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Richard Kraemer,1,2 Hans-Jürgen Smith,3 Fabian Gardin,4 Jürg Barandun,4 Stefan Minder,3 Lukas Kern,5 Martin H Brutsche5 1Center of Pulmonary Medicine, Hirslanden Private Hospital Group, Salem-Hospital, Bern, Switzerland; 2Department of Biomedical Research, University of Bern, Bern, Switzerland; 3Medical Development, Research in Respiratory Diagnostics, Berlin, Germany; 4Center of Pulmonary Medicine, Hirslanden Private Hospital Group, Clinic Hirslanden, Zürich, Switzerland; 5Clinic of Pneumology, Cantonal Hospital St. Gallen, St. Gallen, SwitzerlandCorrespondence: Richard KraemerCenter of Pulmonary Medicine, Hirslanden Private Hospital Group, Schänzlistrasse 39, Berne, CH-3013, SwitzerlandTel +41 79 300 26 53Email richard.kraemer@hirslanden.chBackground: Airflow reversibility criteria in COPD are still debated – especially in situations of co-existing COPD and asthma. Bronchodilator response (BDR) is usually assessed by spirometric parameters. Changes assessed by plethysmographic parameters such as the effective, specific airway conductance (sGeff), and changes in end-expiratory resting level at functional residual capacity (FRCpleth) are rarely appreciated. We aimed to assess BDR by spirometric and concomitantly measured plethysmographic parameters. Moreover, BDR on the specific aerodynamic work of breathing (sWOB) was evaluated.Methods: From databases of 3 pulmonary centers, BDR to 200 g salbutamol was retrospectively evaluated by spirometric (∆FEV1 and ∆FEF25– 75), and plethysmographic (∆sGeff, ∆FRCpleth, and ∆sWOB) parameters in a total of 843 patients diagnosed as COPD (478 = 57%), asthma-COPD-overlap (ACO) (139 = 17%), or asthma (226 = 27%), encountering 1686 BDR-measurement-sets (COPD n = 958; ACO n = 276; asthma n = 452).Results: Evaluating z-score improvement taking into consideration the whole pre-test z-score range, highest BDR was achieved by combining ∆sGeff and ∆FRC detecting BDR in 62.2% (asthma: 71.4%; ACO: 56.7%; COPD: 59.8%), by ∆sGeff in 53.4% (asthma: 69.1%; ACO: 51.6%; COPD: 47.4%), whereas ∆FEV1 only distinguished in 10.6% (asthma: 21.8%; ACO: 18.6%; COPD: 4.2%). Remarkably, ∆sWOB detected BDR in 49.4% (asthma: 76.2%; ACO: 47.8%; COPD: 46.9%).Conclusion: BDR largely depends on the pre-test functional severity and, therefore, should be evaluated in relation to the pre-test conditions expressed as ∆z-scores, considering changes in airway dynamics, changes in static lung volumes and changes in small airway function. Plethysmographic parameters demonstrated BDR at a significant higher rate than spirometric parameters.Keywords: COPD, bronchodilator response, COPD and coexisting asthma, ACO, pulmonary hyperinflation, small airways dysfunction, aerodynamic work of breathing

In patients with moderate-to-severe Chronic Obstructive Pulmonary Disorder (COPD), pulmonary hyperinflation can occur at rest and increase during episodes of exacerbation. Among other mechanical constraints, changes in position and configuration of the diaphragm are also induced by increased end-expiratory lung volume. Both descent and flattening of diaphragm might damage the phrenic nerves by stretching their fibers. The study aimed to investigate the phrenic nerve conduction in COPD patients in stable conditions and during COPD exacerbation. In a group of 11 COPD patients without relevant comorbidities in stable conditions and subsequently in another group of 10 COPD patients during in-hospital COPD exacerbation and recovery, measurements of functional respiratory parameters and assessment of phrenic nerves motor conduction by bilateral electric stimulation were performed concurrently. Significant increase in phrenic nerves latency (

In patients with obstructive pulmonary disease, airway narrowing can induce ventilatory disturbances such as expiratory flow limitation (EFL) and/or pulmonary hyperinflation (PH). In such a context, the metabolic balance could be disturbed within the intercostal muscle tissue, especially during exercise, which could promote the onset or worsening of dyspnea.To simulate ventilatory disturbances that may be encountered by patients with obstructive pulmonary diseases (e.g. abnormally high resistance of the airways to expiration, EFL and PH), a positive expiratory pressure (PEP) of 20 cmH2O was imposed at rest and during exercise in healthy subjects. Oxygenation of the intercostal muscles was measured by near-infrared spectroscopy at the 7th intercostal space.At rest, a decrease in oxyhemoglobin concentration ([O2Hb]) probably linked to a decrease in total hemoglobin concentration ([tHb], i.e. local blood volume) was observed in response to PEP (Study 1). However, no reduction in tissue oxygen saturation index (TSI) was reported (Studies 1 to 3), even in a context of PEP-induced PH (Study 2). During exercise, a lower increase in [O2Hb] and [tHb] was observed when PEP was imposed (vs. control). A decrease in TSI and inspiratory capacity was also reported between rest and exercise in this condition (Study 3).According to the results of our studies, when a PEP of 20 cmH2O is imposed at rest in young healthy subjects, no metabolic imbalance seems to occur in the intercostal muscles. However, when this PEP is imposed during exercise, a disturbance of the metabolic balance seems to happen. This could be partly explained by local hemodynamic alterations induced by PH. However, further studies are needed to clarify this aspect.Finally, no relationship between dyspnea and the metabolic condition of the intercostal muscles was observed during our studies. However, correlations between respiratory discomfort and instantaneous ventilatory flows were highlighted at rest and during exercise with PEP (Studies 1 and 3). A relationship between dyspnea and PH was also observed at rest (Study 2).Future research will aim to verify, at rest and during exercise, whether the oxygenation of the intercostal muscles is influenced by PH in patients with obstructive pulmonary pathologies.; Chez les patients atteints de pathologies pulmonaires obstructives, le rétrécissement du calibre des bronches peut induire des perturbations fonctionnelles ventilatoires comme la limitation de débit expiratoire (LDE) et/ou l’hyperinflation pulmonaire (HP). Dans un tel contexte, l’équilibre métabolique pourrait être perturbé au sein du tissu musculaire intercostal, notamment à l’exercice, ce qui pourrait favoriser la survenue ou l’aggravation de la dyspnée.Pour simuler les perturbations ventilatoires que peuvent rencontrer les patients atteints de pathologies pulmonaires obstructives (e.g. résistance anormalement élevée des voies aériennes à l’expiration, LDE et HP), une pression expiratoire positive (PEP) de 20 cmH2O a été imposée au repos et à l’exercice chez des sujets sains. L’oxygénation des muscles intercostaux a été mesurée par spectroscopie dans le proche infrarouge au niveau du 7ème espace intercostal.Au repos, une diminution de la concentration en oxyhémoglobine ([O2Hb]) probablement liée à une baisse de la concentration en hémoglobine totale ([tHb], i.e. volume sanguin local) a été observée en réponse à la PEP (Étude 1). Toutefois, aucune diminution de l’indice de saturation tissulaire en oxygène (TSI) n’a été constatée (Études 1 à 3), y compris lorsque la PEP était à l’origine d’une HP (Étude 2). A l’exercice, une moindre augmentation de [O2Hb] et de [tHb] a été rapportée lorsque la PEP était imposée (vs. contrôle). Une diminution du TSI et de la capacité inspiratoire a aussi été observée entre le repos et l’exercice dans cette condition (Étude 3).D’après les résultats de nos études, lorsqu’une PEP de 20 cmH2O est imposée au repos chez de jeunes sujets sains, aucun déséquilibre métabolique ne semble se produire au niveau des muscles intercostaux. En revanche, lorsque cette PEP est imposée à l’exercice, une perturbation de l’équilibre métabolique semble avoir lieu. Cette dernière pourrait être en partie expliquée par des altérations hémodynamiques locales induites par l’HP. Toutefois, des études complémentaires sont nécessaires pour éclaircir cet aspect.Enfin, aucune relation entre la dyspnée et la condition métabolique des muscles intercostaux n’a été observée lors de nos études. En revanche, des corrélations entre l’inconfort respiratoire et les débits ventilatoires instantanés ont été mises en évidence au repos et à l’exercice lorsque la PEP était imposée (Études 1 et 3). Une relation entre la dyspnée et l’HP a aussi été observée au repos (Étude 2).Les travaux de recherche futurs auront pour objectif de vérifier, au repos et à l’exercice, si l’oxygénation des muscles intercostaux est influencée par l’HP chez des patients atteints de pathologies pulmonaires obstructives.

In patients with obstructive pulmonary disease, airway narrowing can induce ventilatory disturbances such as expiratory flow limitation (EFL) and/or pulmonary hyperinflation (PH). In such a context, the metabolic balance could be disturbed within the intercostal muscle tissue, especially during exercise, which could promote the onset or worsening of dyspnea.To simulate ventilatory disturbances that may be encountered by patients with obstructive pulmonary diseases (e.g. abnormally high resistance of the airways to expiration, EFL and PH), a positive expiratory pressure (PEP) of 20 cmH2O was imposed at rest and during exercise in healthy subjects. Oxygenation of the intercostal muscles was measured by near-infrared spectroscopy at the 7th intercostal space.At rest, a decrease in oxyhemoglobin concentration ([O2Hb]) probably linked to a decrease in total hemoglobin concentration ([tHb], i.e. local blood volume) was observed in response to PEP (Study 1). However, no reduction in tissue oxygen saturation index (TSI) was reported (Studies 1 to 3), even in a context of PEP-induced PH (Study 2). During exercise, a lower increase in [O2Hb] and [tHb] was observed when PEP was imposed (vs. control). A decrease in TSI and inspiratory capacity was also reported between rest and exercise in this condition (Study 3).According to the results of our studies, when a PEP of 20 cmH2O is imposed at rest in young healthy subjects, no metabolic imbalance seems to occur in the intercostal muscles. However, when this PEP is imposed during exercise, a disturbance of the metabolic balance seems to happen. This could be partly explained by local hemodynamic alterations induced by PH. However, further studies are needed to clarify this aspect.Finally, no relationship between dyspnea and the metabolic condition of the intercostal muscles was observed during our studies. However, correlations between respiratory discomfort and instantaneous ventilatory flows were highlighted at rest and during exercise with PEP (Studies 1 and 3). A relationship between dyspnea and PH was also observed at rest (Study 2).Future research will aim to verify, at rest and during exercise, whether the oxygenation of the intercostal muscles is influenced by PH in patients with obstructive pulmonary pathologies., Chez les patients atteints de pathologies pulmonaires obstructives, le rétrécissement du calibre des bronches peut induire des perturbations fonctionnelles ventilatoires comme la limitation de débit expiratoire (LDE) et/ou l’hyperinflation pulmonaire (HP). Dans un tel contexte, l’équilibre métabolique pourrait être perturbé au sein du tissu musculaire intercostal, notamment à l’exercice, ce qui pourrait favoriser la survenue ou l’aggravation de la dyspnée.Pour simuler les perturbations ventilatoires que peuvent rencontrer les patients atteints de pathologies pulmonaires obstructives (e.g. résistance anormalement élevée des voies aériennes à l’expiration, LDE et HP), une pression expiratoire positive (PEP) de 20 cmH2O a été imposée au repos et à l’exercice chez des sujets sains. L’oxygénation des muscles intercostaux a été mesurée par spectroscopie dans le proche infrarouge au niveau du 7ème espace intercostal.Au repos, une diminution de la concentration en oxyhémoglobine ([O2Hb]) probablement liée à une baisse de la concentration en hémoglobine totale ([tHb], i.e. volume sanguin local) a été observée en réponse à la PEP (Étude 1). Toutefois, aucune diminution de l’indice de saturation tissulaire en oxygène (TSI) n’a été constatée (Études 1 à 3), y compris lorsque la PEP était à l’origine d’une HP (Étude 2). A l’exercice, une moindre augmentation de [O2Hb] et de [tHb] a été rapportée lorsque la PEP était imposée (vs. contrôle). Une diminution du TSI et de la capacité inspiratoire a aussi été observée entre le repos et l’exercice dans cette condition (Étude 3).D’après les résultats de nos études, lorsqu’une PEP de 20 cmH2O est imposée au repos chez de jeunes sujets sains, aucun déséquilibre métabolique ne semble se produire au niveau des muscles intercostaux. En revanche, lorsque cette PEP est imposée à l’exercice, une perturbation de l’équilibre métabolique semble avoir lieu. Cette dernière pourrait être en partie expliquée par des altérations hémodynamiques locales induites par l’HP. Toutefois, des études complémentaires sont nécessaires pour éclaircir cet aspect.Enfin, aucune relation entre la dyspnée et la condition métabolique des muscles intercostaux n’a été observée lors de nos études. En revanche, des corrélations entre l’inconfort respiratoire et les débits ventilatoires instantanés ont été mises en évidence au repos et à l’exercice lorsque la PEP était imposée (Études 1 et 3). Une relation entre la dyspnée et l’HP a aussi été observée au repos (Étude 2).Les travaux de recherche futurs auront pour objectif de vérifier, au repos et à l’exercice, si l’oxygénation des muscles intercostaux est influencée par l’HP chez des patients atteints de pathologies pulmonaires obstructives.

The paper aimed to present evidence of the effect of some pathophysiological features of chronic obstructive pulmonary disease (COPD) on cardiac remodeling in patients free of overt cardiovascular diseases, traditional cardiovascular risk factors and pulmonary hypertension. Contrary to traditional beliefs that cardiac abnormalities in COPD have been mainly associated with the right ventricle, several recent studies have shown an independent effect of pulmonary hyperinflation and emphysema on left ventricular (LV) diastolic filling and LV hypertrophy. Pulmonary hyperinflation and emphysema cause intrathoracic hypovolemia, low preload, small end-diastolic dimension and mechanical compression of LV chamber which could worsen end-diastolic stiffness. Interestingly, that the presence of LV hypertrophy in COPD patients is important but currently poorly understood area of investigation. Pulmonary hyperinflation, increased arterial stiffness and sympathetic activation may be associated with LV hypertrophy. Two-dimensional ultrasound speckle tracking studies have shown the presence of sub-clinical LV systolic dysfunction in patients even with moderate COPD and free of overt cardiovascular diseases. Sarcopenia related to the inflammatory-catabolic state in COPD and hypoxia could play an important role regarding LV systolic dysfunction. Recent data reported the effects of long-acting bronchodilators on reducing lung hyperinflation (inducing lung deflation). Further studies are required to evaluate the effects of pharmacological lung deflation therapy on cardiac volume and function.

Aim. To evaluate the structural and functional changes in the lungs of ST elevation myocardial infarction (STEMI) patients with absence or presence of chronic obstructive lung disease (COPD), and the relation with myocardial dysfunction and systemic inflammation.Material and methods. Totally, 189 STEMI patients included: group 1 — STEMI with COPD of moderate and mild grade, 2 — STEMI with no lung pathology. Groups were comparable by clinical and anamnestic parameters. Assessment of lung function and blood collection were done at 10­12 day of STEMI. For comparison of the parameters representing structural and functional changes in the lungs and comparison of C­reactive protein (CRP), N­terminal pro­brain natriuretic peptide (NT­proBNP) concentration, a control group was formed with no pulmonary pathology, comparable by age and sex with the STEMI patients.Results. In COPD patients, higher values revealed of the parameters representing the part of residual volumes in pulmonary structure. Higher residual volume (RV) was found also in STEMI and no COPD comparing to controls, however the relation RV/TLC (total lung capacity) was not higher than normal range. In both groups there were lower values of diffusion lung capacity (DLCO) comparing to controls. The lowest DLCO found in COPD patients. Concentration of NT­proBNP (H=41,6; pConclusion. In STEMI patients the increase revealed of residual lung volumes. Mostly the level of residual volumes is high in STEMI and COPD patients. There are associations of NT­proBNP and CRP with structural and functional parameters of the lungs regardless of COPD.

Introduction: Vital capacity (VC) can be determined through expiratory (EVC) or inspiratory maneuvers (IVC). It is fundamental for determination of lung volumes and its incomplete mobilization has repercussions on the detection of air trapping or pulmonary hyperinflation. VC is also essential for detection of airway obstruction through the FEV1/VC ratio. Aims: To determine the differences between EVC and IVC (EVC-IVC) according to ventilatory pattern; to characterize the FEV1/EVC and FEV1/IVC ratios; to study the effects of EVC or IVC on the detection of air trapping or pulmonary hyperinflation. Methods: The sample included 388 subjects of both genders. In half of the sample the VC was determined first by the EVC and then by the IVC and in the other half in the reverse order. The sample was divided into 3 groups: without ventilatory changes (normal), airway obstruction and pulmonary restriction. Results: The EVC-IVC parameter was greater than 200 mL in 34.8% of the normal group, 28.4% of the airway obstruction group and 22.4% of the pulmonary restriction group. The ratio FEV1/EVC Conclusions: The EVC and IVC maneuvers shouldn’t be considered interchangeable due to differences in the volume obtained for each of them. These differences consequently influence the interpretation of lung function results.

Progressive airflow limitation is a principal sign of chronic obstructive pulmonary disease (COPD) which leads to pulmonary hyperinflation, progressive exertional breathlessness, reducing physical activity in daily life, deconditioning and significant decrease in quality of life. This phenomenon is noted in early stage of COPD. The earliest disruption of this 'vicious circle' is thought to result in better clinical outcome. Current combined bronchodilator therapy, such as a fixed combination of tiotropium/olodaterol, can significantly improve clinical status, dyspnea, physical limitation, deconditioning and quality of life of the patients due to improvement in bronchial obstruction and pulmonary hyperinflation. Therefore, the most promising approach today and in the nearest future is to start the optimal combined dual bronchodilator therapy at earlier stage of the disease.

This randomized controlled trial study aimed to identify the optimal positive pressure (PP) level that can clear atelectasis while avoiding pulmonary hyperinflation during the breath-hold technique in dogs undergoing thoracic computed tomography (CT). Sixty dogs affected by mammary tumors undergoing thoracic CT for the screening of pulmonary metastases were randomly assigned to six groups with different levels of PP during the breath-hold technique: 0 (control), 5 (PP5), 8 (PP8), 10 (PP10), 12 (PP12), and 15 (PP15) cmH2 O. The percentage of atelectatic lung region was lower in the PP10 (3.7 ± 1.1%; P = 0.002), PP12 (3.4 ± 1.3%; P = 0.0001), and PP15 (2.8 ± 0.9%; P = 0.006) groups than in the control group (5.0 ± 2.3%), and the percentage of poorly aerated lung region was lower in the PP8 (15.1 ± 2.6%; P = 0.0009), PP10 (13.0 ± 2.0 %; P = 0.002), PP12 (13.0 ± 2.2 %; P = 0.0002), and PP15 (11.1 ± 1.9%; P = 0.0002) groups than in the control group (19.8 ± 5.0). The percentage of normally aerated lung region, however, was higher in the PP10 (79.7 ± 4.1%; P = 0.005), PP12 (79.8 ± 5.1%; P = 0.0002), and PP15 (80.2 ± 4.9%; P = 0.002) groups than in the control group (73.4 ± 6.6%). A PP of 10-12 cmH2 O during the breath-hold technique should be considered to improve lung aeration during a breath-hold technique in dogs undergoing thoracic CT.

Introdução: A reabilitação pulmonar (RP) e a redução de volume pulmonar por válvula endobrônquica (RVPVE) são intervenções destinadas a melhorar os sintomas, a capacidade funcional e a qualidade de vida na doença pulmonar obstrutiva crônica (DPOC). No entanto, pouco se sabe sobre os efeitos da RP combinada com a RVPVE na hiperinsuflação dinâmica (HD) na DPOC. Objetivos: Avaliar os efeitos da RP associada à RVPVE na hiperinsuflação dinâmica, tolerância ao exercício, desfechos funcionais e qualidade de vida em pacientes com DPOC. Métodos: Foram avaliados 16 pacientes portadores de DPOC (Gold III e IV) divididos em grupo com válvula endobrônquica (submetidos à RVPVE) e controle (sem RVPVE) pré e pós-RP. A RP consistiu de 20 sessões de treinamento combinado (treinamento intervalado em cicloergômetro e de força muscular). Para o estudo da HD, a capacidade inspiratória (CI) foi medida durante os testes submáximo no cicloergômetro e hiperventilatório em repouso. Limite de tempo (Tlim) no teste submáximo, distância no teste de caminhada de seis minutos (TC6), dispneia (escala modificada Medical Research Council, escala mMRC), índice BODE (Body mass index, airway Obstruction, Dyspnea, and Exercise capacity), teste de avaliação da DPOC (CAT) e qualidade de vida (questionário respiratório de Saint George, SGRQ) foram medidos antes e depois da RP. Os testes t de Student não pareado e Generalized Estimating Equations (GEE) foram usados para analisar os principais efeitos da RP e as interações grupo, tempo e grupo* tempo (α = 0,05). Resultados: O grupo com válvulas apresentou um nível final de HD 0,12 litros menor que o grupo controle no teste submáximo após RP (p > 0,05). Interações significativas foram encontradas na HD durante o teste submáximo (ΔCI isotime: -17,8% grupo válvula, +24% grupo controle; ΔCI final: -20% grupo válvula, +34,5% grupo controle) após PR. No teste hiperventilatório em repouso, não foram encontradas diferenças na HD entre os grupos ou momentos do teste (p>0,05). Na amostra total, a RP aumentou o Tlim (3 vezes), a distância no TC6 (+17%), diminuiu a dispneia (mMRC: -60%), o índice BODE (-33,3%) e o CAT (-22,2%) e aumentou a qualidade de vida (-26,2%) (p < 0,05 para todos). Conclusões: Observou-se interação significativa entre redução da HD no grupo válvula e aumento da HD no grupo controle após PR. Entretanto, a RP isoladamente ou combinada com a RVPVE não melhorou significativamente a HD. A RP melhorou o desempenho no exercício, os sintomas, o índice BODE e a qualidade de vida em pacientes com DPOC. Introduction: Pulmonary rehabilitation (PR) and bronchoscopic lung volume reduction (BLVR) are interventions designed to improve symptoms, functional capacity and quality of life in chronic obstructive pulmonary disease (COPD). However, little is known about the effects of PR combined with BLVR on dynamic hyperinflation (DH) in COPD. Aims: To evaluate the effects of PR associated with BLVR on dynamic hyperinflation, exercise tolerance, functional outcomes and quality of life in COPD patients. Methods: Sixteen COPD patients (Gold III and IV) divided into valve (submitted to BLVR) and control groups (without BLVR) were evaluated pre and post PR. PR consisted of 20 sessions of combined training (interval training on a cycle ergometer and muscle strength). To study DH, inspiratory capacity (IC) was measured during the constant work rate test (CWRT) and resting hyperventilatory test. Time limit (Tlim), the six minute walking test (6MWT) distance, dyspnea (modified Medical Research Council scale, mMRC scale), the body mass index, airway obstruction, dyspnea, and exercise capacity index (BODE index), COPD Assessment Test (CAT) and quality of life (Saint George´s respiratory questionnaire (SGRQ) were measured before and after PR. To compare the baseline variables of the two groups, Student's unpaired t-test was used. GEE was performed to analyze the main effects of PR on group, time and group*time interactions (α = 0.05). Results: The valve group presented an end DH 0.12 liters lower than the control group at CWRT after PR (p > 0.05). Significant interactions were found at DH during CWRT (isotime ΔIC: -17.8% valve group, +24% control group; end ΔIC: -20% valve group, +34.5% control group) after PR. In the resting hyperventilatory test, no differences in DH were found between groups or test time (p > 0.05). In the total sample, the PR increased Tlim (3 times), 6MWT distance (+17%), decreased dyspnea (mMRC: -60%), the BODE index (-33.3%) and CAT (-22.2%) and increased quality of life (-26.2%) (p < 0.05 for all). Conclusions: A significant interaction between reduced DH in the valve group and increased DH in the control group after PR was observed. However, PR alone or combined with BLVR did not significantly improve DH. PR enhanced exercise performance, symptoms, BODE index and quality of life in COPD patients.

The objective of the research was to determine the characteristics of arterial stiffness and cardiovascular risk in patients with co-existence of asthma and chronic obstructive pulmonary disease.Materials and methods. The study included patients with symptoms of chronic obstructive pulmonary disease, those with asthma and chronic obstructive pulmonary disease and the group of apparently healthy individuals.Results. In patients with obstructive lung disease, the parameters of vascular stiffness and central blood pressure reflecting the degree of cardiovascular risk were significantly higher as compared to those in apparently healthy individuals. They were significantly elevated in patients with chronic obstructive pulmonary disease and asthma-chronic obstructive pulmonary disease overlap. The indicators of central blood pressure were significantly higher in patients with asthma-chronic obstructive pulmonary disease overlap and more pronounced bronchial obstruction, and in patients with more obvious symptoms of obstructive pathology. Excess body weight or obesity had a strong and pronounced effect on the parameters of central blood pressure in patients with asthma-chronic obstructive pulmonary disease overlap. In patients with a comorbidity, a reliable correlation between the indicator of the presence of pulmonary hyperinflation and the degree of arterial stiffness was revealed.

Pulmonary hyperinflation attained by glossopharyngeal insufflation (GPI) challenges the circulation by compressing the heart and pulmonary vasculature. Our aim was to determine the amount of blood translocated from the central blood volume during GPI. Cardiac output and cardiac chamber volumes were assessed by magnetic resonance imaging in twelve breath- hold divers at rest and during apnea with GPI. Pulmonary blood volume was determined from pulmonary blood flow and transit times for gadolinium during first-pass perfusion after intravenous injection. During GPI, the lung volume increased by 0.8 ± 0.6 L (11 ± 7%) above the total lung capacity. All cardiac chambers decreased in volume and despite a heart rate increase of 24 ± 29 bpm (39 ± 50%), pulmonary blood flow decreased by 2783 ± 1820 mL (43 ± 20%). The pulmonary transit time remained unchanged at 7.5 ± 2.2 s and pulmonary blood volume decreased by 354 ± 176 mL (47 ± 15%). In total, central blood volume decreased by 532 ± 248 mL (46 ± 14%). Voluntary pulmonary hyperinflation leads to ∼50% decrease in pulmonary and central blood volume.

Spirometry is the principal method of diagnosis and evaluation of severity and therapeutic efficacy in patients with chronic obstructive pulmonary disease (COPD). According to the current definition of this disease the main pathophysiological sign of COPD is persistent and generally progres sive airflow limitation. This article will reviews common spirometric parameters used for COPD diagnosis and a diagnostic value of FEV1 / FVC ratio used in absolute values or as the lower limit of its normal range. Spirometry allows detecting pulmonary hyperinflation, particularly using the inspiratory capacity; this possibility is very important but is not widely applied. This is a probable reason of COPD underestimation and late diagnosis. Underestimation of COPD is thought to be due to low spirometry implementation in primary care practice as majority of COPD patients seek medical care in the advanced disease when pulmonary function has already been lost significantly. A great problem for wide implementation of spirometry in general practice is difficulty to learn adequate spirometric testing and interpretation of test results. Notwithstanding a new integral assessment of COPD underlying the current COPD classification spirometric parameters (FEV1 < 50 %pred.) often are the leading criteria to predict a high risk of future exacerbations. Recent data have been demonstrated that early spirometric diagnosis of COPD in primary care is the most effective strategy providing more sufficient therapy results.

Purpose Trained breath-hold divers hyperinflate their lungs by glossopharyngeal insufflation (GPI) to prolong submersion time and withstand lung collapse at depths. Pulmonary hyperinflation leads to profound hemodynamic changes. Methods Thirteen divers performed preparatory breath- holds followed by apnea with GPI. Filling of extrathoracic veins was determined by ultrasound and magnetic resonance imaging and peripheral extravasation of fluid was assessed by electrical impedance. Femoral vein diameter was measured by ultrasound throughout the easy- going and struggle phase of apnea with GPI in eight divers in a sub-study. Results After GPI, pulmonary volume increased by 0.8 ± 0.6 L above total lung capacity. The diameter of the superior caval (by 36 ± 17%) and intrathoracic part of the inferior caval vein decreased (by 21 ± 16%), while the diameters of the internal jugular (by 53 ± 34%), hepatic (by 28 ± 40%), abdominal part of the inferior caval (by 28 ± 28%), and femoral veins (by 65 ± 50%) all increased (P < 0.05). Blood volume of the internal jugular, the hepatic, the abdominal part of the inferior caval vein, and the combined common iliac and femoral veins increased by 145 ± 115, 80 ± 88, 61 ± 60, and 183 ± 197%, respectively. In the sub-study, femoral vein diameter increased by 44 ± 33% in the easy-going phase of apnea with GPI, subsequently decreasing by 20 ± 16% during the struggle phase. Electrical impedance remained unchanged over the thigh and forearm, thus excluding peripheral fluid extravasation. Conclusions GPI leads to heart and pulmonary vessel compression, resulting in redistribution of blood to extrathoracic capacitance veins proximal to venous valves. This is partially reversed by the onset of involuntary breathing movements.

OBJECTIVE: The aim of this study was to measure dynamic lung hyperinflation and its influence on dyspnea perception in moderate and severe chronic obstructive pulmonary disease patients after performing activities of daily living. METHODS: We measured inspiratory capacity, sensation of dyspnea, peripheral oxygen saturation, heart rate and respiratory rate in 19 chronic obstructive pulmonary disease patients. These measurements were taken at rest and after performing activities of daily living (e.g., going up and down a set of stairs, going up and down a ramp and sweeping and mopping a room). RESULT: The inspiratory capacity of patients at rest was significantly decreased compared to the capacity of patients after performing activities. The change in inspiratory capacity was -0.67 L after going up and down a ramp, -0.46 L after sweeping and mopping a room, and -0.55 L after climbing up and down a set of stairs. Dyspnea perception increased significantly between rest, sweeping and mopping, and going up and down a set of stairs. Dyspnea perception correlated positively with inspiratory capacity variation (r = 0.85) and respiratory rate (r = 0.37) and negatively with peripheral oxygen saturation (r = -0.28). CONCLUSION: Chronic obstructive pulmonary disease patients exhibited reductions in inspiratory capacity and increases in dyspnea perception during commonly performed activities of daily living, which may limit physical performance in these patients.

Persistent dyspnoea during daily activities is commonly observed in patient with chronic heart failure (CHF) despite optimised pharmacological therapy. In CHF patients diuretics are essential for symptomatic treatment when fluid overloads with consequent pulmonary congestion or peripheral oedema. Appropriate use of diuretics is key element versus other drugs used for the success of the treatment of HF. Conversely, the inappropriate use of high doses of diuretics can cause adverse effects as electrolyte and fluid depletion, hypotension and hyperazotemia. Dyspnoea and fatigue, in patients with stable HF, are not related only to fluid overload and/or fluid retention but likely other mechanisms are linked to symptoms increase. These patients at the end of a rehabilitative treatment take less diuretic doses than during the period before the rehabilitative treatment, so reducing the principal adverse effects and improving the symptoms. In these patients in absence of venous congestion but in presence of an increase of symptoms augmenting diuretic drugs is not useful: it is very useful, instead, to undergo these patients a rehabilitative treatment because other mechanisms are linked to symptoms increase. In fact, in our report the predominant mechanism determining the increase in dyspnoea is likely related to an increase in physiological dead space.

The optimal selection of patients for lung volume reduction surgery (LVRS) is currently based on empiric clinical findings. Patients who benefit from LVRS have the common characteristics of impaired quality of life associated with apical predominant pulmonary hyperinflation and airflow obstruction. Within this category, patients who do not benefit from LVRS appear to have small airways disease that can be detected by inspiratory resistance studies. In addition to appropriate emphysema physiology, the selection of patients for LVRS must consider medical comorbidities and perioperative risk factors. Based on findings of the National Emphysema Treatment Trial, most of the perioperative morbidity and mortality of LVRS is associated with cardiopulmonary risk that needs to be considered preoperatively. Finally, a preoperative conditioning program can provide an additional screening process to identify patients physically and emotionally prepared for surgery.

Introduction: COPD exacerbation is a life-threatening condition with acute dyspnoea caused by respiratory or circulatory distress. The significance and co-presence of lung hyperinflation, bronchial obstruction, and changes in haemodynamics in the course of COPD exacerbation treatment have not been well described yet in course of a single study. Our aim was to evaluate the influence of COPD exacerbation treatment on bronchial obstruction, pulmonary hyperinflation, and possible changes of right and left ventricle haemodynamics in relation to the patient’s clinical status. Materials and Methods: A total of 40 patients (90% males), 67 ± 8 years old, with COPD were assessed pre- and post-exacerbation treatment by the following: respiratory function tests, transthoracic echocardiography, 6MWT, endothelin-1 (ET-1) and NT-proBNP serum concentrations, and MRC scale. Results: A significant decrease in RV%TLC (%) and mean pulmonary artery pressure (PAPmean) [mm Hg] was observed: pre -RV%TLC: 64.3 ± 9.0; post-RV%TLC 60.6 ± 11.1; p = 0.03; pre-PAPmean: 41.2 ± 11.2; post-PAPmean: 39.1 ± 12.1; p = 0.029, coupled with a significant increase of FEV1 [L]-preFEV1: 1.0 ± 0.4, post-FEV1: 1.2 ± 0.5; p < 0.001. A trend for reduced right ventricle systolic pressure (RVSP) [mm Hg]: pre-treatment: 44.5 ± 12.9; post-treatment: 36.3 ± 14.3; p = 0.068 and ET-1 [fmol/ml]: pre-treatment: 1.7 ± 2.8; post-treatment: 1.3 ± 1.9; p = 0.076, but not for NT-proBNP was noticed. Improvement of both, 6MWT [m]: pre-treatment: 294 ± 132; post-treatment: 415 ± 102; p < 0.001 and MRC [pts.]: pre-treatment: 3.3 ± 0.8; post-treatment: 1.8 ± 0.9; p < 0.001, were noticed. 6MWT correlated with RV%TLC (p < 0.05; r = –0.46; r = –0.53; respectively) and FEV1 (p < 0.05; r = 0.55; r = 0.60, respectively) on admission as well as on discharge. There was no such correlation with RVSP or PAPmean. Conclusions: Pulmonary hyperinflation and bronchial obstruction may be reduced by effective COPD exacerbation treatment and are accompanied by clinical improvement. The mPAP reduction observed in the course of treatment was not correlated with the results of 6MWT and MRC score.

Existen diversos parámetros que pueden ayudar a conocer la mecánica respiratoria del niño sometido a ventilación mecánica. La complianza es una medida de la distensibilidad del sistema respiratorio. En ventilación mecánica puede medirse la complianza estática (distensibilidad del pulmón), en modalidades volumétricas mediante la aplicación de una pausa inspiratoria con el sistema respiratorio en reposo (paciente sedado sin respiración espontánea), o con más frecuencia la complianza dinámica (distensibilidad de todo el sistema respiratorio), que no precisa pausa inspiratoria ni sistema respiratorio en reposo. La complianza puede ser calculada numéricamente o expresada gráficamente en la curva de volumen-presión. Muchos respiradores pueden calcular también la resistencia de la vía aérea (que incluye también la del tubo endotraqueal) durante la inspiración y espiración. Para valorar la existencia de hiperinsuflación dinámica se utilizan diversas medidas (medición de PEEP intrínseca o auto-PEEP, volumen aéreo atrapado) tras la aplicación de una pausa espiratoria prolongada. Los respiradores de última generación permiten realizar estas mediciones de forma casi automática. También es posible medir el trabajo y esfuerzo respiratorio realizado por el paciente mediante el cálculo de diversas medidas (producto de la presión inspiratoria por el tiempo, trabajo respiratorio impuesto, presión 0,1, máximo esfuerzo inspiratorio). Sin embargo, estas medidas no han sido todavía estandarizadas en el paciente pediátrico : Several parameters can be used to study respiratory mechanics in children on mechanical ventilation. Compliance is a measure of the distensibility of the respiratory system. In mechanical ventilation two measures of compliance can be used. Static compliance (pulmonary distensibility) can be measured in volume modes by the application of an inspiratory pause with the respiratory system at rest (sedated patients without inspiratory effort). Dynamic compliance does not require an inspiratory pause and the respiratory system need not be at rest. Compliance can be calculated numerically or expressed graphically in the volume-pressure curve. Many respirators can calculate inspiratory and expiratory airway resistance (including endotracheal tube resistance). Several measures can be used to detect dynamic hyperinflation (intrinsic PEEP, auto-PEEP, trapped air volume) after application of an expiratory pause. The latest respirators can perform these measurements almost automatically. Work of breathing and respiratory effort can also be analyzed by measuring several parameters (pressure-time product, imposed work of breathing, P 0.1, maximum inspiratory pressure). However, these measures have not yet been standardized in children

Las indicaciones de ventilación mecánica en el estado asmático son la parada cardiorrespiratoria, la alteración importante del estado de conciencia, el agotamiento respiratorio y la insuficiencia respiratoria progresiva, a pesar de tratamiento broncodilatador agresivo. La ventilación mecánica (VM) del estado asmático debe aplicar una estrategia específica dirigida a reducir la hiperinsuflación dinámica, con volúmenes corrientes bajos y tiempos espiratorios prolongados, que se consiguen disminuyendo la frecuencia respiratoria. Este patrón ventilatorio condiciona una hipercapnia permisiva, que por lo general es bien tolerada con una sedación adecuada. Los mejores métodos para detectar y/o controlar la hiperinsuflación dinámica en los pacientes con estado asmático ventilados son las curvas de flujo/tiempo y flujo/volumen, el volumen pulmonar al final de la inspiración y la presión meseta. Además de la VM el niño debe recibir sedación con o sin relajación muscular para evitar el barotrauma y la extubación, y tratamiento broncodilatador con betamiméticos, metilprednisolona y teofilina por vía intravenosa y, en los pacientes en los que resulte efectivo, una combinación inhalada de salbutamol e ipratropio nebulizada en la rama inspiratoria del ventilador. En el momento actual no existen suficientes evidencias sobre la efectividad de otros tratamientos en el estado asmático y deben ser considerados como tratamientos de rescate : The indications for mechanical ventilation in status asthmaticus are cardiopulmonary arrest, significant alterations of consciousness, respiratory exhaustion, and progressive respiratory insufficiency despite aggressive bronchodilator treatment. In mechanical ventilation for status asthmaticus, a specific strategy directed at reducing dynamic hyperinflation must be used, with low tidal volumes and long expiratory times, achieved by diminishing respiratory frequency. This ventilatory pattern produces permissive hypercapnia, which is generally well tolerated with suitable sedation. The best methods for detecting and/or controlling dynamic hyperinflation in ventilated patients with status asthmaticus are the flow/time and flow/volume respiratory curves, pulmonary volume at the end of inspiration, and the pressure plateau. In addition to mechanical ventilation the child must receive sedation with or without a muscle relaxant to prevent barotrauma and accidental extubation. Bronchodilator treatment with beta-adrenergic agonists, methylprednisolone, and intravenous aminophylline are also required. A combination of inhaled salbutamol and nebulized ipratropium in the inspiratory branch of the ventilator should be used in patients in whom this treatment is effective. Currently there is insufficient evidence on the efficiency of other treatments in status asthmaticus and these should be used as rescue treatments

RESUMO: A avaliação da eficácia dos broncodilatadores inalados é feita habitualmente pela medição do volume expiratório máximo no primeiro segundo (FEV1) antes e após a administração destes fármacos. Outras medições da função pulmonar, como os volumes pulmonares, não são avaliadas por rotina na maior parte dos laboratórios. Contudo, a compreensão dos efeitos dos broncodilatadores sobre os volumes pulmonares é importante, já que a hiperinsuflação pulmonar é responsável em grande parte por um excessivo trabalho respiratório e pelo aumento da dispneia observados nos doentes com doença pulmonar obstrutiva.Os autores começam por apontar o FEV1 como um marcador que pode ser pouco sensível à resposta aos broncodilatadores e dão como exemplos de parâmetros mais sensíveis a capacidade inspiratória e a avaliação das curvas débito-volume parciais. Salientam a vantagem da capacidade inspiratória relativamente ao FEV1, como factor preditivo da melhoria da tolerância ao exercício e da dispneia.No presente estudo, os autores avaliam os padrões de resposta dos volumes pulmonares â capacidade residual funcional (FRC), volume residual (RV), capacidade vital forçada (FVC) e capacidade inspiratória (IC) â aos broncodilatadores inalados em doentes com hiperinsuflação pulmonar moderada e grave devida primariamente à doença pulmonar obstrutiva crónica (DPOC).Realizaram um estudo retrospectivo que envolveu 957 doentes (534 homens, 423 mulheres; idade: 64,7±0,37 anos), sendo 281 gravemente hiperinsuflados (TLC > 133% do teórico, FEV1 /FVC% < 85% do teórico) e os restantes 676 moderadamente hiperinsuflados (TLC entre 115% e 133% do teórico, FEV1 / FVC% < 85% do teórico).Em todos os doentes foi realizado um estudo funcional respiratório completo antes e após a administração de 200 ¼ g de salbutamol.Caracterizaram a resposta aos broncodilatadores em termos de resposta dos débitos e resposta dos volumes. A resposta dos débitos foi determinada pela variação do FEV 1. A resposta dos volumes foi avaliada pela variação da IC, do RV e da FVC. Ocorreu uma resposta dos débitos em 33% dos doentes gravemente hiperinsuflados e em 26% dos doentes moderadamente hiperinsuflados. A resposta dos volumes verificou-se em 76% dos doentes gravemente hiperinsuflados e em 62% dos doentes moderadamente hiperinsuflados. Dezassete por cento dos doentes moderadamente hiperinsuflados e 26% dos doentes gravemente hiperinsuflados apenas melhoraram a capacidade inspiratória. Para avaliar a utilidade específica dos volumes pulmonares estáticos como marcadores da resposta aos broncodilatadores foram avaliadas as respostas dos volumes (RV+IC) nos doentes que não apresentaram qualquer melhoria dos débitos. Verificaram que 35% dos doentes moderadamente hiperinsuflados e 63% dos doentes gravemente hiperin-suflados melhoraram significativamente os volumes pulmonares.Este estudo permitiu evidenciar que a medição dos volumes pulmonares (IC, RV, FVC) antes e após a administração de broncodilatadores identifica um tipo de resposta que não podia ser detectada pela medição tradicional do FEV1, sugerindo que cerca de três quartos destes doentes melhoram com a terapêutica broncodilatadora. A melhoria observada nos volumes pulmonares foi independente das alterações dos débitos das vias aéreas.Embora tradicionalmente utilizado como marcador de reversibilidade, o FEV1 tem demonstrado, em alguns casos, reduzida sensibilidade, e é um factor pouco preditivo da tolerância ao exercício no doente com DPOC avançada.A resposta do FEV1 aos broncodilatadores pode ser mascarada durante a manobra de expiração máxima forçada devido à compressão do gás intratorácico e das vias aéreas, sobretudo se a pressão de retracção elástica estiver reduzida, como ocorre no enfisema. Como resultado, a medição dos débitos expiratórios parciais pode ser mais sensível aos broncodilatadores do que a medição dos débitos expiratórios máximos.Os achados destes autores indicam que a não medição dos volumes pulmonares leva a perda de informação de um efeito broncodilatador importante. Assumir que apenas o FEV1 é importante implicava neste estudo a exclusão de 50% dos doentes que obtiveram melhoria significativa da IC.Os autores concluem que uma dose relativamente pequena de salbutamol inalado reduziu a hiperinsuflação e o âair-trappingâ em doentes com hiperinsuflação basal significativa, mesmo naqueles em estádio avançado de doença. Com efeito, a resposta mais exuberante verificou-se precisamente nos doentes mais graves.Propõem que a avaliação da resposta aos broncodilatadores, bem como da eficácia de novos tratamentos, deve incluir não só os parâmetros espirométricos mas também o estudo dos volumes pulmonares, em particular nos doentes com hiperinsuflação pulmonar. COMENTÃRIO: A avaliação âtradicionalâ da resposta aos broncodilatadores assenta na medição da variação do FEV1, da capacidade vital ou da resistência das vias aéreas1. A justificação apontada para a preferência na medição do FEV1 tem sido o facto de este parâmetro ser reprodutível (em diferentes medições realizadas nas mesmas circunstâncias resultam valores semelhantes) e apresentar uma boa sensibilidade, quando comparado com outros parâmetros, como a resistência das vias aéreas que embora seja um parâmetro mais sensível, apresenta uma menor reprodutibilidade e maior dependência dos volumes pulmonares na altura da medição1.Brand et al2 estudaram várias expressões da resposta à broncodilatação avaliada pela variação do FEV1 (como percentagem do FEV1 basal, como valor absoluto em litros, como percentagem do FEV1 teórico previsto, como o residual estandardizado e como o aumento máximo possível) em doentes com patologia obstrutiva das vias aéreas e concluíram que a variação do FEV1 como percentagem do valor teórico previsto parece ser o método mais útil de expressar a resposta à broncodilatação quer para objectivos clínicos quer de investigação, pois não depende do valor do FEV1 basal. A dependência do valor de FEV 1 basal (exemplo: a avaliação da variação do FEV1 como percentagem do FEV1 basal) dava uma ideia menos exacta da resposta à broncodilatação porque evidenciava uma maior resposta nos doentes mais obstruídos, o que fazia prever um melhor prognóstico, não sendo este rea12. A avaliação da resposta aos broncodilatadores pela variação do FEV1 deve pois ser rigorosa. Mas será suficiente?à frequente observar-se dissociação entre a clínica e a avaliação funcional respiratória: Doentes emquem não se observa melhoria do FEV1 com a administração dos broncodilatadores referem contudo melhoria clínica. Uma resposta negativa aos broncodilatadores inalados não exclui pois beneficio clínico, por exemplo em termos de melhoria da dispneia ou do aumento da distância percorrida na prova de marcha4. Esta poderá ser devida, na perspectiva dos autores deste trabalho, à melhoria funcional relacionada com os volumes pulmonares. A redução da hiperinsuflação e do âair-trappingâ pode associar-se a alívio sintomático significativo.A DPOC é caracterizada por uma redução do FEV1 que não responde ou responde mal aos broncodilatadores â o que a diferencia da asma, â mas, paradoxalmente, continuamos a usar o FEV1 para avaliar os efeitos da terapêutica3. Esta abordagem esquizóide é, segundo B. Celli, única em Medicina, e pode equivaler a definir hipertensão essencial como um aumento da pressão arterial que não responde à terapêutica anti-hipertensora, mas continuar a testar os agentes anti-hipertensores usando como único parâmetro de avaliação de eficácia, a pressão arterial não modificável2. O FEV1 medido após a broncodilatação é um parâmetro que se correlaciona com a mortalidade (queda anual superior a 30 a 50 ml), mas é sobretudo quando desce abaixo de 50% do valor teórico previsto que a mortalidade começa a aumentar. São necessários outros parâmetros funcionais e clínicos para avaliar em cada doente o grau de gravidade da sua doença, para estudos clínicos e epidemiológicos, planeamento dos recursos de saúde e avaliação do prognóstico. Este autor sugere a adopção de um novo sistema de categorização dos doentes com DPOC que inclui factores reconhecidamente associados ao prognóstico, como o estado de nutrição (Ãndice de Massa Corporal), Obstrução (FEV 1), avaliação dos sintomas (Dispneia) e avaliação da tolerância ao exercício em endurance (Prova de marcha de 6 minutos). Este sistema designado por BODE: Body mass index, Obstruction, Dyspnea, Endurance, engloba a avaliação da percepção (dispneia), a avaliação respiratória (FEV1 e gasometria arterial) e a avaliação sistémica (nutricional ecapacidade para o exercício) e está actualmente a ser testado em 3 países. Segundo B. Celli é uma forma mais rigorosa de avaliar o doente com DPOC, sendo o seu score sensível aos efeitos da terapêutica 5.O uso exclusivo do FEV 1 na avaliação da resposta aos broncodilatadores poderá ter uma utilidade questionável na DPOC, pois não separa de forma segura a asma da DPOC, havendo sobreposição de respostas nestas duas entidades; não prediz as respostas clínicas ao tratamento, sendo outros parâmetros, como a capacidade inspiratória, aparentemente mais correlacionáveis com a clínica (capacidade para o exercício) e não é um factor preditivo do prognóstico, sendo ultrapassado por exemplo, pela queda anual do FEV14.Os autores deste trabalho propõem para a avaliação da broncodilatação a medição dos volumes pulmonares, particularmente em doentes com hiperinsuflação pulmonar.Vejamos então o que se passa nestes doentes:A hiperinsuflação pulmonar, pelo abaixamento e horizontalização do diafragma, coloca os músculos respiratórios em desvantagem mecânica, conduzindo a fraqueza muscular; provoca alteração do padrão ventilatório, que se torna mais rápido e superficial e conduz ao aparecimento de dispneia de esforço.Belman et al6 demonstraram que a terapêutica broncodilatadora permite a redução do âair-trappingâ e melhora a capacidade inspiratória em repouso e durante o exercício físico em doentes com DPOC, o que lhes permite atingirem ou mesmo ultrapassarem os níveis de ventilação necessários ao exercício mas com menores volumes operacionais e com um padrão ventilatório mais eficiente (mais lento e profundo). Como consequência, obtém-se uma redução da carga elástica do sistema respiratório e um aumento da força dos músculos respiratórios, o que leva à redução da dispneia e melhoria da tolerância ao exercício físico6,7. Têm sido demonstrados benefícios mecânicos e sintomáticos evidentes com todas as classes de broncodilatadores. Em muitos destes casos, a alteração do FEV1 é mínima ou nula6,7. Palavras-chave: Broncodilatadores, Volumes pulmonares, Doenças pulmonares obstrutivas, Hiperinsuflação pulmonar, Key-words: Bronchodilator agents, Lung volume measurements, Obstructive lung diseases, Pulmonary hyperinflation

Acute exacerbation of COPD is most often caused by pulmonary infections. This may necessitate support by mechanical ventilation (non-invasively via nasal or face mask or invasively via endotracheal tube). For ventilation settings and strategy, a profound understanding of the pathophysiological mechanisms is mandatory. The main principles are reducing dynamic pulmonary hyperinflation, decreasing work of breathing by reduction of obstructive load, and avoiding patient-ventilator dyscoordination. Careful and repeated adjustment of the ventilator settings is mandatory. After the acute phase, the weaning process has to be initiated as early as possible.

Two aged dogs with chronic obstructive airway disease were evaluated because of intermittent swelling of the ventral cervical region. Radiographs made at expiration and caudal positioning of the forelimbs allowed identification of intermittent cervical lung herniation of the left and right cranial lung lobe in both dogs. Pulmonary hyperinflation, increased expiratory effort, and chronic coughing were considered responsible for the lung herniation. Cervical lung hernia should be included in the differential diagnoses of intermittent cervical swelling in dogs with chronic respiratory disorders associated with increased expiratory effort and chronic coughing.