RESUMO
The evolution of T cell molecular signatures in the distal lung of patients with severe pneumonia is understudied. Here, we analyzed T cell subsets in longitudinal bronchoalveolar lavage fluid samples from 273 patients with severe pneumonia, including unvaccinated patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or with respiratory failure not linked to pneumonia. In patients with SARS-CoV-2 pneumonia, activation of interferon signaling pathways, low activation of the NF-κB pathway and preferential targeting of spike and nucleocapsid proteins early after intubation were associated with favorable outcomes, whereas loss of interferon signaling, activation of NF-κB-driven programs and specificity for the ORF1ab complex late in disease were associated with mortality. These results suggest that in patients with severe SARS-CoV-2 pneumonia, alveolar T cell interferon responses targeting structural SARS-CoV-2 proteins characterize individuals who recover, whereas responses against nonstructural proteins and activation of NF-κB are associated with poor outcomes.
RESUMO
Bronchoscopic lung volume reduction (BLVR) is an established treatment modality for the management of advanced chronic obstructive pulmonary disease complicated by severe emphysema and hyperinflation refractory to other therapies. BLVR aims to reduce hyperinflation and residual volume, thereby improving pulmonary function, symptom control, and quality of life. Multiple distinct devices and technologies, including endobronchial coils, thermal vapor ablation, bio-lung volume reduction, and airway bypass stenting, have been developed to achieve lung volume reduction with varying degrees of accessibility and evidence. The most promising BLVR treatment modality to date has been the placement of one-way endobronchial valves (EBVs), with more than 25,000 cases performed worldwide. Identifying symptomatic patients who would benefit from BLVR is challenging and can be time and resource intensive, and candidacy may be limited by physiologic parameters. Additional new technologies may be able to improve the identification and evaluation of candidates as well as increase the portion of evaluated patients who ultimately qualify for BLVR. In this review, we aim to provide historical context to BLVR, summarize the available evidence regarding its use, discuss potential complications, and provide readers with a clear guide to patient selection and referral for BLVR, with a focus on EBV placement. In addition, we will highlight potential future directions for the field.
RESUMO
Background: The management of massive hemoptysis is a high-risk, low-volume procedure that is associated with high mortality rates, and pulmonary and critical care medicine (PCCM) fellows often lack training. Simulation-based mastery learning (SBML) is an educational strategy that improves skill but has not been applied to massive hemoptysis management. Objective: This pilot study aimed to develop a high-fidelity simulator, implement an SBML curriculum, and evaluate the impact on PCCM fellows managing massive hemoptysis. Methods: We modified a simulator to bleed from segmental airways. Next, we developed an SBML curriculum and a validated 26-item checklist and set a minimum passing standard (MPS) to assess massive hemoptysis management. A cohort of traditionally trained providers was assessed using the checklist. First-year PCCM fellows reviewed a lecture before a pretest on the simulator using the skills checklist and underwent rapid-cycle deliberate practice with feedback. Subsequently, fellows were posttested on the simulator, with additional training as necessary until the MPS was met. We compared pretest and posttest performance and also compared SBML-trained fellows versus traditionally trained providers. Results: The MPS on the checklist was set at 88%. All first-year PCCM fellows (N = 5) completed SBML training. Mean checklist scores for SBML participants improved from 67.7 ± 8.4% (standard deviation) at pretest to 84.6 ± 6.7% at the initial posttest and 92.3 ± 5.4% at the final (mastery) posttest. Traditionally trained participants had a mean test score of 60.6 ± 13.1%. Conclusion: The creation and implementation of a massive hemoptysis simulator and SBML curriculum was feasible and may address gaps in massive hemoptysis management training.
RESUMO
BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause severe respiratory failure leading to prolonged mechanical ventilation. Data are just emerging about the practice and outcomes of tracheostomy in these patients. We reviewed our experience with tracheostomies for SARS-CoV-2. METHODS: We retrospectively reviewed the demographics, comorbidities, timing of mechanical ventilation, tracheostomy, and intensive care unit and hospital lengths of stay in SARS-CoV-2 patients who received tracheostomies performed by the interventional pulmonary team. A tertiary care, teaching hospital in Chicago, Illinois. From March 2020 to April 2021, our center had 473 patients intubated for SARS-CoV-2, and 72 (15%) had percutaneous bedside tracheostomy performed by the interventional pulmonary team. RESULTS: Median time from intubation to tracheostomy was 20 (interquartile range: 16 to 25) days. Demographics and comorbidities were similar between early and late tracheostomy, but early tracheostomy was associated with shorter intensive care unit lengths of stay and a shorter total duration of ventilation. To date, 39 (54%) patients have been decannulated, 17 (24%) before hospital discharge; median time to decannulation was 22 (IQR: 18 to 36) days. Patients that were decannulated were younger (56 vs. 69 y). The rate of decannulation for survivors was 82%. No providers developed symptoms or tested positive for SARS-CoV-2. CONCLUSION: Tracheostomy enhances care for patients with prolonged respiratory failure from SARS-CoV-2 since early tracheostomy is associated with shorter duration of critical care, and decannulation rates are high for survivors. It furthermore appears safe for both patients and operators.
Assuntos
COVID-19 , Insuficiência Respiratória , Humanos , SARS-CoV-2 , Traqueostomia/efeitos adversos , Estudos Retrospectivos , Respiração Artificial , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Unidades de Terapia IntensivaRESUMO
Tissue availability remains an important limitation of single-cell genomic technologies for investigating cellular heterogeneity in human health and disease. BAL represents a minimally invasive approach to assessing an individual's lung cellular environment for diagnosis and research. However, the lack of high-quality, healthy lung reference data is a major obstacle to using single-cell approaches to study a plethora of lung diseases. Here, we performed single-cell RNA sequencing on over 40,000 cells isolated from the BAL of four healthy volunteers. Of the six cell types or lineages we identified, macrophages were consistently the most numerous across individuals. Our analysis confirmed the expression of marker genes defining cell types despite background signals because of the ambient RNA found in many single-cell studies. We assessed the variability of gene expression across macrophages and defined a distinct subpopulation of cells expressing a set of genes associated with Macrophage Inflammatory Protein 1 (MIP-1). RNA in situ hybridization and reanalysis of published lung single-cell data validated the presence of this macrophage subpopulation. Thus, our study characterizes lung macrophage heterogeneity in healthy individuals and provides a valuable resource for future studies to understand the lung environment in health and disease.
Assuntos
Proteínas Inflamatórias de Macrófagos , Macrófagos , Humanos , Proteínas Inflamatórias de Macrófagos/genética , Líquido da Lavagem Broncoalveolar , Voluntários Saudáveis , RNARESUMO
Pathogen clearance and resolution of inflammation in patients with pneumonia require an effective local T cell response. Nevertheless, local T cell activation may drive lung injury, particularly during prolonged episodes of respiratory failure characteristic of severe SARS-CoV-2 pneumonia. While T cell responses in the peripheral blood are well described, the evolution of T cell phenotypes and molecular signatures in the distal lung of patients with severe pneumonia caused by SARS-CoV-2 or other pathogens is understudied. Accordingly, we serially obtained 432 bronchoalveolar lavage fluid samples from 273 patients with severe pneumonia and respiratory failure, including 74 unvaccinated patients with COVID-19, and performed flow cytometry, transcriptional, and T cell receptor profiling on sorted CD8+ and CD4+ T cell subsets. In patients with COVID-19 but not pneumonia secondary to other pathogens, we found that early and persistent enrichment in CD8+ and CD4+ T cell subsets correlated with survival to hospital discharge. Activation of interferon signaling pathways early after intubation for COVID-19 was associated with favorable outcomes, while activation of NF-κB-driven programs late in disease was associated with poor outcomes. Patients with SARS-CoV-2 pneumonia whose alveolar T cells preferentially targeted the Spike and Nucleocapsid proteins tended to experience more favorable outcomes than patients whose T cells predominantly targeted the ORF1ab polyprotein complex. These results suggest that in patients with severe SARS-CoV-2 pneumonia, alveolar T cell interferon responses targeting structural SARS-CoV-2 proteins characterize patients who recover, yet these responses progress to NF-κB activation against non-structural proteins in patients who go on to experience poor clinical outcomes.
RESUMO
The use of mechanical circulatory support (MCS) devices continues to expand in cases of refractory cardiogenic shock. Bleeding is one of the most common complications associated with MCS, and management can be challenging due to need for systemic anticoagulation. Significant hemoptysis can be a devastating complication. We describe a case of a patient supported by a right ventricular assist device with an oxygenator and a left ventricular assist device who developed pulmonary hemorrhage that was successfully treated with nebulized tranexamic acid (TXA). Following a 5-day treatment course, bleeding resolved, no adverse side effects were noted, and systemic anticoagulation was resumed.
Assuntos
Coração Auxiliar , Ácido Tranexâmico , Anticoagulantes , Coração Auxiliar/efeitos adversos , Hemoptise/complicações , Hemoptise/tratamento farmacológico , Hemorragia/complicações , Humanos , Choque Cardiogênico/tratamento farmacológico , Choque Cardiogênico/etiologia , Ácido Tranexâmico/uso terapêuticoRESUMO
BACKGROUND: SARS-CoV-2 can cause severe respiratory failure leading to prolonged mechanical ventilation. Data are just emerging about the practice and outcomes of tracheostomy in these patients. We reviewed our experience with tracheostomies for SARS-CoV-2 at our tertiary-care, urban teaching hospital. METHODS: We reviewed the demographics, comorbidities, timing of mechanical ventilation, tracheostomy, and ICU and hospital lengths-of-stay (LOS) in SARS-CoV-2 patients who received tracheostomies. Early tracheostomy was considered <14 days of ventilation. Medians with interquartile ranges (IQR) were calculated and compared with Wilcoxon rank sum, Spearman correlation, Kruskal-Wallis, and regression modeling. RESULTS: From March 2020 to January 2021, our center had 370 patients intubated for SARS-CoV-2, and 59 (16%) had percutaneous bedside tracheostomy. Median time from intubation to tracheostomy was 19 (IQR 17 - 24) days. Demographics and comorbidities were similar between early and late tracheostomy, but early tracheostomy was associated with shorter ICU LOS and a trend towards shorter ventilation. To date, 34 (58%) of patients have been decannulated, 17 (29%) before hospital discharge; median time to decannulation was 24 (IQR 19-38) days. Decannulated patients were younger (56 vs 69 years), and in regression analysis, pneumothorax was associated was associated with lower decannulation rates (OR 0.05, 95CI 0.01 - 0.37). No providers developed symptoms or tested positive for SARS-CoV-2. CONCLUSIONS: Tracheostomy is a safe and reasonable procedure for patients with prolonged SARS-CoV-2 respiratory failure. We feel that tracheostomy enhances care for SARS-CoV-2 since early tracheostomy appears associated with shorter duration of critical care, and decannulation rates appear high for survivors.
RESUMO
Some patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) develop severe pneumonia and acute respiratory distress syndrome1 (ARDS). Distinct clinical features in these patients have led to speculation that the immune response to virus in the SARS-CoV-2-infected alveolus differs from that in other types of pneumonia2. Here we investigate SARS-CoV-2 pathobiology by characterizing the immune response in the alveoli of patients infected with the virus. We collected bronchoalveolar lavage fluid samples from 88 patients with SARS-CoV-2-induced respiratory failure and 211 patients with known or suspected pneumonia from other pathogens, and analysed them using flow cytometry and bulk transcriptomic profiling. We performed single-cell RNA sequencing on 10 bronchoalveolar lavage fluid samples collected from patients with severe coronavirus disease 2019 (COVID-19) within 48 h of intubation. In the majority of patients with SARS-CoV-2 infection, the alveolar space was persistently enriched in T cells and monocytes. Bulk and single-cell transcriptomic profiling suggested that SARS-CoV-2 infects alveolar macrophages, which in turn respond by producing T cell chemoattractants. These T cells produce interferon-γ to induce inflammatory cytokine release from alveolar macrophages and further promote T cell activation. Collectively, our results suggest that SARS-CoV-2 causes a slowly unfolding, spatially limited alveolitis in which alveolar macrophages containing SARS-CoV-2 and T cells form a positive feedback loop that drives persistent alveolar inflammation.
Assuntos
COVID-19/imunologia , COVID-19/virologia , Macrófagos Alveolares/imunologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , SARS-CoV-2/patogenicidade , Linfócitos T/imunologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , COVID-19/genética , Estudos de Coortes , Humanos , Interferon gama/imunologia , Interferons/imunologia , Interferons/metabolismo , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Pneumonia Viral/genética , RNA-Seq , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Análise de Célula Única , Linfócitos T/metabolismo , Fatores de TempoRESUMO
BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic raised concern for exposure to healthcare providers through aerosol generating procedures, such as bronchoalveolar lavage (BAL). Current society guidelines recommended limiting use of BAL to reduce operators' risk for infection, yet data on the infection rate for providers after BAL is sparse. Since March 2020, our institution used a modified protocol to perform over 450 BALs on intubated COVID-19 patients. We therefore sought to describe the subsequent infectious risks to providers associated with BAL. METHODS: Fifty-two pulmonary and critical care providers (faculty and fellows) at our tertiary-care, urban medical center were surveyed. Survey participants were asked to provide the number of BALs on COVID-19 patients they performed, the number of weeks they cared for intensive care unit (ICU) patients with COVID-19, and the results of any SARS-CoV-2 testing that they received. Participants were asked to assess the difficulty of BAL on intubated COVID-19 patients as compared to routine ICU BAL using a numeric perceived difficulty score ranging from 1 (easier) to 10 (harder). RESULTS: We received forty-seven responses from fifty-two surveyed (90% response rate), with 2 declining to participate. Many respondents (19/45, 42%) spent >5 weeks on an ICU service with COVID-19 patients. The number of BALs performed by providers ranged from 0 to >60. Sixteen of the 35 providers (46%) who performed BALs underwent at least one nasopharyngeal (NP) swab to test for SARS-CoV-2, but none were positive. Twenty-seven of the 35 providers (77%) who performed BALs underwent SARS-CoV-2 serology testing, and only one (3.7%) was positive. Respondents indicated occasionally not being able to follow aerosol-minimizing steps but overall felt BALs in COVID-19 patients was only slightly more difficult than routine ICU BAL. DISCUSSION: At a high-volume center having performed >450 BALs on intubated COVID-19 patients with aerosol-limiting precautions, our survey of bronchoscopists found no positive NP SARS-CoV-2 tests and only one positive antibody test result. While the optimal role for COVID-19 BAL remains to be determined, these data suggest that BAL can be safely performed in intubated COVID-19 patients if experienced providers take precautions to limit aerosol generation and wear personal protective equipment.
RESUMO
Some patients infected with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) develop severe pneumonia and the acute respiratory distress syndrome (ARDS) [1]. Distinct clinical features in these patients have led to speculation that the immune response to virus in the SARS-CoV-2-infected alveolus differs from other types of pneumonia [2]. We collected bronchoalveolar lavage fluid samples from 86 patients with SARS-CoV-2-induced respiratory failure and 252 patients with known or suspected pneumonia from other pathogens and subjected them to flow cytometry and bulk transcriptomic profiling. We performed single cell RNA-Seq in 5 bronchoalveolar lavage fluid samples collected from patients with severe COVID-19 within 48 hours of intubation. In the majority of patients with SARS-CoV-2 infection at the onset of mechanical ventilation, the alveolar space is persistently enriched in alveolar macrophages and T cells without neutrophilia. Bulk and single cell transcriptomic profiling suggest SARS-CoV-2 infects alveolar macrophages that respond by recruiting T cells. These T cells release interferon-gamma to induce inflammatory cytokine release from alveolar macrophages and further promote T cell recruitment. Our results suggest SARS-CoV-2 causes a slowly unfolding, spatially-limited alveolitis in which alveolar macrophages harboring SARS-CoV-2 transcripts and T cells form a positive feedback loop that drives progressive alveolar inflammation. This manuscript is accompanied by an online resource: https://www.nupulmonary.org/covid-19/. ONE SENTENCE SUMMARY: SARS-CoV-2-infected alveolar macrophages form positive feedback loops with T cells in patients with severe COVID-19.
RESUMO
Macrophages are often viewed through the lens of their core functions, but recent transcriptomic studies reveal them to be largely distinct across tissue types. While these differences appear to be shaped by their local environment, the key signals that drive these transcriptional differences remain unclear. Since Wnt signaling plays established roles in cell fate decisions, and tissue patterning during development and tissue repair after injury, we consider evidence that Wnt signals both target and are affected by macrophage functions. We propose that the Wnt gradients present in developing and adult tissues effectively shape macrophage fates and phenotypes. We also highlight evidence that macrophages, through an ability to dispatch Wnt signals, may couple tissue debridement and matrix remodeling with stem cell activation and tissue repair.
Assuntos
Diferenciação Celular/imunologia , Macrófagos/imunologia , Células-Tronco/imunologia , Via de Sinalização Wnt/imunologia , Animais , Humanos , beta Catenina/imunologiaRESUMO
BACKGROUND: Mirabegron, a ß3 adrenergic receptor agonist, is FDA approved for treatment of overactive bladder. Approved in 2012 in the US, there have been no reports of any effects of mirabegron on pulmonary function. CASE PRESENTATION: We report the case of a 65 year old male with a history of Parkinson's disease, OSA, and aspiration pneumonia presenting with subacute worsening dyspnea and found to have worsening restrictive ventilatory defect with a pattern consistent with neuromuscular weakness. After recalling that initiation of mirabegron correlated with onset of his worsening symptoms, the patient decided to perform a trial period off the drug. He subsequently reported prompt improvement in his respiratory symptoms, which was confirmed objectively by pulmonary function tests. In this case, mirabegron was temporally associated with subacute worsening of the patient's pulmonary restrictive physiology, with subsequent resolution after discontinuation of the medication. CONCLUSIONS: The mechanism of this adverse effect is unknown, but we speculate that this effect may be potentially mediated by the effect of ß3 adrenergic receptor agonism on skeletal muscle, in this case in a patient with pre-existing neuromuscular disease. Careful assessment of patients who develop shortness of breath while on mirabegron should include an assessment for restrictive lung disease secondary neuromuscular dysfunction. Additional study is needed of the effects of ß3 agonism on skeletal muscle.
RESUMO
Idiopathic pulmonary fibrosis (IPF) and other forms of lung fibrosis are age-associated diseases with increased deposition of mesenchymal collagen that promotes respiratory malfunction and eventual death from respiratory failure. Our understanding of the pathobiology underlying pulmonary fibrosis is incomplete and current therapies available to slow or treat lung fibrosis are limited. Evidence reviewed herein demonstrates key involvement of mitochondrial dysfunction in diverse pulmonary cell populations, including alveolar epithelial cells (AEC), fibroblasts, and macrophages and/or immune cells that collectively advances the development of pulmonary fibrosis. The mitochondria have an important role in regulating whether fibrogenic stimuli results in the return of normal healthy function ("friend") or the development of pulmonary fibrosis ("foe"). In particular, we summarize the evidence suggesting that AEC mitochondrial dysfunction is important in mediating lung fibrosis signaling via mechanisms involving imbalances in the levels of reactive oxygen species, endoplasmic reticulum stress response, mitophagy, apoptosis and/or senescence, and inflammatory signaling. Further, we review the emerging evidence suggesting that dysfunctional mitochondria in AECs and other cell types play crucial roles in modulating nearly all aspects of the 9 hallmarks of aging in the context of pulmonary fibrosis as well as some novel molecular pathways that have recently been identified. Finally, we discuss the potential translational aspects of these studies as well as the key knowledge gaps necessary for better informing our understanding of the pathobiology of the mitochondria in mediating pulmonary fibrosis. We reason that targeting deficient mitochondria-derived pathways may provide innovative future treatment strategies that are urgently needed for lung fibrosis.