Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are progressive and debilitating diseases characterized by gradual obstruction of the pulmonary vasculature, leading to elevated pulmonary artery pressure (PAP) and increased pulmonary vascular resistance (PVR). If untreated, they can result in death due to right-sided heart failure. Riociguat is a novel soluble guanylate cyclase (sGC) stimulator that is approved for the treatment of PAH and CTEPH. We describe in detail the role of the nitric oxide-sGC-cyclic guanosine monophosphate (cGMP) signaling pathway in the pathogenesis of PAH and CTEPH and the mode of action of riociguat. We also review the preclinical data associated with the development of riociguat, along with the efficacy and safety data of riociguat from initial clinical trials and pivotal phase III randomized clinical trials in PAH and CTEPH.

Cesarean sections (CS) are believed to be associated with greater risks of postpartum VTE. Our objective was to systematically review the evidence on this association and on the absolute risk of VTE following CS.

The beneficial effects of smoking cessation on the progression of COPD are well established. Nevertheless, many patients with COPD continue to smoke.

Short-term anticoagulant treatment for acute DVT or pulmonary embolism (PE) effectively reduces the risk of recurrent disease during the first 6 to 12 months of therapy. Continued anticoagulation often is not instituted because of the perception among physicians that the risk of major bleeding will outweigh the risk of new venous thrombotic episodes.

Opioid use for chronic pain analgesia, particularly chronic noncancer pain, has increased greatly since the late 1990s, resulting in an increase in opioid-associated morbidity and mortality. A clear link between opioid use and sleep-disordered breathing (SDB) has been established, with the majority of chronic opioid users being affected by the condition, and dose-dependent severity apparent for some opioids. More evidence is currently needed on how to effectively manage opioid-induced SDB. This review summarizes the current state of knowledge relating to management of patients undergoing chronic opioid therapy who have SDB. Initial management of these patients requires a thorough biopsychosocial assessment of their need for opioid therapy, consideration of reduction or cessation of the opioid if possible, and analysis of alternative therapies for treatment of their pain. If opioid therapy must be continued, then management of the associated SDB may be important. Several small- to medium-scale studies have examined the efficacy of noninvasive ventilation, particularly adaptive servo-ventilation (ASV) for the treatment of opioid-associated SDB. This research is particularly important because opioids predispose predominantly to central sleep apnea and also, to a lesser extent, OSA. Generally, these studies have found positive results in treating opioid-associated SDB with ASV in terms of improving outcome measures such as central apnea index and the apnea-hypopnea index. Larger studies that measure longer term health outcomes, patient sleepiness, and compliance are needed, however. Registries of health outcomes of ASV-treated patients may assist with future treatment planning.

Current functional assessments do not allow a reliable assessment of small airways, which are a major site of disease in COPD. Single-breath washout (SBW) tests are feasible and reproducible methods for evaluating small airway disease. Their relevance in COPD remains unknown.

Cystic lung disease (CLD) in Sjögren syndrome (SS) is a condition with unclear prognostic implications. Our objectives in this study are to determine its frequency, progression over time, and associated risk factors and complications.

Geographic clusters in prevalence and hospitalizations for COPD have been identified at national, state, and county levels. The study objective is to identify county-level geographic accessibility to pulmonologists for adults with COPD.

Pleurodesis performed either by pleurectomy or pleural abrasion is recommended in the approach to primary spontaneous pneumothorax to avoid recurrence. However, the efficacy of parietal pleural abrasion in producing pleurodesis is questioned. This study aims to determine the efficacy of apical abrasion alone, abrasion plus fibrin sealant application, and pleurectomy in producing pleurodesis in rabbits.

Bronchiolitis obliterans syndrome (BOS) remains a major complication after lung transplantation, causing significant morbidity and mortality in a majority of recipients. BOS is believed to be the clinical correlate of chronic allograft dysfunction, and is defined as an obstructive pulmonary function defect in the absence of other identifiable causes, mostly not amenable to treatment. Recently, it has become clear that BOS is not the only form of chronic allograft dysfunction and that other clinical phenotypes exist; however, we focus exclusively on BOS. Radiologic findings typically demonstrate air trapping, mosaic attenuation, and hyperinflation. Pathologic examination reveals obliterative bronchiolitis lesions and a pure obliteration of the small airways (< 2 mm), with a relatively normal surrounding parenchyma. In this review, we highlight recent advances in diagnosis, pathologic examination, and risk factors, such as microbes, viruses, and antibodies. Although the pathophysiological mechanisms remain largely unknown, we review the role of the airway epithelium and inflammation and the various experimental animal models. We also clarify the clinical and therapeutic implications of these findings. Although significant progress has been made, the exact pathophysiological mechanisms and adequate therapy for posttransplantation BOS remain unknown, highlighting the need for further research to improve long-term posttransplantation BOS-free and overall survival.

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.

Pulmonary hypertension (PH) is an increasingly recognized cause of morbidity and mortality, and in the past 20 years, there has been a rapid expansion in research and available therapies. Although it is defined quite simply as a mean pulmonary arterial pressure of ≥ 25 mm Hg, PH encompasses a heterogeneous group of disease processes. In the past, PH was classified as primary or secondary, but as understanding of the various contributing diseases has increased, classification systems have attempted to group these diseases by clinical features and disease mechanism. The evaluation of patients with suspected PH can be cumbersome, and a careful and methodical approach is needed to ensure timely and accurate diagnosis, correct physiological classification, and appropriate treatment. In this review, we discuss the classification and diagnostic evaluation of PH in adults as well as some of the billing and coding considerations involved in this evaluation.

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Crit Care Med, 43 (2015) 263, http://dx.doi.org/10.1097/01.ccm.0000474875.35054.b3. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

This article provides an update on progress toward establishing pulmonary and critical care medicine (PCCM) fellowship training as one of the first four subspecialties to be recognized and supported by the Chinese government. Designed and implemented throughout 2013 and 2014 by a collaborative effort of the Chinese Thoracic Society (CTS) and the American College of Chest Physicians (CHEST), 12 leading Chinese hospitals enrolled a total of 64 fellows into standardized PCCM training programs with common curricula, educational activities, and assessment measures. Supplemental educational materials, online assessment tools, and institutional site visits designed to evaluate and provide feedback on the programs' progress are being provided by CHEST. As a result of this initial progress, the Chinese government, through the Chinese Medical Doctor's Association, endorsed the concept of subspecialty fellowship training in China, with PCCM as one of the four pilot subspecialties to be operationalized nationwide in 2016, followed by implementation across other subspecialties by 2020. This article also reflects on the achievements of the training sites and the challenges they face and outlines plans to enhance and expand PCCM training and practice in China.

Cysts are commonly seen on CT scans of the lungs, and diagnosis can be challenging. Clinical and radiographic features combined with a multidisciplinary approach may help differentiate among various disease entities, allowing correct diagnosis. It is important to distinguish cysts from cavities because they each have distinct etiologies and associated clinical disorders. Conditions such as emphysema, and cystic bronchiectasis may also mimic cystic disease. A simplified classification of cysts is proposed. Cysts can occur in greater profusion in the subpleural areas, when they typically represent paraseptal emphysema, bullae, or honeycombing. Cysts that are present in the lung parenchyma but away from subpleural areas may be present without any other abnormalities on high-resolution CT scans. These are further categorized into solitary or multifocal/diffuse cysts. Solitary cysts may be incidentally discovered and may be an age related phenomenon or may be a remnant of prior trauma or infection. Multifocal/diffuse cysts can occur with lymphoid interstitial pneumonia, Birt-Hogg-Dubé syndrome, tracheobronchial papillomatosis, or primary and metastatic cancers. Multifocal/diffuse cysts may be associated with nodules (lymphoid interstitial pneumonia, light-chain deposition disease, amyloidosis, and Langerhans cell histiocytosis) or with ground-glass opacities (Pneumocystis jirovecii pneumonia and desquamative interstitial pneumonia). Using the results of the high-resolution CT scans as a starting point, and incorporating the patient's clinical history, physical examination, and laboratory findings, is likely to narrow the differential diagnosis of cystic lesions considerably.

Testosterone replacement therapy (TRT) prescriptions have increased several-fold in the last decade. There have been concerns regarding a possible increased incidence of DVT and pulmonary embolism (PE) with TRT. Few data support the association between TRT and DVT/PE. We evaluated the incidence of DVT and PE in men who were prescribed TRT for low serum total testosterone (sTT) levels.