Diagnostic Performance and Safety Profile of Robotic-assisted Bronchoscopy: A Systematic Review and Meta-Analysis.

Rationale: Conventional electromagnetic navigation bronchoscopy and other guided bronchoscopic modalities have a very desirable safety profile, but their diagnostic yield is only 60-70% for pulmonary lesions. Recently, robotic-assisted bronchoscopy (RAB) platforms have been introduced to improve the diagnostic performance of bronchoscopic modalities. Objectives: To determine the diagnostic performance and safety profile of RAB (using shape-sensing and electromagnetic navigation-based platforms) by performing a systematic review and meta-analysis. Methods: The PubMed, Embase, and Google Scholar databases were searched to find studies that reported on the diagnostic performance and/or the safety profile of one of the RAB systems. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analysis was performed using MedCalc version 20.118. Pooled diagnostic yield was calculated using a Freeman-Tukey transformation. We planned to use a random-effects model if the I2 index was >40%. Results: Twenty-five studies were included: 20 including diagnostic and safety analyses and 5 including only safety analyses. The pooled diagnostic yield of RAB (20 studies, 1,779 lesions) was 84.3% (95% confidence interval, 81.1-87.2%). The I2 index was 65.6%. On the basis of our subgroup analyses, the heterogeneity was likely driven by differences in study designs (prospective vs. retrospective) and procedural protocols (such as different RAB systems). Lesion size > 2 cm, the presence of a computed tomography bronchus sign, and concentric radial endobronchial ultrasound view were associated with a statistically significant increase in the odds of diagnosis with RAB. The overall rates of pneumothorax, need for tube thoracostomy, and significant hemorrhage were 2.3%, 1.2%, and 0.5%, respectively. Conclusions: RAB systems have significantly increased the diagnostic yield of navigational bronchoscopy compared with conventional systems such as electromagnetic navigation bronchoscopy, but well-designed prospective studies are needed to better understand the impact of various factors, such as the use of three-dimensional imaging modalities, cryobiopsy, and specific ventilatory protocols, on the diagnostic yield of RAB.

Current Practices in Airway Stent Management: A National Survey of US Practitioners.

BACKGROUND: Despite a growing number of tracheobronchial stent types and indications, complications remain frequent, and high-quality evidence on practices to prevent stent-related complications is lacking. Understanding current management practice is a first step to designing prospective studies to assess whether specific practices aimed at mitigating stent-related complications improve patient-centered outcomes. OBJECTIVES: In this study, we aimed to understand current management strategies following tracheobronchial stenting. METHOD: We performed a nationwide survey of members of the American Association of Bronchology and Interventional Pulmonology (AABIP) and the General Thoracic Surgical Club (GTSC) who place airway stents. The electronic survey captured data on practitioners' demographics, practice setting, airway stent volume, and standard post-stent practices (if any) including the use of medications, mucus clearance devices, surveillance imaging, and surveillance bronchoscopy. RESULTS: One hundred thirty-eight physicians completed the survey. Respondents were majority male (75.4%) and had diverse training (50.0% completed interventional pulmonary fellowship; 18.1% thoracic surgery; 31.9% other stent training). Post-stent management strategies varied markedly across respondents; 75.4% prescribe at least one medication to prevent post-stent complications, 52.9% perform routine surveillance bronchoscopy in asymptomatic patients, 26.1% prescribe mucus clearance regimens, 16.7% obtain routine computed tomography scans in asymptomatic patients, and 8.3% routinely replace their stents prior to stent failure. CONCLUSIONS: In this national survey of practitioners who place airway stents, there was marked heterogeneity in post-stent management approaches. Further studies are needed to identify which, if any, of these strategies improve patient-centered outcomes.

Safety of Transbronchial Biopsies in Patients with Pulmonary Hypertension: Systematic Review and Meta-Analysis.

Rationale: Transbronchial lung biopsies (TBLBs) are commonly performed by pulmonologists. Most providers consider pulmonary hypertension to be at least a relative contraindication to TBLB. This practice is based primarily on expert opinion, as there are very few patient outcomes data backing it. Objectives: We performed a systematic review and meta-analysis of previously published studies to determine the safety of TBLB in patients with pulmonary hypertension. Methods: The MEDLINE, Embase, Scopus, and Google Scholar databases were searched for pertinent studies. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Meta-analysis was performed using MedCalc version 20.118 to calculate the weighted pooled relative risk of complications in patients with pulmonary hypertension. Results: Nine studies with a total of 1,699 patients were included in the meta-analysis. On the basis of the Newcastle-Ottawa Scale, the risk of bias was low in the included studies. The overall weighted relative risk of bleeding with TBLB in patients with pulmonary hypertension was 1.01 (95% confidence interval, 0.71-1.45) compared with patients without pulmonary hypertension. Heterogeneity was low; therefore, the fixed-effects model was used. In a subgroup analysis of three studies, the overall weighted relative risk of significant hypoxia in patients with pulmonary hypertension was 2.06 (95% confidence interval, 1.12-3.76). Conclusions: Our results show that the patients with pulmonary hypertension do not have a significantly elevated risk of bleeding with TBLB compared with control subjects. We hypothesize that significant postbiopsy bleeding might be preferentially originating from bronchial artery circulation as opposed to pulmonary artery circulation, much like episodes of massive spontaneous hemoptysis. This hypothesis can explain our results, as in this scenario, elevated pulmonary arterial pressure would not be expected to have a bearing on the risk of post-TBLB bleeding. Most of the studies in our analysis included patients with mild to moderate pulmonary hypertension and it is not clear if our results can be extrapolated to patients with severe pulmonary hypertension. We noted that the patients with pulmonary hypertension were at a higher risk of developing hypoxia and needing a longer duration of mechanical ventilation with TBLB compared with control subjects. Further studies are needed to better understand the origin and pathophysiology of post-TBLB bleeding.

Pleuroscopy or video-assisted thoracoscopic surgery for exudative pleural effusion: a comparative overview.

Exudative pleural effusions, such as malignant and tuberculous pleural effusions, are associated with notable morbidity and mortality. Unfortunately, a significant number of these effusions will remain undiagnosed despite thoracentesis. Traditionally, closed pleural biopsies have been the next best diagnostic step, but the diagnostic yield of blind closed pleural biopsies for malignant pleural effusions is insufficient. When image-guided targeted biopsies are not possible, both pleuroscopy and video-assisted thoracoscopic surgery are reasonable options for obtaining pleural biopsies, but the decision to select one procedure over the other continues to raise much debate. Pleuroscopy (aka. medical thoracoscopy, local anaesthetic thoracoscopy) is a relatively common procedure performed by interventional pulmonologists in the bronchoscopy suite with local anesthesia, often as an outpatient procedure, on spontaneously breathing patients. Video-assisted thoracoscopic surgery, on the other hand, is performed by thoracic surgeons in the operating room, on mechanically ventilated patients under general anesthesia, though admittedly considerable overlap exists in practice. Both pleuroscopy and video-assisted thoracoscopic surgery have reported diagnostic yields of over 90%, although pleuroscopy more often leads to the unsatisfactory diagnosis of 'non-specific' pleuritis. These cases of 'non-specific' pleuritis need to be followed up for at least one year, as 10-15% of them will eventually lead to the diagnosis of cancer, typically malignant pleural mesothelioma. Both procedures have their pros and cons, and it is therefore of paramount importance that all cases be discussed as part of a multidisciplinary approach to diagnosis within a "pleural team" that should ideally include interventional pulmonologists and thoracic surgeons.

Orphan Lung Diseases.

There are hundreds of rare orphan lung diseases. We have highlighted five of them, one from each of the five major categories of pulmonary disorders: pleuroparenchymal fibroelastosis (a rare diffuse parenchymal lung disease), pulmonary alveolar proteinosis (a rare autoimmune and diffuse parenchymal lung disease), lymphangioleiomyomatosis (a rare cystic lung disease), yellow nail syndrome (a rare pleural disease), and Mounier-Kuhn syndrome (a rare airway disorder). The pathogenesis, clinical presentation, diagnostic criteria, treatment options, and prognosis of each disorder is discussed. This review is by no means exhaustive and further research is needed to improve our understanding of these disorders.

Pleuroparenchymal fibroelastosis (PPFE) treated with lung transplantation and review of the literature.

A 26-year-old woman presented with a 15-year history of non-progressive dyspnoea. Chest imaging showed bilateral apical pleural and parenchymal scarring, pleural thickening and bronchiectasis. Pulmonary function tests showed a moderate restrictive defect. Non-invasive workup was non-revealing; therefore, the patient was referred for video-assisted thoracic surgery and lung biopsy. Histopathology revealed pleural thickening and, subpleural parenchymal fibrosis and elastic tissue deposition. Lung parenchyma further away from the pleura was well preserved. Based on these findings, the patient was diagnosed with pleuroparenchymal fibroelastosis (PPFE). Since PPFE is a progressive disorder without effective medical therapies, and given our patient's worsening symptoms, she underwent bilateral lung transplantation. It has been almost 4 years since the lung transplantation, our patient continues to do well. To the best of our knowledge, to date, this is the longest follow-up reported for a PPFE patient undergoing lung transplantation.

Palliative Care and Interventional Pulmonology.

Since pulmonary pathologies, such as lung cancer and chronic obstructive pulmonary disease (COPD), are some of the leading causes of morbidity and mortality around the world, pulmonologists are likely to encounter patients with unmet palliative care needs. This article focuses on the symptoms and complications encountered by patients with terminal pulmonary conditions, briefly describes the non-interventional palliative strategies, and then discusses more advanced therapies available in the realm of interventional pulmonology. Most of the literature discussed here is derived from patients with lung cancer and COPD.

Tumour necrosis factor (TNF) inhibitor-induced isolated pleural granulomas: a rare adverse effect.

A 53-year-old man with a history of Crohn's disease on infliximab, presented with several weeks of cough and dyspnoea. He had a right-sided pleural effusion, found to be exudative with lymphocytic predominance. He underwent right-sided video-assisted thoracic surgery (VATS) with biopsies and pleurodesis. Histopathology showed pleural-based non-caseating granulomas with unremarkable lung parenchyma. Cultures were only positive for Propionibacterium acnes 8 months later, he was found to have a left-sided exudative, lymphocytic predominant pleural effusion. Left-sided VATS and biopsies again showed pleural-based non-caseating granulomas with normal lung parenchyma. Having ruled out an active infection and malignant lesions, we diagnosed infliximab-induced pleural granulomas. Infliximab was stopped. The patient continues to do well at 6 years of follow-up. We believe this is the first report of tumour necrosis factor (TNF) inhibitor-induced isolated pleural granulomas. P. acnes and cytokine imbalance might be responsible for the pathogenesis of TNF inhibitor-induced granulomas.

Unlikely culprit: congenital middle aortic syndrome diagnosed in the sixth decade of life.

A 58-year-old woman was admitted with acute heart failure. She had a long history of resistant hypertension, with an unremarkable work up for secondary causes in the past. Her brachial blood pressure was 210/70 mm Hg, with ankle blood pressure of 100/70 mm Hg. CT angiogram revealed marked narrowing of the descending thoracic aorta between the left subclavian artery and the diaphragm, consistent with middle aortic syndrome (MAS). She was initially managed with diuretics and antihypertensives. Subsequently thoracotomy revealed a severely hypoplastic segment of the descending aorta. The diseased segment was resected and aortic reconstruction performed. Histopathology showed fragmentation of the medial elastic fibres and fibrosis of the medial and intimal layers. These findings along with gross aortic hypoplasia and absence of features of Takayasu's arteritis, suggest that our patient had congenital MAS. The patient has done well since her surgery. We believe this is the first case of congenital MAS reported in the sixth decade of life.

Giant cell myocarditis: a life-threatening disorder heralded by orbital myositis.

A 40-year-old man with a history of orbital myositis (OM) presented to the emergency department with ventricular tachycardia requiring electrical cardioversion. Postcardioversion ECG showed right bundle branch block, while an echocardiogram revealed an ejection fraction of 20% and a dilated right ventricle. Cardiac MRI produced suboptimal images because the patient was having frequent arrhythmias. The rest of the work up, including coronary angiography, was unremarkable. Given the dilated right ventricle, we suspected arrhythmogenic right ventricular cardiomyopathy and discharged the patient with an implantable cardioverter-defibrillator. 1 week later, he was readmitted with cardiogenic shock; endomyocardial biopsy revealed giant cell myocarditis (GCM). To the best of our knowledge, this is the seventh case report of GCM described in a patient with OM. We recommend that clinicians maintain a high degree of suspicion for GCM in patients with OM presenting with cardiac problems.