The anatomic location of small airways, the distribution of airway cartilage, and their correlation with ageing have not been well elucidated. The objective of this article was to explore the morphologic characteristics of small airways in vivo, and how airway structural changes correlate with age using endobronchial optical coherence tomography (EB-OCT).

Neutrophil extracellular traps (NETs) are extrusions of intracellular DNA and attached granular material that enable bacterial killing. NETs are increasingly recognized for their role in the pathogenesis of respiratory disease. NETs are composed of a complex mix of intracellularly derived material that neutrophils organize within the cytoplasm and then expel in a nondirected manner in the vicinity of invading organisms. Combined, these trap and destroy multiple genera of microbes including bacteria, fungi, viruses, and protozoans, limiting infection especially where phagocytosis is not possible. At first, NET formation was thought to be a terminal event for neutrophils; however, it is now apparent that some neutrophils survive this process, becoming anuclear, and may drive ongoing tissue damage. NETs are now known to be directly cytotoxic to lung epithelium and endothelium, and their excessive production is seen in pneumonia and acute lung injury as well as several chronic diseases, including COPD, asthma, and cystic fibrosis. NETs also appear to play a role in both tumor defense and dissemination, depending on the local microenvironment and the specific tumor subtype. It is becoming increasingly apparent that NET formation can exert a positive or negative influence on multiple respiratory pathologies and that simply globally reducing or increasing NET formation is unlikely to be a therapeutic success. Rather, as our understanding grows, it is likely that targeted NET up- or downregulation along with destruction or protection of already formed NETs may become an additional point of intervention for respiratory physicians.

This article reviews four key clinician strategies to improve the care of adult patients receiving supplemental oxygen in the outpatient setting in the United States. The current barriers to adequate oxygen services are substantial and complex and include decreased reimbursement to durable medical equipment (DME) companies; a substantially lower number of available DME suppliers; difficult communication with DME suppliers; rigid patient testing, prescription, and documentation requirements; and unclear patient benefit and adherence. Recent data documenting frequent and varied problems reflect the significant impact of supplemental oxygen therapy on patients and caregivers. Areas where clinicians can improve patient oxygen experiences are highlighted in this review and include understanding Centers for Medicare and Medicaid Services oxygen prescription requirements, matching oxygen equipment to patient needs, providing essential patient education, and understanding mechanisms for patients and clinicians to report unresolved oxygen problems.

Pulmonary arterial hypertension (PAH) is a chronic disease that ultimately progresses to right-sided heart failure (HF) and death. Close monitoring of pulmonary artery pressure (PAP) and right ventricular (RV) function allows clinicians to appropriately guide therapy. However, the burden of commonly used methods to assess RV hemodynamics, such as right heart catheterization, precludes frequent monitoring. The CardioMEMS HF System (Abbott) is an ambulatory implantable hemodynamic monitor, previously only used in patients with New York Heart Association (NYHA) class III HF. In this study, we evaluate the feasibility and early safety of monitoring patients with PAH and right-sided HF using the CardioMEMS HF System.

Since the first description of mechanical ventilation, our understanding of the positive and negative effects of this form of life support has continued to evolve. To maintain "normal" aeration of the lungs and "normal" blood gas measurements, patients often require much higher airway pressures and tidal volumes than would be expected in a healthy, spontaneously breathing adult. In the early days of mechanical ventilation, the goal was to normalize the blood gas levels, but over the last several decades, we have developed a much better appreciation for the deleterious effects of mechanical ventilation. We have found that lower tidal volumes, which may actually worsen oxygenation and reduce clearance of CO2, can decrease the level of harm caused by mechanical ventilation. This scenario is best described and agreed upon in the setting of ARDS, but a growing body of evidence suggests that the use of higher tidal volumes is harmful in patients with normal lungs undergoing general anesthesia or in patients with lung diseases other than ARDS requiring mechanical ventilation. Finally, the concept of self-induced lung injury has emerged as a mechanism through which patients generating large negative intrathoracic pressures to achieve larger tidal volumes can contribute to worsened lung injury. Given a growing supportive evidence base, we suggest that efforts be made to achieve low tidal volume ventilation in all patients with lung injury or undergoing mechanical ventilation for any reason.

Chronic inflammatory diseases of the lung are often life-threatening and are a leading cause of morbidity in our communities. MicroRNAs (miRs) are now recognized to play critical roles in a wide range of cellular functions, including the regulation of immunologic processes, which are often dysregulated in chronic respiratory diseases. These small noncoding RNA molecules regulate networks of genes by inhibiting translation through the targeting of one or multiple messenger RNA transcripts. This review highlights discoveries that identify important roles for miRs in the regulation of specific pathogenic features of a range of diseases. Furthermore, experimental evidence suggests that pharmacologic inhibition of miR function or delivery of mimics may have therapeutic potential. The review also therefore discusses the potential utility and limitations of therapeutically targeting these molecules and their downstream pathways.

Point-of-care ultrasonography is a key skill for the critical care clinician and is gaining widespread acceptance by clinicians in all areas of medicine. In addition to mastery of image acquisition, image interpretation, and clinical application, intensivists need to be adept with billing for their scanning activity. This article summarizes the requirements for documentation and image storage that must be met to obtain reimbursement for point-of-care ultrasonography services.

The direct-acting oral anticoagulants (DOACs) have been increasingly used over vitamin K antagonists in recent years because they do not require monitoring and have an immediate anticoagulation effect. In general, DOACs have exhibited a better safety profile and noninferiority for prophylaxis and treatment of venous thromboembolism (VTE) and stroke prevention in patients with atrial fibrillation compared with vitamin K antagonists in the non-ICU population; whether this finding holds true in patients who are critically ill remains unknown. The current review addresses the role of DOACs in special ICU populations, use of these agents for VTE prophylaxis, perioperative management of DOACs, drug monitoring, and potential drug interactions of DOACs in critically ill patients. Adverse events and available reversal agents for DOACs are also discussed.

The efficacy of azathioprine (AZA) and mycophenolate mofetil (MMF) for interstitial lung disease (ILD) has been described, but mainly in connective tissue disease-associated ILD. The objective of this study was to evaluate the effect of AZA and MMF on lung function and prednisone dose in myositis-related ILD (M-ILD).

An oronasal mask is frequently used to treat OSA. In contrast to nasal CPAP, the effectiveness of oronasal CPAP varies by unknown mechanisms. We hypothesized that oral breathing and pressure transmission through the mouth compromises oronasal CPAP efficacy.

Pulmonary embolism (PE) is one of the leading causes of death in hospitalized patients. Treatment patterns and patient demographics for PE are changing; therefore, we sought to evaluate national trends in admission rate, discharge disposition, and length of stay (LOS) in patients hospitalized with PE.