced the use of Nd-YAG laser in the endobronchial tree and created the dedicated Dumon silicone stent introducing the whole new field of interventional pulmonology (IP). This major milestone revitalized interest in rigid bronchoscopy (RB). Now, advancements are being made in stenting, instrumentation, and education. RB robotic technology advancements are currently anticipated and can potentially revolutionize the practice of pulmonary medicine. In this review, we describe some of the most substantial advances related to RB from its beginning to the modern era.

Determination of patient-specific airway stent fit using novel 3D reconstruction measurement techniques: a 4-year follow-up of a patient

Managing complex benign airway disease is a major challenge in interventional pulmonology. With the introduction of additive manufacturing in the medical field, patient-specific (PS) implants are an innovate prospect for airway management. Historically, stents were oversized to resist migration. However, the optimal degree and impact of stent oversizing remains unclear. The ability to design stents based on computed tomography (CT) invites opportunity to understand sizing. Here, we report a novel three-dimensional (3D) image reconstruction tool to quantify fit repeatedly over time. Analysis of CT imaging before and after successive stent implants in a single patient with different areas of stenosis and malacia was done. Nine PS airway stents over 4 years (five left mainstem and four right mainstem) were studied. The distance between the airway model and stent was calculated. The CT images were correlated to stent designs in CloudCompare software (v2.10-alpha) for novel analysis. Heat map was exported depicting the distances between the airway and the stent to the clinician's prescribed stent model. Corresponding histograms containing distances, mean, and standard deviation were reported. It is possible to measure stent fit based on heat map quantification on patient imaging. Observation of the airway over time and stent change suggests that the airway became more open over time requiring increased stent diameters. The ability to design and measure stent fit over time can help quantify the utility and impact of PS silicone airway stent. The airway appears to display plasticity such that there is notable change in stent prescription over time.

Short-term Endoscopic Outcomes of Balloon and Rigid Bronchoplasty in the Management of Benign Subglottic and Tracheal Stenosis

BACKGROUND

Endoscopic therapies are firmly established in the management algorithm of benign subglottic and tracheal stenosis (SGTS). The optimal dilation strategy, however, has yet to be elucidated. The objective of this study was to compare the efficacy and safety of balloon versus rigid bronchoplasty in the treatment of benign SGTS.

METHODS

De novo cases of benign SGTS at our institution over a 9-year period were retrospectively identified. Patients were divided into 2 groups based on the initial dilation strategy of balloon or rigid bronchoplasty. Demographics, clinical findings, concurrent interventions, lesion characteristics, and complications were analyzed. Two reviewers independently assigned an index and follow-up endoscopic stenosis grade for each case. The mean stenosis grade at follow-up in both groups was then calculated and compared.

RESULTS

Sixty-three patients with benign SGTS were included. Most stenoses in the rigid (80%) and balloon (63%) bronchoplasty groups were complex ( P =0.174). In addition, 94% (59/63) of index stenoses were classified as Cotton Myer Grade 3. At follow-up, no significant difference was found in the mean stenosis grade between dilation strategies (1.97 vs. 2.2, P =0.287). Furthermore, no procedural-related complications were observed in either group.

CONCLUSION

Balloon and rigid bronchoplasty are safe and effective endoscopic tools in the early management of benign SGTS. A multimodality approach centered around mucosal sparing techniques remains vitally important to the overall and likely long-term success of treating this challenging disease entity.

Malignant Central Airway Obstruction: What's New?

Malignant central airway obstruction (MCAO) is a debilitating and life-limiting complication that occurs in an unfortunately large number of individuals with advanced intrathoracic cancer. Although the management of MCAO is multimodal and interdisciplinary, the task of providing patients with prompt palliation falls increasingly on the shoulders of interventional pulmonologists. While a variety of tools and techniques are available for the management of malignant obstructive lesions, advancements and evolution in this therapeutic venue have been somewhat sluggish and limited when compared with other branches of interventional pulmonary medicine (e.g., the early diagnosis of peripheral lung nodules). Indeed, one pragmatic, albeit somewhat uncharitable, reading of this article's title might suggest a wry smile and shug of the shoulders as to imply that relatively little has changed in recent years. That said, the spectrum of interventions for MCAO continues to expand, even if at a less impressive clip. Herein, we present on MCAO and its endoscopic and nonendoscopic management-that which is old, that which is new, and that which is still on the horizon.

Prospective cohort of cryobiopsy in interstitial lung diseases: a single center experience

Rationale

Transbronchial cryobiopsy has been increasingly used to diagnose interstitial lung diseases. However, there is uncertainty regarding its accuracy and risks, mainly due to a paucity of prospective or randomized trials comparing cryobiopsy to surgical biopsy.

Objectives

To evaluate the diagnostic yield and complications of cryobiopsy in patients selected by multidisciplinary discussion.

Methods

This was a prospective cohort from 2017 to 2019. We included consecutive patients with suspected interstitial lung diseases being considered for lung biopsy presented at our multidisciplinary meeting.

Measurements and main results

Of 112 patients, we recommended no biopsy in 31, transbronchial forceps biopsy in 16, cryobiopsy in 54 and surgical biopsy in 11. By the end of the study, 34 patients had had cryobiopsy and 24 patients, surgical biopsy. Overall pathologic and multidisciplinary diagnostic yield of cryobiopsy was 47.1% and 61.8%, respectively. The yield increased over time for both pathologic (year 1: 28.6%, year 2: 54.5%, year 3: 66.7%, p = 0.161) and multidisciplinary (year 1: 50%, year 2: 63.6%, year 3: 77.8%, p = 0.412) diagnosis. Overall rate of grade 4 bleeding after cryobiopsy was 11.8%. Cryobiopsy required less chest tube placement (11.8% vs 100%, p < 0.001) and less hospitalizations compared to surgical biopsy (26.5% vs 95.7%, p < 0.001), but hospitalized patients had a longer median hospital stay (2 days vs 1 day, p = 0.004).

Conclusions

Diagnostic yield of cryobiopsy increased over time but the overall grade 4 bleeding rate was 11.8%.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01990-4.

NAVIGATE 24-Month Results: Electromagnetic navigation bronchoscopy for pulmonary lesions at 37 centers in Europe and the United States

INTRODUCTION

Electromagnetic navigation bronchoscopy (ENB) is a minimally invasive, image-guided approach to access lung lesions for biopsy or localization for treatment. However, no studies have reported prospective 24-month follow-up from a large, multinational, generalizable cohort. This study evaluated ENB safety, diagnostic yield, and usage patterns in an unrestricted, real-world observational design.

METHODS

The NAVIGATE single-arm, pragmatic cohort study (NCT02410837) enrolled subjects at 37 academic and community sites in 7 countries with prospective 24-month follow-up. Subjects underwent ENB using the superDimension navigation system versions 6.3 to 7.1. The prespecified primary endpoint was procedure-related pneumothorax requiring intervention or hospitalization.

RESULTS

A total of 1,388 subjects were enrolled for lung lesion biopsy (1,329; 95.7%), fiducial marker placement (272; 19.6%), dye marking (23; 1.7%), and/or lymph node biopsy (36; 2.6%). Concurrent endobronchial ultrasound-guided staging occurred in 456 subjects. General anesthesia (78.2% overall, 56.6% Europe, 81.4% US), radial endobronchial ultrasound (50.6%, 4.0%, 57.4%), fluoroscopy (85.0%, 41.7%, 91.0%), and rapid on-site evaluation use (61.7%, 17.3%, 68.5%) differed between regions. Pneumothorax and bronchopulmonary hemorrhage occurred in 4.7% and 2.7% of subjects, respectively (3.2% [primary endpoint] and 1.7% requiring intervention or hospitalization). Respiratory failure occurred in 0.6%. The diagnostic yield was 67.8% (range 61.9%-70.7%; 55.2% Europe, 69.8% US). Sensitivity for malignancy was 62.6%. Lung cancer clinical stage was I-II in 64.7% (55.3% Europe, 65.8% US).

CONCLUSIONS

Despite a heterogeneous cohort and regional differences in procedural techniques, ENB demonstrates low complications and a 67.8% diagnostic yield while allowing biopsy, staging, fiducial placement, and dye marking in a single procedure.

A Blueprint for Success: A Multidisciplinary Approach to Clinical Operations within a Bronchoscopy Suite

Building an efficient facility for advanced bronchoscopic procedures involves many considerations. This review places particular emphasis on anesthesiology services, based on experience at a tertiary/quaternary care referral academic medical center. Topics include equipment requirements, applicable clinical standards and multidisciplinary collaboration. Patient flow arrangements for both outpatients and inpatients, from pre-operative care to discharge/disposition are highlighted. The importance of effective business planning, personnel training, leadership, communication, teambuilding, quality of care and patient safety are also discussed.

The Impact of Biopsy Tool Choice and Rapid On-Site Evaluation on Diagnostic Accuracy for Malignant Lesions in the Prospective: Multicenter NAVIGATE Study

BACKGROUND

The diagnostic yield of electromagnetic navigation bronchoscopy (ENB) is impacted by biopsy tool strategy and rapid on-site evaluation (ROSE) use. This analysis evaluates usage patterns, accuracy, and safety of tool strategy and ROSE in a multicenter study.

METHODS

NAVIGATE (NCT02410837) evaluates ENB using the superDimension navigation system (versions 6.3 to 7.1). The 1-year analysis included 1215 prospectively enrolled subjects at 29 United States sites. Included herein are 416 subjects who underwent ENB-aided biopsy of a single lung lesion positive for malignancy at 1 year. Use of a restricted number of tools (only biopsy forceps, standard cytology brush, and/or bronchoalveolar lavage) was compared with an extensive multimodal strategy (biopsy forceps, cytology brush, aspirating needle, triple needle cytology brush, needle-tipped cytology brush, core biopsy system, and bronchoalveolar lavage).

RESULTS

Of malignant cases, 86.8% (361/416) of true positive diagnoses were obtained using extensive multimodal strategies. ROSE was used in 300/416 cases. The finding of malignancy by ROSE reduced the total number of tools used. A malignant ROSE call was obtained in 71% (212/300), most (88.7%; 188/212) by the first tool used (49.5% with aspirating needle, 20.2% with cytology brush, 17.0% with forceps). True positive rates were highest for the biopsy forceps (86.9%) and aspirating needle (86.6%). Use of extensive tool strategies did not increase the rates of pneumothorax (5.5% restricted, 2.8% extensive) or bronchopulmonary hemorrhage (3.6% restricted, 1.1% extensive).

CONCLUSION

These results suggest that extensive biopsy tool strategies, including the aspirating needle, may provide higher true positive rates for detecting lung cancer without increasing complications.

Advanced Diagnostic and Therapeutic Bronchoscopy: Technology and Reimbursement

Advanced interventional pulmonary procedures of the airways, pleural space, and mediastinum continue to evolve and be refined. Health care, finance, and clinical professionals are challenged by both the indications and related coding complexities. As the scope of interventional pulmonary procedures expands with advanced technique and medical innovation, program planning and ongoing collaboration among clinicians, finance executives, and reimbursement experts are key elements for success. We describe advanced bronchoscopic procedures, appropriate Current Procedural Terminology coding, valuations, and necessary modifiers to fill the knowledge gap between basic and advanced procedural coding. Our approach is to balance the description of procedures with the associated coding in a way that is of use to the proceduralist, the coding specialist, and other nonclinical professionals.

Robotic Bronchoscopy for Peripheral Pulmonary Lesions: A Multicenter Pilot and Feasibility Study (BENEFIT)

Background

The diagnosis of peripheral pulmonary lesions (PPL) continues to present clinical challenges. Despite extensive experience with guided bronchoscopy, the diagnostic yield has not improved significantly. Robotic-assisted bronchoscopic platforms have been developed potentially to improve the diagnostic yield for PPL. Presently, limited data exist that evaluate the performance of robotic systems in live human subjects.

Research Question

What is the safety and feasibility of robotic-assisted bronchoscopy in patients with PPLs?

Study Design and Methods

This was a prospective, multicenter pilot and feasibility study that used a robotic bronchoscopic system with a mother-daughter configuration in patients with PPL 1 to 5 cm in size. The primary end points were successful lesion localization with the use of radial probe endobronchial ultrasound (R-EBUS) imaging and incidence of procedure related adverse events. Robotic bronchoscopy was performed in patients with the use of direct visualization, electromagnetic navigation, and fluoroscopy. After the use of R-EBUS imaging, transbronchial needle aspiration was performed. Rapid on-site evaluation (ROSE) was used on all cases. Transbronchial needle aspiration alone was sufficient when ROSE was diagnostic; when ROSE was not diagnostic, transbronchial biopsy was performed with the use of the robotic platform, followed by conventional guided bronchoscopic approaches at the discretion of the investigator.

Results

Fifty-five patients were enrolled at five centers. One patient withdrew consent, which left 54 patients for data analysis. Median lesion size was 23 mm (interquartile range, 15 to 29 mm). R-EBUS images were available in 53 of 54 cases. Lesion localization was successful in 51 of 53 patients (96.2%). Pneumothorax was reported in two of 54 of the cases (3.7%); tube thoracostomy was required in one of the cases (1.9 %). No additional adverse events occurred.

Interpretation

This is the first, prospective, multicenter study of robotic bronchoscopy in patients with PPLs. Successful lesion localization was achieved in 96.2% of cases, with an adverse event rate comparable with conventional bronchoscopic procedures. Additional large prospective studies are warranted to evaluate procedure characteristics, such as diagnostic yield.

Clinical Trial Registration

ClinicalTrials.gov; No.: NCT03727425; URL: www.clinicaltrials.gov.

Bronchoscopy challenges during the COVID-19 pandemic

Bronchoscopy is an aerosol-generating procedure that creates unique challenges for healthcare providers to reduce the potential spread of the COVID-19 respiratory pathogen. As part of the initial response, Cleveland Clinic postponed elective surgeries including bronchoscopy. We established a 5-tier system for prioritizing the urgency of bronchoscopy procedures. When elective bronchoscopies were resumed, we established protocols to reduce aerosolization and potential virus transmission risks such as using an airborne infection-isolation room and changing to total intravenous anesthesia. Also, we established guidelines for periprocedural care and use of personal protective equipment including requirements for wearing N95 masks for all bronchoscopy procedures.

Navigational bronchoscopy: a guide through history, current use, and developing technology

The peripheral pulmonary nodule offers unique challenges to the clinician, especially in regards to diagnostic approach. Quite often the etiology of the nodule is spurious, though the specter of malignancy drives accurate classification of the nodule. Diagnostic approaches range in degrees of invasiveness, accuracy, and morbidity. Bronchoscopic access to these nodules had been plagued by low reported yields, especially in fluoroscopically invisible nodules. Navigational bronchoscopy, however, allowed more accurate access to peripheral nodules while maintaining a low morbidity, and thus reshaped the historic diagnostic algorithms. Though navigational bronchoscopy was initially associated with electromagnetic navigation, newer approaches to navigation and new technologies provide enthusiasm that yield can improve. In this article we will provide a historical approach to navigational bronchoscopy, from its origins to its current state, and we will discuss developing technology and its potential role in the evolving paradigm of the peripheral nodule biopsy.

Bronchoscopic lung volume reduction with valves: What should the internist know?

Traditional therapies for emphysema such as bronchodilators and anti-inflammatory drugs have limited value due to permanent structural changes in the emphysematous lung that result in hyperinflation. Surgical lung volume reduction partially corrects hyperinflation by removing emphysematous lung and is an option in selected patients, but it carries a risk of morbidity and death. Valve therapy is a less-invasive option that involves bronchoscopic implantation of 1-way valves in emphysematous lung segments to allow air flow and mucus clearance in the direction of central airways. The authors review the rationale, evidence, and applications of valve therapy.

Accuracy of a Robotic Endoscopic System in Cadaver Models with Simulated Tumor Targets: ACCESS Study

BACKGROUND

Bronchoscopy for the diagnosis of peripheral pulmonary lesions continues to present clinical challenges, despite increasing experience using newer guided techniques. Robotic bronchoscopic platforms have been developed to potentially improve diagnostic yields. Previous studies in cadaver models have demonstrated increased reach into the lung periphery using robotic systems compared to similarly sized conventional bronchoscopes, although the clinical impact of additional reach is unclear.

OBJECTIVES

This study was performed to evaluate the performance of a robotic bronchoscopic system's ability to reach and access artificial tumor targets simulating peripheral nodules in human cadaveric lungs.

METHODS

Artificial tumor targets sized 10-30 mm in axial diameter were implanted into 8 human cadavers. CT scans were performed prior to procedures and all cadavers were intubated and mechanically ventilated. Electromagnetic navigation, radial probe endobronchial ultrasound, and fluoroscopy were used for all procedures. Robotic-assisted bronchoscopy was performed on each cadaver by an individual bronchoscopist to localize and biopsy peripheral lesions.

RESULTS

Sixty-seven nodules were evaluated in 8 cadavers. The mean nodule size was 20.4 mm. The overall diagnostic yield was 65/67 (97%) and there was no statistical difference in diagnostic yield for lesions <20 mm compared with lesions measuring 21-30 mm, the presence of a concentric or eccentric radial ultrasound image, or relative distance from the pleura.

CONCLUSIONS

The robotic bronchoscopic system was successful at biopsying 97% of peripheral pulmonary lesions 10-30 mm in size in human cadavers. These findings support further exploration of this technology in prospective clinical trials in live human subjects.

A Blueprint for Success: Design and Implementation of an Ideal Bronchoscopy Suite

Bronchoscopy is essential to the practice of pulmonary medicine. It is an important diagnostic and therapeutic tool for many disease processes. Bronchoscopy can be performed in a variety of clinical settings, from the bedside to an operating room. Although bronchoscopy has been practiced for more than a century, consensus recommendations from stakeholders have yet to be developed for the planning, implementation, and construction of a bronchoscopy suite. A wide range of procedures can be performed via bronchoscopy; therefore, the required tools and the procedure area must be aligned with the needs of the facility. Designing a bronchoscopy suite is by no means a "one size fits all" process. We present an overview of critical features to be considered in the planning for an ideal bronchoscopy suite. We use the term "ideal" because it represents a subjective conception of what is perfect and does not convey a rigid, universal blueprint.

3D printing for airway disease

It has been 30 years since the first commercial three-dimensional (3D) printer was available on market. The technological advancement of 3D printing has far exceeded its implementation in medicine. The application of 3D printing technology has the potential of playing a major role within interventional pulmonology; specifically, in the management of complex airway disease. Tailoring management to the patient-specific anatomical malformation caused by benign or malignant disease is a major challenge faced by interventional pulmonologists. Such cases often require adjunctive therapeutic procedures with thermal therapies followed by dilation and airway stenting to maintain the patency of the airway. Airway-stent size matching is one key to reducing stent-related complications. A major barrier to matching is the expansion of the stent in two dimensions (fixed sizes in length and diameter) within the deformed airway. Additional challenges are created by the subjective oversizing of the stent to reduce the likelihood of migration. Improper sizing adversely affects the stability of the stent. The stent-airway mismatch can be complicated by airway erosion, perforation, or the formation of granulation tissue. Stents can migrate, fracture, obstruct, or become infected. The use of patient-specific 3D printed airway stents may be able to reduce the stent airway mismatch. These stents allow more precise stent-airway sizing and minimizes high-pressure points on distorted airway anatomy. In theory, this should reduce the incidence of the well-known complications of factory manufactured stents. In this article, the authors present the brief history of 3D printed stents, their consideration in select patients, processing steps for development, and future direction.

State-of-the-Art Modalities for Peripheral Lung Nodule Biopsy

Lung nodules are being increasingly detected, particularly with lung cancer screening with low-dose computed tomography. Although the vast majority of lung nodules are benign, many often require tissue diagnosis. Several modalities to obtain diagnostic tissue from peripheral lung nodules are available. Bronchoscopic modalities such as radial ultrasound and electromagnetic navigational bronchoscopy are becoming increasingly used because of their superior safety profile and improving diagnostic yield. Although these modalities continue to become more advanced, newer and complementary technologies appear promising.

A retrospective analysis of delays in the diagnosis of lung cancer and associated costs

Purpose

Diagnosis of lung cancer at advanced stages can result in missed treatment opportunities, worse outcomes, and higher health care costs. This study evaluated the wait time to diagnose non-small-cell lung cancer (NSCLC) and the cost of diagnosis and treatment based on the stage at diagnosis.

Patients and methods

Adult patients diagnosed with NSCLC between January 2007 and September 2011 were identified from a proprietary oncology registry and linked to health insurance claims from a large US health insurance company. Continuous enrollment in the health plan was required for at least 12 months prediagnosis (baseline) and at least 3 months postdiagnosis (follow-up). Use of diagnostic tests and time to diagnosis were examined. The rates of health care utilization and per-patient per-month (PPPM) health care costs were calculated.

Results

A total of 1,210 patients with NSCLC were included in the analysis. Most patients (93.6%) had evidence of diagnostic tests beginning 5 to 6 months prior to diagnosis, and most were diagnosed at an advanced stage (23% Stage IIIb and 46% Stage IV). The PPPM total health care costs in USD pre- and postdiagnosis were $2,407±$3,364 (mean±standard deviation) and $16,577±$33,550, respectively. PPPM total health care costs and utilization after lung cancer diagnosis were significantly higher among patients diagnosed at Stage IV disease and lowest among patients diagnosed at Stage I disease ($7,239 Stage I, $9,484 Stage II, $11,193 Stage IIIa, $17,415 Stage IIIb, and $21,441 Stage IV).

Conclusion

This study showed that most patients experienced long periods of delay between their first diagnostic test for lung cancer and a definitive diagnosis, and the majority were diagnosed at advanced stages of disease. Costs associated with the management of lung cancer increased substantially with higher stages at diagnosis. Procedures that diagnose lung cancer at earlier stages may allow for less resource use and costs among patients with lung cancer.

Electromagnetic navigation bronchoscopy to access lung lesions in 1,000 subjects: first results of the prospective, multicenter NAVIGATE study

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB) is an image-guided, minimally invasive approach that uses a flexible catheter to access pulmonary lesions.

METHODS

NAVIGATE is a prospective, multicenter study of the superDimension™ navigation system. A prespecified 1-month interim analysis of the first 1,000 primary cohort subjects enrolled at 29 sites in the United States and Europe is described. Enrollment and 24-month follow-up are ongoing.

RESULTS

ENB index procedures were conducted for lung lesion biopsy (n = 964), fiducial marker placement (n = 210), pleural dye marking (n = 17), and/or lymph node biopsy (n = 334; primarily endobronchial ultrasound-guided). Lesions were in the peripheral/middle lung thirds in 92.7%, 49.7% were <20 mm, and 48.4% had a bronchus sign. Radial EBUS was used in 54.3% (543/1,000 subjects) and general anesthesia in 79.7% (797/1,000). Among the 964 subjects (1,129 lesions) undergoing lung lesion biopsy, navigation was completed and tissue was obtained in 94.4% (910/964). Based on final pathology results, ENB-aided samples were read as malignant in 417/910 (45.8%) subjects and non-malignant in 372/910 (40.9%) subjects. An additional 121/910 (13.3%) were read as inconclusive. One-month follow-up in this interim analysis is not sufficient to calculate the true negative rate or diagnostic yield. Tissue adequacy for genetic testing was 80.0% (56 of 70 lesions sent for testing). The ENB-related pneumothorax rate was 4.9% (49/1,000) overall and 3.2% (32/1,000) CTCAE Grade ≥2 (primary endpoint). The ENB-related Grade ≥2 bronchopulmonary hemorrhage and Grade ≥4 respiratory failure rates were 1.0 and 0.6%, respectively.

CONCLUSIONS

One-month results of the first 1,000 subjects enrolled demonstrate low adverse event rates in a generalizable population across diverse practice settings. Continued enrollment and follow-up are required to calculate the true negative rate and delineate the patient, lesion, and procedural factors contributing to diagnostic yield.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02410837 . Registered 31 March 2015.

Electromagnetic Navigational Bronchoscopy for Peripheral Pulmonary Nodules

Electromagnetic navigational bronchoscopy is a useful addition to the array of modalities available to sample peripheral lung lesions. Its utility in diagnosing peripheral lesions has been steadily increasing since the Food and Drug Administration first approved it in 2004. The improvement can be attributed to continuous refinement in technology, increasing training and experience with the procedure, perhaps widespread availability of rapid onsite cytologic evaluation, and better patient selection. It may also be attributable to improvements of the technology and more available tools to perform biopsy of the peripheral lung.

Endobronchial Ultrasound: Clinical Uses and Professional Reimbursements

Endobronchial ultrasonography (EBUS) has become an invaluable tool in the diagnosis of patients with a variety of thoracic abnormalities. The majority of EBUS procedures are used to diagnose and stage mediastinal and hilar abnormalities, as well as peripheral pulmonary targets, with a probe-based technology. Nearly 1,000 articles have been written about its use and utility. New Current Procedural Terminology (CPT) codes have been introduced in 2016 to better capture the work and clinical use associated with the various types of EBUS procedures. The existing 31620 code has been deleted and replaced by three new codes: 31652, 31653, and 31654. These new codes have been through the valuation process, and the new rule for reimbursement has been active since January 1, 2016 with National Correct Coding Initiative correction as of April 1, 2016. The impact of these new codes will result in a net reduction in professional and technical reimbursement. This article describes the current use of EBUS and explains the current codes and professional reimbursement.

Design of a prospective, multicenter, global, cohort study of electromagnetic navigation bronchoscopy

Background

Electromagnetic navigation bronchoscopy (ENB) procedures allow physicians to access peripheral lung lesions beyond the reach of conventional bronchoscopy. However, published research is primarily limited to small, single-center studies using previous-generation ENB software. The impact of user experience, patient factors, and lesion/procedural characteristics remains largely unexplored in a large, multicenter study.

Methods/Design

NAVIGATE (Clinical Evaluation of superDimension™ Navigation System for Electromagnetic Navigation Bronchoscopy) is a prospective, multicenter, global, cohort study. The study aims to enroll up to 2,500 consecutive subjects presenting for evaluation of lung lesions utilizing the ENB procedure at up to 75 clinical sites in the United States, Europe, and Asia. Subjects will be assessed at baseline, at the time of procedure, and at 1, 12, and 24 months post-procedure. The pre-test probability of malignancy will be determined for peripheral lung nodules. Endpoints include procedure-related adverse events, including pneumothorax, bronchopulmonary hemorrhage, and respiratory failure, as well as quality of life, and subject satisfaction. Diagnostic yield and accuracy, repeat biopsy rate, tissue adequacy for genetic testing, and stage at diagnosis will be reported for biopsy procedures. Complementary technologies, such as fluoroscopy and endobronchial ultrasound, will be explored. Success rates of fiducial marker placement, dye marking, and lymph node biopsies will be captured when applicable. Subgroup analyses based on geography, demographics, investigator experience, and lesion and procedure characteristics are planned.

Discussion

Study enrollment began in April 2015. As of February 19, 2016, 500 subjects had been enrolled at 23 clinical sites with enrollment ongoing. NAVIGATE will be the largest prospective, multicenter clinical study on ENB procedures to date and will provide real-world experience data on the utility of the ENB procedure in a broad range of clinical scenarios.

Trial registration

ClinicalTrials.gov NCT02410837. Registered 31 March 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0228-y) contains supplementary material, which is available to authorized users.

Parasitic Diseases of the Lung

Parasitic infection is a major healthcare problem that affects millions of the world’s population. Immigration and global warming have changed the natural distribution of parasitic diseases far removed from endemic areas. The respiratory system can be affected by a broad spectrum of helminthic and protozoal parasitic diseases. The diagnosis of parasitic infection of the respiratory system may be delayed due to myriad clinical and radiographic presentations of parasitic diseases which make the diagnosis of these entities challenging. Pulmonologists need to be familiar with the epidemiology, clinical presentation, pathophysiology, and bronchoscopic findings of parasitic lung diseases, in order to provide proper management in a timely fashion. This review provides a comprehensive view of both helminthic and protozoal parasitic diseases that affect the respiratory system, especially the central airways.

Complications Following Therapeutic Bronchoscopy for Malignant Central Airway Obstruction: Results of the AQuIRE Registry

BACKGROUND

There are significant variations in how therapeutic bronchoscopy for malignant airway obstruction is performed. Relatively few studies have compared how these approaches affect the incidence of complications.

METHODS

We used the American College of Chest Physicians (CHEST) Quality Improvement Registry, Evaluation, and Education (AQuIRE) program registry to conduct a multicenter study of patients undergoing therapeutic bronchoscopy for malignant central airway obstruction. The primary outcome was the incidence of complications. Secondary outcomes were incidence of bleeding, hypoxemia, respiratory failure, adverse events, escalation in level of care, and 30-day mortality.

RESULTS

Fifteen centers performed 1,115 procedures on 947 patients. There were significant differences among centers in the type of anesthesia (moderate vs deep or general anesthesia, P < .001), use of rigid bronchoscopy (P < .001), type of ventilation (jet vs volume cycled, P < .001), and frequency of stent use (P < .001). The overall complication rate was 3.9%, but significant variation was found among centers (range, 0.9%-11.7%; P = .002). Risk factors for complications were urgent and emergent procedures, American Society of Anesthesiologists (ASA) score > 3, redo therapeutic bronchoscopy, and moderate sedation. The 30-day mortality was 14.8%; mortality varied among centers (range, 7.7%-20.2%, P = .02). Risk factors for 30-day mortality included Zubrod score > 1, ASA score > 3, intrinsic or mixed obstruction, and stent placement.

CONCLUSIONS

Use of moderate sedation and stents varies significantly among centers. These factors are associated with increased complications and 30-day mortality, respectively.

Cost effectiveness of bronchial thermoplasty in patients with severe uncontrolled asthma

RATIONALE

Based on its clinical effectiveness, bronchial thermoplasty (BT) was approved by the Food and Drug Administration in 2010 for the treatment of severe persistent asthma in patients 18 years and older whose asthma is not well-controlled with inhaled corticosteroids and long-acting beta-agonist medicines.

OBJECTIVE

Assess the 10 year cost-effectiveness of BT for individuals with severe uncontrolled asthma.

METHODS

Using a Markov decision analytic model, the cost-effectiveness of BT was estimated. The patient population involved a hypothetical cohort of 41-year-old patients comparing BT to usual care over a 10-year time frame. The main outcome measure was cost in 2013 dollars per additional quality adjusted life year (QALY).

RESULTS

Treatment with BT resulted in 6.40 QALYs and $7512 in cost compared to 6.21 QALYs and $2054 for usual care. The incremental cost-effectiveness ratio for BT at 10 years was $29,821/QALY. At a willingness to pay per QALY of $50,000, BT continues to be cost effective unless the probability of severe asthma exacerbation drops below 0.63 exacerbation per year or the cost of BT rises above $10,384 total for all three bronchoscopic procedures needed to perform thermoplasty and to cover the entire bronchial tree (baseline = $6690).

CONCLUSIONS

BT is a cost-effective treatment for asthmatics at high risk of exacerbations. Continuing to follow asthmatics treated with BT beyond 5 years will help inform longer efficacy and support its cost-effectiveness.

Therapeutic bronchoscopy for malignant central airway obstruction: success rates and impact on dyspnea and quality of life

BACKGROUND

There is significant variation between physicians in terms of how they perform therapeutic bronchoscopy, but there are few data on whether these differences impact effectiveness.

METHODS

This was a multicenter registry study of patients undergoing therapeutic bronchoscopy for malignant central airway obstruction. The primary outcome was technical success, defined as reopening the airway lumen to > 50% of normal. Secondary outcomes were dyspnea as measured by the Borg score and health-related quality of life (HRQOL) as measured by the SF-6D.

RESULTS

Fifteen centers performed 1,115 procedures on 947 patients. Technical success was achieved in 93% of procedures. Center success rates ranged from 90% to 98% (P = .02). Endobronchial obstruction and stent placement were associated with success, whereas American Society of Anesthesiology (ASA) score > 3, renal failure, primary lung cancer, left mainstem disease, and tracheoesophageal fistula were associated with failure. Clinically significant improvements in dyspnea occurred in 90 of 187 patients measured (48%). Greater baseline dyspnea was associated with greater improvements in dyspnea, whereas smoking, having multiple cancers, and lobar obstruction were associated with smaller improvements. Clinically significant improvements in HRQOL occurred in 76 of 183 patients measured (42%). Greater baseline dyspnea was associated with greater improvements in HRQOL, and lobar obstruction was associated with smaller improvements.

CONCLUSIONS

Technical success rates were high overall, with the highest success rates associated with stent placement and endobronchial obstruction. Therapeutic bronchoscopy should not be withheld from patients based solely on an assessment of risk, since patients with the most dyspnea and lowest functional status benefitted the most.

Anesthesia for bronchoscopic amniotic membrane grafting to treat non-healing bronchial dehiscence

Airway complications after lung transplantation remain a significant cause of morbidity and mortality. Many of these occur at the anastomotic sites, which are susceptible due to poor collateral circulation. Of the possible complications, bronchial dehiscence is particularly formidable. These cases have been successfully treated bronchoscopically with metallic stents, which likely promote healing through granulation tissue formation. However, limited options exist in cases where the dehiscence fails to heal following stent placement. Here, we present the case report of a 65-year-old male who developed bronchial dehiscence status post bilateral lung transplantation for idiopathic pulmonary fibrosis that failed to heal with simple stent placement. Eventually, the patient underwent amniotic membrane grafting with stenting as a novel therapy for non-healing bronchial dehiscence, for which we describe the anesthetic management. His anesthetic plan included inhalational induction with sevoflurane, propofol infusion for total intravenous anesthesia, rocuronium for muscle relaxation, and closed-circuit assisted ventilation. His existing tracheostomy was used as the airway for oxygenation and induction. In summary, our anesthetic plan for the lung transplant patient was effective; future amniotic membrane grafting for bronchial dehiscence through bronchoscopy may follow a similar technique. Ultimately, the choice of anesthesia in this patient population requires judicious consideration of the requirements of the procedure as well as the pathophysiology of the transplanted lung.

Tracheobronchial smooth muscle atrophy and separation

We report a case series involving 4 patients with chronic obstructive pulmonary disease who were on an appropriate medical regimen including a high dose of inhaled corticosteroids (ICS). During bronchoscopy, patients were found to have an excessive dynamic collapse of the posterior wall and its separation from the ends of the adjacent cartilaginous rings. This was causing a near-total occlusion of the tracheal and bronchial lumen during exhalation, thereby presenting with an obstructive pattern on the pulmonary functions. We suspect that this was caused by the atrophy of the smooth muscles of the tracheobronchial wall. We reviewed the literature to explore the mechanisms causing atrophy of the bronchial smooth muscle, focusing on the potential role of long-term ICS use.

Utility of GATA3, mammaglobin, GCDFP-15, and ER in the detection of intrathoracic metastatic breast carcinoma

INTRODUCTION

Breast carcinoma (BC) metastatic to the intrathoracic cavity is difficult to diagnose due to low sensitivity of current immunohistochemical (IHC) stains. Mammaglobin, gross cystic disease fluid protein-15 (GCDFP-15), and estrogen receptor (ER) immunomarkers show variable results. GATA3 is a recently described marker for detecting urothelial and breast cancers. Our goal is to test the utility of GATA3 in cell blocks from thoracic cytology specimens.

MATERIALS AND METHODS

We retrieved cases of BC that metastasized to the thoracic cavity from January 1, 2005 to September 30, 2013. IHC was performed on the cell blocks for the presence of GATA3, ER, GCDFP-15, and mammaglobin. Stains were scored quantitatively and qualitatively.

RESULTS

Fifty cases of metastatic BC found in pleural effusions and endobronchial ultrasound-guided fine-needle aspirates were identified in 48 patients. Thirty-four cases had sufficient material for IHC (19 pleural effusions, 15 endobronchial ultrasound-guided fine-needle aspirates). GATA3 showed strong nuclear positivity in 31 of 34 cases (91.2%). ER (25 of 34, 73.5%), mammaglobin (23 of 34, 67.6%) and GCDFP-15 (11 of 34, 32.6%) were positive in fewer cases. GATA3 and ER were concordant in 26 of 34 cases (76.5%) (24 ER/GATA3-positive, 2 ER/GATA3-negative). Discordant results were found in 8 of 34 cases (23.5%). Of these, GATA3 was positive and ER was negative in 7 cases. GATA3 was negative and ER was positive in 1 case.

CONCLUSIONS

GATA3 is more sensitive than ER, mammaglobin, or GCDFP-15 in detecting metastatic BC in cytologic specimens. GATA3 may be positive when ER is negative. In cytologic specimens with limited diagnostic material, GATA3 may be used as a first-line marker in a limited IHC panel to support metastatic BC.

Electromagnetic navigation bronchoscopy-guided fine needle aspiration for the diagnosis of lung lesions

Many peripheral lung lesions are beyond the reach of conventional bronchoscopes, and require percutaneous CT-guided or open surgical biopsy, which carry increased risks to the patient. Electromagnetic navigation bronchoscopy (ENB) is a relatively new technique, which uses an image guided localization system to direct steerable bronchoscopic tools to predetermined points within the bronchial tree. This technology allows improved access to peripheral lesions in particular. We investigated the sensitivity and specificity of ENB-guided fine needle aspiration (FNA) in the diagnosis of lung lesions. All ENB-guided FNAs performed at one institution were included in the study. The superDimension i-Logic System™ was used in all cases. Pathologic reports of the ENB-guided FNAs, as well as all other pulmonary sampling performed simultaneously with the FNA and within 1 year of the ENB-guided FNA were reviewed. Patients with a positive ENB-guided FNA or malignancy within the same lobe within the follow-up period were considered positive for malignancy. Patients with an atypical diagnosis but no definitive malignancy were considered negative for malignancy for statistical purposes. Ninety-one patients underwent 95 ENB-guided FNAs over a 3-year period. Thirty-five patients (38%) were positive for malignancy. ENB-guided FNA had a sensitivity of 63% for the detection of malignancy. The sensitivity for the detection of malignancy using all ENB-guided sampling methods, including FNA, bronchoscopic biopsy, and bronchial brushing was 83%. Pathologists and cytotechnologists should be aware of ENB-guided FNA as an emerging technology with a relatively high sensitivity for the diagnosis of peripheral lung lesions.

Pulmonary disease in small-vessel vasculitis

Diagnosis of the pulmonary manifestations of small-vessel vasculitis requires attention to detail, judicious use of imaging technology, and awareness of disorders that can mimic or masquerade as pulmonary vasculitis. Treatment should begin with pharmacologic intervention to manage the underlying inflammatory disorder. Dilation procedures and, in rare cases, surgery may be needed to resolve airway stenosis.

Anesthesia for bronchoscopy

Bronchoscopic procedures are at times intricate and the patients often very ill. These factors and an airway shared with the pulmonologist present a clear challenge to anesthesiologists. The key to success lies in the understanding of both the underlying pathology and procedure being performed combined with frequent two-way communication between the anesthesiologist and the pulmonologist. Above all, vigilance and preparedness are paramount. Topics discussed in this review include anesthesia for advanced diagnostic procedures as well as for interventional/ therapeutic procedures. The latter includes bronchoscopic tracheal balloon dilation, tracheobronchial stenting, endobronchial electrocautery, bronchoscopic cryotherapy and other techniques. Special situations, such as tracheoesophageal fistula and mediastinal masses, are also considered.

Bronchial thermoplasty: a new treatment for severe refractory asthma

Bronchial thermoplasty was recently approved for treating severe refractory asthma that is not well controlled by high-dose inhaled corticosteroids and long-acting bronchodilator therapy. This article reviews its indications, evidence of efficacy, and protocols.

High dose-rate endobronchial radiotherapy for proximal airway obstruction due to lung cancer: 8-year experience of a referral center

The efficacy of high dose-rate endobronchial radiotherapy (HDERT) against proximal airway obstruction that results from lung cancer has not been thoroughly evaluated. This study retrospectively reviewed tumor/obstruction characteristics prior to therapy, interventions applied, symptoms before and after intervention, complications, and survival of all patients with proximal airway obstruction resulting from lung cancer who received HDERT between 1995 and 2003 in a tertiary teaching center. Thirty-four (34) patients received HDERT, while 28 had additional treatment (external radiotherapy = 23, neodymium yttrium aluminum garnet laser ablation = 9, stenting = 7, electrosurgery = 5, cryosurgery = 3, and photodynamic therapy = 1). Sixteen (16) patients developed complications, the most frequent being respiratory failure and bronchial-wall necrosis, while 19 experienced symptomatic relief. The median (95% confidence interval) survival of these 34 patients was 7.8 (5.9-9.8) months, significantly longer (p = 0.004) than a historic control of 3.9 (3.7-7.1) months from the Cleveland Clinic Foundation, in Cleveland, OH, and comparable to other previous reports. No single factor predicted complications or symptomatic relief. However, female gender, presence of only one symptom, absence of fatigue/weight loss, >1 HDERT sessions, and postprocedure symptom relief were associated with improved survival. Contemporary HDERT with or without additional treatment modalities is effective against central airway compromise resulting from lung cancer.

Anesthesia and airway management for removing pulmonary self-expanding metallic stents

The use of bronchoscopically placed self-expanding metallic stents (SEMS) and silastic stents in patients suffering from tracheobronchial stenosis or similar problems has proven to be an important clinical option. When complications occur, it may be necessary to remove the device. Removal of a SEMS is usually performed during general anesthesia with muscle relaxation and positive pressure ventilation, often using total intravenous anesthesia. Airway management depends on stent type and location. Intubating patients' tracheas with a tracheal stent requires special caution, as it risks damaging tissue and dislodging the stent distally. Potential complications with removal include tracheal disruption, retained stent pieces, mucosal tears, re-obstruction requiring new stent placement, the need for postoperative ventilation, pneumothorax, damage to the pulmonary artery, and death.