P. H. Quanjer

Bio: P. H. Quanjer is an academic researcher. The author has contributed to research in topics: Lung volumes & European union. The author has an hindex of 20, co-authored 32 publications receiving 9907 citations.

Lung volumes and forced ventilatory flows

Abstract: Lung volumes are subdivided into static and dynamic lung volumes. Static lung volumes are measured by methods which are based on the completeness of respiratory manoeuvres, so that the velocity of the manoeuvres should be adjusted accordingly. The measurements taken during fast breathing movements are described as dynamic lung volumes and as forced inspiratory and expiratory flows. ### 1.1 Static lung volumes and capacities The volume of gas in the lung and intrathoracic airways is determined by the properties of lung parenchyma and surrounding organs and tissues, surface tension, the force exerted by respiratory muscles, by lung reflexes and by the properties of airways. The gas volumes of thorax and lung are the same except in the case of a pneumothorax. If two or more subdivisions of the total lung capacity are taken together, the sum of the constituent volumes is described as a lung capacity. Lung volumes and capacities are described in more detail in § 2. #### 1.1.1 Determinants Factors which determine the size of the normal lung include stature, age, sex, body mass, posture, habitus, ethnic group, reflex factors and daily activity pattern. The level of maximal inspiration (total lung capacity, TLC) is influenced by the force developed by the inspiratory muscles (disorders include e.g. muscular dystrophy), the elastic recoil of the lung (disorders include e.g. pulmonary fibrosis and emphysema) and the elastic properties of the thorax and adjacent structures (disorders include e.g. ankylosis of joints). The level of maximal expiration (residual volume, RV) is determined by the force exerted by respiratory muscles (disorders include e.g. muscle paralysis), obstruction, occlusion and compression of small airways (disorders include e.g. emphysema) and by the mechanical properties of lung and thorax (disorders include diffuse fibrosis, kyphoscoliosis). Assessing the total lung capacity is indispensable in establishing a restrictive ventilatory defect or in diagnosing abnormal lung distensibility, as may occur in patients …

Airway Responsiveness. Standardized Challenge Testing With Pharmacological, Physical and Sensitizing Stimuli in Adults. Report Working Party Standardization of Lung Function Tests, European Community for Steel and Coal. Official Statement of the European Respiratory Society

Abstract: Asthma and chronic obstructive pulmonary disease (COPD, also called chronic airflow limitation (CAL)) are the most frequent diagnoses in patients with intrathoracic airways obstruction [1]. Often these patients show a spontaneous variability in the degree of airways obstruction, which can be documented by serial lung function measurements. Large variability in the degree of airways obstruction is indicative of an increased susceptibility of the patient to environmental stimuli that cause acute airway narrowing. Knowledge of the potential severity of these episodes of acute airways obstruction is of clinical interest. Therefore, several quantitative measures of the response of the airways to bronchoconstrictors in vivo have been advocated over the past two decades. The objective of the present guidelines is to address the methodological issues of the various available techniques, and to provide up-to-date international guidelines on standardization. The present recommendations might not represent the potentially best methodologies. However, they do represent the currently validated techniques, by which interchangeable results can be obtained among laboratories. Variable airways obstruction can be mimicked in the laboratory by challenge tests with bronchoconstrictive stimuli (fig. 1) [2]. This enables one to measure the degree of the so-called «airway responsiveness» of the subject to a particular agent. Since the bronchoconstrictive response varies from one stimulus to another, one needs to specify the challenging agent. Therefore, the term «nonspecific» airway responsiveness should be abandoned. Figure 1– Dose-response curves to inhaled methacholine using the dosimeter method in 3 subjects. Airway hyperresponsiveness in asthma is characterised by a leftward shift of the curve (hypersensitivity), a steeper slope (hyperreactivity), and an increase in maximal response (excessive airway narrowing). Modified from de Pee et al. [243] with permission. Airway hyperresponsiveness refers to an exaggerated response to the bronchoconstrictor. This is reflected by an increased sensitivity to the stimulus, which …

Standardization of the measurement of transfer factor (diffusing capacity)

Abstract: ### 1.1 What is being measured The lung is the organ of external respiration for the exchange of oxygen and carbon dioxide between the blood and the surrounding air. The stages in the process of gas transfer include: 1. Ventilation of the airways and some air spaces by bulk flow of gas; 2. Mixing and diffusion of gases in the alveolar ducts, air sacs and alveoli; 3. Transfer of gases across the gaseous to liquid interface of the alveolar membrane; 4. Mixing and diffusion in the lung parenchyma and alveolar capillary plasma; 5. Chemical reaction with constituents of blood; 6. Circulation of blood between the pulmonary and systemic vascular beds. The capacity of the lung to exchange gas is determined by the structural and functional dimensions of these processes. The structural dimensions include the lung volume, the path length for diffusion in the gas phase, the thickness and area of the alveolar capillary membrane including any effects of airway closure, and the volume of blood in capillaries supplying alveoli which are ventilated. The principal functional dimensions are the absolute levels of ventilation and perfusion and the uniformity of their distribution with respect to both each other and the diffusion characteristics of the membrane. Other functional dimensions are the quantity of haemoglobin in the alveolar capillaries, the composition of the alveolar gas, the gas tensions in blood entering the alveolar capillaries, the rates of chemical reaction with haemoglobin and of dissociation of the compound so formed, the transit time of blood through that part of the pulmonary vascular bed which exchanges gas with the alveoli and the slope of the relevant haemoglobin dissociation curve. The latter is a function of the temperature of the lung and the prevailing levels of oxygen, carbon dioxide, hydrogen ions and 2,3-diphosphoglycerate; many of these variables are dependent on the level of …

Reference values for residual volume, functional residual capacity and total lung capacity. ATS Workshop on Lung Volume Measurements. Official Statement of The European Respiratory Society.

Abstract: Reference values play an important role in establishing whether, in an individual, measured volumes fall within a range to be expected for a healthy person of the same sex, similar stature, age, and other characteristics. Hence, reference values should be chosen that are appropriate to the person being investigated. Ideally, the reference values should be consistent; in the context of this paper, it implies that predictions for the various lung volumes have been derived from the same reference population, with the same techniques. Comparing measured with reference values is fraught with difficulties, as it may lead to disease going undetected. This is because the scatter in predicted values is sufficiently large to allow a sick person to lose, e.g. much of his total lung capacity (TLC), whilst still remaining in the range observed in comparable healthy persons. In addition, measurements in an "abnormal range" are not diagnostic of a specific disease, as many diagnostic entities may cause static lung volumes to be abnormal. Hence, in the follow-up of a patient, reliance should be placed much more on the effects of drugs or challenges with pharmacological, chemical or physical stimuli or allergens, and on the rate of change of lung volumes, than on the relationship of an isolated result to published "normative data". In fact, the best reference value is the value observed in a period when the disease is stable and minimal for that person. In studies such as the effects of drugs in patients with lung disease, or of adverse effects of environmental factors on the lungs, observed values should not be compared with reference values; instead, a comparison should be made with values obtained in an appropriately chosen control group.

Standardisation of spirometry

Abstract: [⇓][1] SERIES “ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING” Edited by V. Brusasco, R. Crapo and G. Viegi Number 2 in this Series [1]: #F13

Interpretative strategies for lung function tests

Abstract: SERIES “ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING” Edited by V. Brusasco, R. Crapo and G. Viegi Number 5 in this Series This section is written to provide guidance in interpreting pulmonary function tests (PFTs) to medical directors of hospital-based laboratories that perform PFTs, and physicians who are responsible for interpreting the results of PFTs most commonly ordered for clinical purposes. Specifically, this section addresses the interpretation of spirometry, bronchodilator response, carbon monoxide diffusing capacity ( D L,CO) and lung volumes. The sources of variation in lung function testing and technical aspects of spirometry, lung volume measurements and D L,CO measurement have been considered in other documents published in this series of Task Force reports 1–4 and in the American Thoracic Society (ATS) interpretative strategies document 5. An interpretation begins with a review and comment on test quality. Tests that are less than optimal may still contain useful information, but interpreters should identify the problems and the direction and magnitude of the potential errors. Omitting the quality review and relying only on numerical results for clinical decision making is a common mistake, which is more easily made by those who are dependent upon computer interpretations. Once quality has been assured, the next steps involve a series of comparisons 6 that include comparisons of test results with reference values based on healthy subjects 5, comparisons with known disease or abnormal physiological patterns ( i.e. obstruction and restriction), and comparisons with self, a rather formal term for evaluating change in an individual patient. A final step in the lung function report is to answer the clinical question that prompted the test. Poor choices made during these preparatory steps increase the risk of misclassification, i.e. a falsely negative or falsely positive interpretation for a lung function abnormality or a change …

Multi-ethnic reference values for spirometry for the 3–95-yr age range: the global lung function 2012 equations

Abstract: The aim of the Task Force was to derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Over 160,000 data points from 72 centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5-95 yrs. Lung function data were collated and prediction equations derived using the LMS method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals aged 3-95 yrs for Caucasians (n=57,395), African-Americans (n=3,545), and North (n=4,992) and South East Asians (n=8,255). Forced expiratory value in 1 s (FEV(1)) and forced vital capacity (FVC) between ethnic groups differed proportionally from that in Caucasians, such that FEV(1)/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Spirometric prediction equations for the 3-95-age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent and Arabic, Polynesian and Latin American countries, as well as Africa will further improve these equations in the future.

Allergic Rhinitis and Its Impact on Asthma

Abstract: Authors Jan L. Brozek, MD, PhD – Department of Clinical Epidemiology & Biostatistics and Medicine, McMaster University, Hamilton, Canada Jean Bousquet, MD, PhD – Service des Maladies Respiratoires, Hopital Arnaud de Villeneuve, Montpellier, France, INSERM, CESP U1018, Respiratory and Environmental Epidemiology Team, France, and WHO Collaborating Center for Rhinitis and Asthma Carlos E. Baena-Cagnani, MD – Faculty of Medicine, Catholic University of Cordoba, Cordoba, Argentina Sergio Bonini, MD – Institute of Neurobiology and Molecular Medicine – CNR, Rome, Italy and Department of Medicine, Second University of Naples, Naples, Italy G. Walter Canonica, MD – Allergy & Respiratory Diseases, DIMI, Department of Internal Medicine, University of Genoa, Genoa, Italy Thomas B. Casale, MD – Division of Allergy and Immunology, Department of Medicine, Creighton University, Omaha, Nebraska, USA Roy Gerth van Wijk, MD, PhD – Section of Allergology, Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, the Netherlands Ken Ohta, MD, PhD – Division of Respiratory Medicine and Allergology, Department of Medicine, Teikyo University School of Medicine, Tokyo, Japan Torsten Zuberbier, MD – Department of Dermatology and Allergy, Charite Universitatsmedizin Berlin, Berlin, Germany Holger J. Schunemann, MD, PhD, MSc – Department of Clinical Epidemiology & Biostatistics and Medicine, McMaster University, Hamilton, Canada