American Thoracic Society/European Respiratory Society Research Articles

Histological variability and consequences in chronic bird-related hypersensitivity pneumonitis.

Lobar and temporal histological variability in chronic bird-related hypersensitivity pneumonitis (BRHP) has not been clearly elucidated. This study was designed to evaluate the spatio-temporal histopathological variability in chronic BRHP. Fifty-two patients with chronic BRHP who underwent a surgical lung biopsy (SLB) between 1992 and 2008 were evaluated. The histopathological characteristics of the lung biopsy specimens were classified by the 2002 American Thoracic Society/European Respiratory Society (ATS/ERS) consensus classification of idiopathic interstitial pneumonias (IIPs). Autopsy specimens from seven patients were also evaluated to examine the serial changes from SLB to autopsy. In a study of lobar histological variability based on the findings of SLB, 7 patients were diagnosed with cellular nonspecific interstitial pneumonia (NSIP) pattern, 16 with fibrotic NSIP pattern, 20 with fibrotic NSIP pattern and usual interstitial pneumonia (UIP) (discordant UIP) pattern and 9 with UIP (concordant UIP) pattern. In a study of sequential changes, specimens of SLBs with fibrotic NSIP pattern changed to a bronchiolocentric interstitial pneumonia (BIP) pattern or UIP pattern. Interlobar and intralobar histological variability is present in chronic BRHP. In several patients with chronic BRHP, a fibrotic NSIP pattern may be an early lesion that progresses to a UIP pattern.

Análisis de presión inspiratoria máxima según tres protocolos en estudiantes voluntarios asintomáticos de la Universidad Católica del Maule, Chile

Maximum inspiratory pressure (MIP) has been used as an indicator of inspiratory muscle strength. Nevertheless their values show a high variability (~20%). The aim of this study was to determine the MIP, according to three protocols in young subjects. An observational cross-sectional study was carried out on a convenience sample of 60 students, 30 men (19.2 ± 0.81 years-old) and 30 women (19.17 ± 0.91 years-old). MIP was evaluated according to the protocol defined for each group of 20 participants of both genders: Group 1: American Thoracic Society/European Respiratory Society (ATS/ERS); Group 2: Learning; Group 3: Warming. For the analysis we used descriptive and inferential statistics, a p value < 0.05 was considered significant. No differences in MIP were found for the three best averages between groups (p = 0.078). When comparing the total performance of MIP replicates G3 was higher than G1 and G2 (p

Idiopathic Lymphoid Interstitial Pneumonia: A Case Report

Idiopathic Lymphoid Interstitial Pneumonia (LIP) is considered to be a rare interstitial lung disease. The initial American Thoracic Society/European Respiratory Society (ATS/ERS) International multidisciplinary consensus paper on Idiopathic Interstitial Pneumonia of 2002, LIP was classified as one of the seven major idiopathic interstitial lung diseases. Since the first description of LIP in 1969, so far only 14 biopsy proven cases of idiopathic LIP have been described in the literature. The clinical course is reported to be highly variable in this rare form of interstitial pneumonia.

Is the six-minute walk test a useful tool to prescribe high-intensity exercise in patients with chronic obstructive pulmonary disease?

BackgroundIt is not yet completely known whether the 6MWT can be used to prescribe high-intensity exercise for patients with COPD. ObjectiveTo evaluate the ability of the six-minute walk test (6MWT) to prescribe high-intensity exercise for patients with chronic obstructive pulmonary disease (COPD). MethodsLung function, maximal inspiratory strength, symptoms and exercise capacity were evaluated in patients with COPD (n = 27) before and after a 12-week high-intensity exercise program. Criteria for high-intensity training were: 1) ≥75% of the 6MWT average speed; 2) American Thoracic Society/European Respiratory Society (ATS/ERS) criteria (≥60% of the maximal incremental shuttle walk test speed). ResultsThe 6MWT showed good positive and negative predictive values (0.69 and 0.71, respectively), and accuracy (0.70), good reliability (ICC 0.70 [95%CI 0.45–0.85]) and moderate agreement (k 0.41 [95%CI 0.13–0.67]) with the ATS/ERS criteria. ConclusionThe 6MWT has good predictive ability and accuracy in relation to high-intensity exercise for patients with COPD.

Temperature-controlled laminar airflow in severe asthma for exacerbation reduction (The LASER Trial): study protocol for a randomised controlled trial

BackgroundAsthma affects more than 5 million patients in the United Kingdom. Nearly 500,000 of these patients have severe asthma with severe symptoms and frequent exacerbations that are inadequately controlled with available treatments. The burden of severe asthma on the NHS is enormous, accounting for 80 % of the total asthma cost (£1 billion), with frequent exacerbations and expensive medications generating much of this cost.Of those patients with severe asthma, 70 % are sensitised to indoor aeroallergens, and the level of exposure to allergens determines the symptoms; patients exposed to high levels are therefore most at risk of exacerbations and hospital admissions.The LASER trial aims to assess whether a new treatment, temperature controlled laminar airflow (TLA) delivered by the Airsonett™ device, can reduce the frequency of exacerbations in patients with severe allergic asthma by reducing exposure to aeroallergens overnight.MethodsThis multicentre study is a placebo-controlled, blinded, randomised controlled, parallel group trial. A total of 222 patients with a new or current diagnosis of severe allergic asthma will be assigned with a random element in a 1:1 ratio to receive either an active device for one year or a placebo device. The primary outcome is the frequency of severe asthma exacerbations occurring over a 12-month period, defined in accordance with the American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines. Secondary outcomes include changes in asthma control, lung function, asthma-specific and global quality of life for participants and their carers, adherence to intervention, healthcare resource use and costs, and cost-effectiveness. Qualitative interviews will be conducted to elicit participant’s and their partner’s perceptions of the treatment.DiscussionEffective measures of allergen avoidance have, to date, proved elusive. The LASER trial aims to address this. The study will ascertain whether home-based nocturnal TLA usage over a 12-month period can reduce the frequency of exacerbations and improve asthma control and quality of life as compared to placebo, whilst being cost-effective and acceptable to adults with poorly controlled, severe allergic asthma. The results of this study will be widely applicable to the many patients with allergic asthma both in the UK and internationally.Trial registrationCurrent controlled trials ISRCTN46346208 (Date assigned 22 January 2014).

American Thoracic Society-European Respiratory Society Classification of the Idiopathic Interstitial Pneumonias: Advances in Knowledge since 2002.

In the updated American Thoracic Society-European Respiratory Society classification of the idiopathic interstitial pneumonias (IIPs), the major entities have been preserved and grouped into (a) "chronic fibrosing IIPs" (idiopathic pulmonary fibrosis and idiopathic nonspecific interstitial pneumonia), (b) "smoking-related IIPs" (respiratory bronchiolitis-associated interstitial lung disease and desquamative interstitial pneumonia), (c) "acute or subacute IIPs" (cryptogenic organizing pneumonia and acute interstitial pneumonia), and (d) "rare IIPs" (lymphoid interstitial pneumonia and idiopathic pleuroparenchymal fibroelastosis). Furthermore, it has been acknowledged that a final diagnosis is not always achievable, and the category "unclassifiable IIP" has been proposed. The diagnostic interpretation of the IIPs is often challenging because other diseases with a known etiology (most notably, connective tissue disease and hypersensitivity pneumonitis) may show similar morphologic patterns. Indeed, more emphasis has been given to the integration of clinical, computed tomographic (CT), and pathologic findings for multidisciplinary diagnosis. Typical CT-based morphologic patterns are associated with the IIPs, and radiologists play an important role in diagnosis and characterization. Optimal CT quality and a systematic approach are both pivotal for evaluation of IIP. Interobserver variation for the various patterns encountered in the IIPs is an issue. It is important for radiologists to understand the longitudinal behavior of IIPs at serial CT examinations, especially for providing a framework for cases that are unclassifiable or in which a histologic diagnosis cannot be obtained.

Invited Commentary on "American Thoracic Society-European Respiratory Society Classification of the Idiopathic Interstitial Pneumonias".

Invited Commentary on "American Thoracic Society-European Respiratory Society Classification of the Idiopathic Interstitial Pneumonias".

Predictors of poor-quality spirometry in two cohorts of older adults in Russia and Belgium: a cross-sectional study.

Background:Spirometry is an important test for the diagnosis of respiratory diseases, yet it is underused especially in older adults. Several predictors of good-quality spirometry in this age group have been reported, based mainly on in/outpatients of geriatric and/or respiratory units.Aims:This study aims to assess predictors of poor-quality spirometry in community-dwelling older adults from two primary care cohorts in Russia and Belgium.Methods:Spirograms from two population-based cohort studies in Russia (CRYSTAL) and Belgium (BELFRAIL) were assessed in accordance with the American Thoracic Society/European Respiratory Society (ATS/ERS) acceptability and repeatability criteria and grouped into good and poor quality. Multivariable analysis assessed the association of poor-quality spirometry with socio-demographics, functional dependency, physical and mental functioning and co-morbidities.Results:In all, 43.3% of the 522 BELFRAIL participants (84.71±3.67 years old) and 57.7% of the 605 CRYSTAL participants (75.11±5.97 years old) achieved all ATS/ERS acceptability and repeatability criteria. In both cohorts, those with poor-quality spirometry had lower cognitive function (mini-mental state examination (MMSE) ⩽24). After adjustment in multivariable analysis, MMSE ⩽24 had an odds ratio for poor-quality spirometry of 1.33 (95% CI=0.78–2.28) in the BELFRAIL and 1.30 (95% CI=0.88–1.91) in the CRYSTAL cohort.Conclusions:In community-dwelling older adults, including those over 80 years old, impaired cognition measured by the MMSE may not be an independent predictor of poor-quality spirometry. Further research is needed in this area, and spirometry should be used more often in older adults in primary care.

Pharmacists performing quality spirometry testing: an evidence based review.

The scope of pharmacist services for patients with pulmonary disease has primarily focused on drug related outcomes; however pharmacists have the ability to broaden the scope of clinical services by performing diagnostic testing including quality spirometry testing. Studies have demonstrated that pharmacists can perform quality spirometry testing based upon international guidelines. The primary aim of this review was to assess the published evidence of pharmacists performing quality spirometry testing based upon American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines. In order to accomplish this, the description of evidence and type of outcome from these services were reviewed. A literature search was conducted using five databases [PubMed (1946-January 2015), International Pharmaceutical Abstracts (1970 to January 2015), Cumulative Index of Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews] with search terms including pharmacy, spirometry, pulmonary function, asthma or COPD was conducted. Searches were limited to publications in English and reported in humans. In addition, Uniform Resource Locators and Google Scholar searches were implemented to include any additional supplemental information. Eight studies (six prospective multi-center trials, two retrospective single center studies) were included. Pharmacists in all studies received specialized training in performing spirometry testing. Of the eight studies meeting inclusion and exclusion criteria, 8 (100%) demonstrated acceptable repeatability of spirometry testing based upon standards set by the ATS/ERS guidelines. Acceptable repeatability of seven studies ranged from 70 to 99% consistent with published data. Available evidence suggests that quality spirometry testing can be performed by pharmacists. More prospective studies are needed to add to the current evidence of quality spirometry testing performed by pharmacists and to measure health outcomes of the pulmonary patient.

Symptoms and markers of symptom severity in asthma--content validity of the asthma symptom diary.

Background and objectivesThe American Thoracic Society/European Respiratory Society (ATS/ERS) Task Force acknowledged the multi-faceted nature of asthma in its recent definition of asthma control as a summary term capturing symptoms, reliever use, frequency/severity of exacerbations, lung function, and future risk and the Global Initiative for Asthma (GINA) defines the clinical manifestations (well established markers of asthma severity) of asthma to include symptoms, sleep disturbances, limitations of daily activity, impairment of lung function, and use of rescue medications. The objectives of this qualitative work were to identify symptoms and markers of symptom severity relevant to patients with moderate to severe asthma and to evaluate the content validity of the asthma symptom diary (ASD).MethodsA qualitative interview study was conducted using a purposive sample of symptomatic adult and adolescent (≥12 years) subjects with asthma. Concept elicitation (CE) interviews (n = 50) were conducted to identify core asthma symptoms and symptom-related clinical markers, followed by cognitive interviews (n = 24) to ensure patient comprehension of the items, instructions and response options. CE interviews were coded using ATLAS.ti for content analysis.ResultsThe study sample had a diverse range of symptom severity, level of symptom control, sociodemographic and socioeconomic status. The most frequently reported symptoms in adults were chest tightness (n = 33/34; 97.1%), wheezing (n = 31; 91.2%), coughing (n = 30; 88.2%), and shortness of breath (n = 25; 73.5%); in adolescents they were wheezing (n = 14/16; 87.5%), coughing (n = 13; 81.3%), and chest tightness (n = 11; 68.8%). Adults identified chest tightness followed by shortness of breath as their most severe symptoms; while adolescents reported coughing and chest tightness as their most severe symptoms. Sleep awakenings and limitations in day-to-day activities were frequent symptom-related clinical markers. Day-to-day variability and differences between daytime and nighttime symptom experiences reported by subjects resulted in the need for the ASD to be administered twice daily. Cognitive interviews indicated that subjects found the revised ASD items clear and easy to understand.ConclusionsThis study supports the content validity of the revised ASD, showing it to be consistent with patient experiences and ready for further psychometric testing.

Pleuroparenchymal Fibroelastosis: A New Entity within the Spectrum of Rare Idiopathic Interstitial Pneumonias.

Pleuroparenchymal fibroelastosis (PPFE) is a rare entity that has been recently included in the official American Thoracic Society/European Respiratory Society (ATS/ERS) statement in 2013 as a group of rare idiopathic interstitial pneumonias (IIPs). PPFE is characterized by pleural and subpleural parenchymal thickening due to elastic fiber proliferation, mainly in the upper lobes. The etiology of the disease is unclear, although some cases have been associated as a complication after bone marrow transplantation, lung transplantation (LT), chemotherapy, and recurrent respiratory infections. The patients usually report progressive dyspnea and dry cough and are predisposed to develop spontaneous or iatrogenic pneumothoraces after surgical lung biopsy (SLB) for its diagnosis. That is why better awareness with the clinical and radiologic features can help optimal management by the multidisciplinary team. Novel invasive techniques such as cryobiopsy may become useful tools in these patients as it could spare SLB. We present the first reported cases in Spain.

Algorithm for automatic forced spirometry quality assessment: technological developments.

We hypothesized that the implementation of automatic real-time assessment of quality of forced spirometry (FS) may significantly enhance the potential for extensive deployment of a FS program in the community. Recent studies have demonstrated that the application of quality criteria defined by the ATS/ERS (American Thoracic Society/European Respiratory Society) in commercially available equipment with automatic quality assessment can be markedly improved. To this end, an algorithm for assessing quality of FS automatically was reported. The current research describes the mathematical developments of the algorithm. An innovative analysis of the shape of the spirometric curve, adding 23 new metrics to the traditional 4 recommended by ATS/ERS, was done. The algorithm was created through a two-step iterative process including: (1) an initial version using the standard FS curves recommended by the ATS; and, (2) a refined version using curves from patients. In each of these steps the results were assessed against one expert's opinion. Finally, an independent set of FS curves from 291 patients was used for validation purposes. The novel mathematical approach to characterize the FS curves led to appropriate FS classification with high specificity (95%) and sensitivity (96%). The results constitute the basis for a successful transfer of FS testing to non-specialized professionals in the community.

Rare idiopathic intestinal pneumonias (IIPs) and histologic patterns in new ATS/ERS multidisciplinary classification of the IIPs

The new American Thoracic Society/European Respiratory Society (ATS/ERS) update to the multidisciplinary classification of idiopathic interstitial pneumonias (IIPs) defines both rare IIPs and rare histologic patterns of IIPs. Although these diseases are rare, each has some distinguishing imaging and pathologic characteristics. Common findings for IIPs in computed tomography (CT) include cysts in lymphoid interstitial pneumonia (LIP), upper lobe subpleural consolidation in pleuropulmonary fibroelastosis (PPFE), symmetrical consolidation in acute fibrinous organizing pneumonia (AFOP), and peribronchovascular consolidation or centrilobular nodules in bronchiolocentric pattern of interstitial pneumonia.

Prevalence of Airflow Obstruction in U.S. Adults Aged 40–79 Years: NHANES Data 1988–1994 and 2007–2010

Background: The study evaluated the change in the prevalence of airflow obstruction in the U.S. population 40–79 years of age from years 1988–1994 to 2007–2010. Methods: Spirometry data from two representative samples of the U.S. population, the National Health and Nutrition Examination Surveys (NHANES) conducted in 1988–1994 and 2007–2010, were used. The American Thoracic Society/European Respiratory Society (ATS/ERS) criteria were used to define airflow obstruction. Results: Based on ATS/ERS criteria, the overall age-adjusted prevalence of airflow obstruction among adults aged 40–79 years decreased from 16.6% to 14.5% (p < 0.05). Significant decreases were observed for the older age category 60–69 years (20.2% vs. 15.4%; p < 0.01), for males (19.0% vs. 15.4%; p < 0.01), and for Mexican American adults (12.7% vs. 8.4%; p < 0.001). The prevalence of moderate and more severe airflow obstruction decreased also (6.4% vs. 4.4%; p < 0.01). Based on ATS/ERS criteria, during 2007–2010, an estimated 18.3 million U.S. adults 40–79 years had airflow obstruction, 5.6 million had moderate or severe airflow obstruction and 1.4 million had severe airflow obstruction. Conclusions: The overall age-adjusted prevalence of airflow obstruction among U.S. adults aged 40–79 years decreased from 1988–1994 to 2007–2010, especially among older adults, Mexican Americans, and males.

Rebuttal From Drs Pellegrino and Brusasco

There are major reasons for testing acute bronchoreversibility in clinical practice. For instance, finding large increments in FEV1> 400 mL is of great value to confirm the diagnosis of asthma and support therapy. Evaluating whether airflow obstruction is still reversible is also important, even though normal acute responses do not predict effects of chronic treatment and in no case preclude trials with bronchoactive medications. Drs Hansen and Porszasz1 suggest that with respect to the American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines,2 the perceptive threshold is more suitable for evaluating bronchoreversibility.

Spirometric standards and patient characteristics: an exploratory study of factors affecting fulfillment in routine clinical practice.

Spirometry is an apparently simple test, yet the recommended criteria for acceptability and reproducibility can be difficult to fulfill. This study aimed (1) to prospectively assess the number of tests that meet the American Thoracic Society/European Respiratory Society (ATS/ERS) 2005 acceptability and repeatability criteria in the routine practice of an experienced technician at a referral hospital's lung function laboratory, (2) to identify the most common errors, and (3) to explore patient characteristics possibly associated with failure to meet standards. We prospectively evaluated 257 consecutive spirometries supervised by the same technician, who gave priority to achieving a minimum of 3 correct maneuvers within a maximum of 8 attempts. We recorded FVC, FEV1, expiratory time (TE), back-extrapolated volume (VE), end-of-test volume (VEOT), number of maneuvers with and without errors, and errors (VE > 0.15 L or 5% of FVC, TE < 6 s, and VEOT ≥ 0.025 L for ≥ 1 s). Two-hundred and fifteen spirometries (83.7%, 95% CI 78.6-87.7%) met the ATS/ERS 2005 criteria. Acceptability criteria were met in 73.9% (95% CI 71.2-76.3%) of the maneuvers and repeatability criteria in 90.7% (95% CI 86.5-93.6%). A mean ± SD of 3.3 ± 1.4 per subject was acceptable, and a mean ± SD of 4.5 ± 1.9 was obtained. TE and VEOT errors were the most common. Nearly 15% of the subjects failed to fulfill all the ATS/ERS 2005 criteria for spirometry performed even though they were coached by a qualified and regularly trained technician in a hospital lung function laboratory. The fact that the ATS/ERS 2005 criteria cannot be met by all patients in optimal technical conditions should be further considered and explored.

Pulmonary function impairment in patients with chronic heart failure: Lower limit of normal versus conventional cutoff values

ObjectiveTo determine the prevalence of pulmonary function abnormalities in patients with chronic heart failure (HF) according to recent American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines using the lower limit of normal (LLN) compared to conventional cutoff values. BackgroundRecent ATS/ERS guidelines recommend the use of the LLN instead of the conventional cutoff values to define pulmonary function impairment to avoid misclassification of patients. However, studies addressing the prevalence of pulmonary function abnormalities according to both definitions in patients with chronic HF are lacking. MethodsIn this prospective cross-sectional study, 164 chronic HF outpatients (age 68 ± 10 years, 78% men, 88% New York Heart Association class I–II) with left ventricular ejection fraction < 40% underwent spirometry and measurement of diffusing capacity. Body plethysmography was performed in patients with abnormal spirometry results. ResultsDiffusion impairment and airway obstruction were found in 44–58% and 26–37% of the patients, respectively, depending on the definition used (LLN versus conventional cutoff values, p < 0.05). However, restriction was infrequent, irrespective of the definition used (7% versus 5%, respectively, p > 0.05). The LLN identified fewer patients with abnormal lung function, whereas the conventional cutoff values classified more patients with diffusion impairment, airway obstruction, or a mixed category. Twenty-seven percent of patients were misclassified by the conventional cutoff values. ConclusionPulmonary function abnormalities, especially diffusion impairment and airway obstruction, were highly prevalent in patients with chronic HF. Conventional cutoff values classified more patients with diffusion impairment, airway obstruction, or a mixed category compared to the LLN.

The Lower Limit of Normal in the evaluation of pulmonary function

Pulmonary function tests (PFTs) are widely used in the clinical evaluation of patients with pulmonary and cardiovascular disease. The underlying premise is that lung volumes and air flow through the airways are correlated with measurements of body size and are influenced by age. The result is a set of equations that have lung volume and airway flow as dependent variables of height, age, sex, race and weight and their appropriate coefficients as independent predictors. Higher order exponential relationships are accommodated using logarithms. 1 Quanjer P.H. Stanojevic D. Stocks J. Cole C.G. GAMLSS in Action. 2012http://www.lungfunction.org/gamlss.html Google Scholar The assumption that measurements of body size determine lung size and airway flow is derived form basic biological observations that establish that organ size in mammals scales with the square of the length and that measurements of body size determine metabolic rate, heat losses and the mechanical energy necessary for distribution of oxygen through the tissues. 2 Apell S.P. Wahlsten O. Gawlitza H. Body Mass Index – A Physics Perspective. ArXiv e-prints, 2011: 296 Google Scholar , 3 West G.B. Brown J.H. Enquist B.J. A general model for the origin of allometric scaling laws in biology. Science. 1997; 276: 122-126 Crossref PubMed Scopus (3466) Google Scholar , 4 McMahon T. Size and shape in biology. Science. 1973; 179: 1201-1204 Crossref PubMed Scopus (844) Google Scholar Reference equations that establish expected or predicted values for lung volume and for spirometry based on age and height derived from datasets of healthy individuals are widely used. 5 Pulmonary Function Predicted Values. Johns Hopkins Pulmonary Function Laboratory, Baltimore, Maryland, USA2001http://www.hopkinsmedicine.org/pftlab/pfpred.htm Google Scholar , 6 Quanjer P.H. Stocks J. Cole T.J. Hall G.L. Stanojevic S. Influence of secular trends and sample size on reference equations for lung function tests. Eur Respir J. 2011; 37: 658-664 Crossref PubMed Scopus (134) Google Scholar Pulmonary function impairment in patients with chronic heart failure: Lower limit of normal versus conventional cutoff valuesHeart & Lung: The Journal of Cardiopulmonary and Acute CareVol. 43Issue 4PreviewTo determine the prevalence of pulmonary function abnormalities in patients with chronic heart failure (HF) according to recent American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines using the lower limit of normal (LLN) compared to conventional cutoff values. Full-Text PDF

An official American Thoracic Society/European Respiratory Society statement: update on limb muscle dysfunction in chronic obstructive pulmonary disease.

Limb muscle dysfunction is prevalent in chronic obstructive pulmonary disease (COPD) and it has important clinical implications, such as reduced exercise tolerance, quality of life, and even survival. Since the previous American Thoracic Society/European Respiratory Society (ATS/ERS) statement on limb muscle dysfunction, important progress has been made on the characterization of this problem and on our understanding of its pathophysiology and clinical implications. The purpose of this document is to update the 1999 ATS/ERS statement on limb muscle dysfunction in COPD. An interdisciplinary committee of experts from the ATS and ERS Pulmonary Rehabilitation and Clinical Problems assemblies determined that the scope of this document should be limited to limb muscles. Committee members conducted focused reviews of the literature on several topics. A librarian also performed a literature search. An ATS methodologist provided advice to the committee, ensuring that the methodological approach was consistent with ATS standards. We identified important advances in our understanding of the extent and nature of the structural alterations in limb muscles in patients with COPD. Since the last update, landmark studies were published on the mechanisms of development of limb muscle dysfunction in COPD and on the treatment of this condition. We now have a better understanding of the clinical implications of limb muscle dysfunction. Although exercise training is the most potent intervention to address this condition, other therapies, such as neuromuscular electrical stimulation, are emerging. Assessment of limb muscle function can identify patients who are at increased risk of poor clinical outcomes, such as exercise intolerance and premature mortality. Limb muscle dysfunction is a key systemic consequence of COPD. However, there are still important gaps in our knowledge about the mechanisms of development of this problem. Strategies for early detection and specific treatments for this condition are also needed.

Chloral hydrate sedation for infant pulmonary function testing

Chloral hydrate sedation for infant pulmonary function testing