Physiological Characterization of Preserved Ratio Impaired Spirometry in the CanCOLD Study: Implications for Exertional Dyspnea and Exercise Intolerance.

It is increasingly recognized that adults with preserved ratio impaired spirometry (PRISm) are prone to increased morbidity. However, the underlying pathophysiological mechanisms are unknown. Evaluate the mechanisms of increased dyspnea and reduced exercise capacity in PRISm.

ERS International Congress 2022: highlights from the Sleep Disordered Breathing Assembly.

During the European Respiratory Society (ERS) International Congress 2022 in Barcelona, Spain, the latest research and clinical topics in respiratory medicine were presented. The sleep medicine-focused presentations and symposia provided novel insights into the pathophysiology of sleep disordered breathing, its diagnostics, and new trends in translational research and clinical applications. The presented research trends focused mainly on the assessment of sleep disordered breathing-related intermittent hypoxia, inflammation and sleep fragmentation, and their implications, especially cardiovascular.

Pulmonary Vascular Volume by Quantitative CT in Dyspneic Smokers with Minor Emphysema.

Reduced lung diffusing capacity for carbon monoxide (DL) at rest and increased ventilation ()-carbon dioxide output (CO) during exercise are frequent findings in dyspneic smokers with largely preserved FEV. It remains unclear whether low DL and high -CO are mere reflections of alveolar destruction (i.e.

Exercise Intolerance in Untreated OSA: Role of Pulmonary Gas Exchange and Systemic Vascular Abnormalities.

Background: Reduced exercise capacity has been reported previously in patients with OSA hypopnea syndrome (OSAHS), although the underlying mechanisms are unclear.

Research Question: What are the underlying mechanisms of reduced exercise capacity in untreated patients with OSAHS? Is there a role for systemic or pulmonary vascular abnormalities?

Study Design And Methods: This was a cross-sectional observational study in which 14 patients with moderate to severe OSAHS and 10 control participants (matched for age, BMI, smoking history, and FEV) underwent spirometry, incremental cycle cardiopulmonary exercise test (CPET) with arterial line, resting echocardiography, and assessment of arterial stiffness (pulse wave velocity [PWV] and augmentation index [AIx]).

Results: Patients (age, 50 ± 11 years; BMI, 30.

Impaired Ventilatory Efficiency, Dyspnea, and Exercise Intolerance in Chronic Obstructive Pulmonary Disease: Results from the CanCOLD Study.

Impaired exercise ventilatory efficiency (high ventilatory requirements for CO [[Formula: see text]e/[Formula: see text]co]) provides an indication of pulmonary gas exchange abnormalities in chronic obstructive pulmonary disease (COPD). To determine ) the association between high [Formula: see text]e/[Formula: see text]co and clinical outcomes (dyspnea and exercise capacity) and its relationship to lung function and structural radiographic abnormalities; and ) its prevalence in a large population-based cohort. Participants were recruited randomly from the population and underwent clinical evaluation, pulmonary function, cardiopulmonary exercise testing, and chest computed tomography.

Compensatory responses to increased mechanical abnormalities in COPD during sleep.

Purpose: To assess whether night-time increases in mechanical loading negatively impact respiratory muscle function in COPD and whether compensatory increases in inspiratory neural drive (IND) are adequate to stabilize ventilatory output and arterial oxygen saturation, especially during sleep when wakefulness drive is withdrawn.

Methods: 21 patients with moderate-to-severe COPD and 20 age-/sex-matched healthy controls (CTRL) participated in a prospective, cross-sectional, one-night study to assess the impact of COPD on serial awake, supine inspiratory capacity (IC) measurements and continuous dynamic respiratory muscle function (esophageal manometry) and IND (diaphragm electromyography, EMGdi) in supine sleep.

Results: Supine inspiratory effort and EMGdi were consistently twice as high in COPD versus CTRL (p < 0.

Qualitative Components of Dyspnea during Incremental Exercise across the COPD Continuum.

Introduction: Evaluation of the intensity and quality of activity-related dyspnea is potentially useful in people with chronic obstructive pulmonary disease (COPD). The present study sought to examine associations between qualitative dyspnea descriptors, dyspnea intensity ratings, dynamic respiratory mechanics, and exercise capacity during cardiopulmonary exercise testing (CPET) in COPD and healthy controls.

Methods: In this cross-sectional study, 261 patients with mild-to-very severe COPD (forced expiratory volume in 1 s, 62 ± 25%pred) and 94 age-matched controls (forced expiratory volume in 1 s, 114 ± 14%pred) completed an incremental cycle CPET to determine peak oxygen uptake (V˙O2peak).

Mechanisms of Exertional Dyspnea in Patients with Mild COPD and a Low Resting DL.

Patients with mild chronic obstructive pulmonary disease (COPD) and lower resting diffusing capacity for carbon monoxide (DL) often report troublesome dyspnea during exercise although the mechanisms are not clear. We postulated that in such individuals, exertional dyspnea is linked to relatively high inspiratory neural drive (IND) due, in part, to the effects of reduced ventilatory efficiency. This cross-sectional study included 28 patients with GOLD I COPD stratified into two groups with ( = 15) and without ( = 13) DL less than the lower limit of normal ( View Article and Find Full Text PDF

Sleep quality and architecture in COPD: the relationship with lung function abnormalities.

Objective: Impaired respiratory mechanics and gas exchange may contribute to sleep disturbance in patients with COPD. We aimed to assess putative associations of different domains of lung function (airflow limitation, lung volumes, and gas exchange efficiency) with polysomnography (PSG)-derived parameters of sleep quality and architecture in COPD.

Methods: We retrospectively assessed data from COPD 181 patients ≥ 40 years of age who underwent spirometry, plethysmography, and overnight PSG.

Reduced exercise tolerance in mild chronic obstructive pulmonary disease: The contribution of combined abnormalities of diffusing capacity for carbon monoxide and ventilatory efficiency.

Background And Objective: The combination of both reduced resting diffusing capacity of the lung for carbon monoxide (DL ) and ventilatory efficiency (increased ventilatory requirement for CO clearance [V˙ /V˙CO ]) has been linked to exertional dyspnoea and exercise intolerance in chronic obstructive pulmonary disease (COPD) but the underlying mechanisms are poorly understood. The current study examined if low resting DL and higher exercise ventilatory requirements were associated with earlier critical dynamic mechanical constraints, dyspnoea and exercise limitation in patients with mild COPD.

Methods: In this retrospective analysis, we compared V˙ /V˙CO , dynamic inspiratory reserve volume (IRV), dyspnoea and exercise capacity in groups of patients with Global Initiative for Chronic Obstructive Lung Disease stage 1 COPD with (1) a resting DL at or greater than the lower limit of normal (≥LLN; Global Lung Function Initiative reference equations [n = 44]) or (2) below the View Article and Find Full Text PDF

European Respiratory Society International Congress 2020: highlights from best-abstract awardees.

https://bit.ly/3kJ9JrJ.

Elevated exercise ventilation in mild COPD is not linked to enhanced central chemosensitivity.

Background: The purpose of this study was to determine if altered central chemoreceptor characteristics contributed to the elevated ventilation relative to carbon dioxide production (V̇/V̇CO) response during exercise in mild chronic obstructive pulmonary disease (COPD).

Methods: Twenty-nine mild COPD and 19 healthy age-matched control participants undertook lung function testing followed by symptom-limited incremental cardiopulmonary exercise testing . On a separate day, basal (non-chemoreflex) ventilation (V̇), the central chemoreflex ventilatory recruitment threshold for CO (VRTCO), and central chemoreflex sensitivity (V̇) were assessed using the modified Duffin's CO rebreathing method.

Mechanisms of orthopnoea in patients with advanced COPD.

Many patients with severe chronic obstructive pulmonary disease (COPD) report an unpleasant respiratory sensation at rest, which is further amplified by adoption of a supine position (orthopnoea). The mechanisms of this acute symptomatic deterioration are poorly understood.Sixteen patients with advanced COPD and a history of orthopnoea and 16 age- and sex-matched healthy controls underwent pulmonary function tests (PFTs) and detailed sensory-mechanical measurements including inspiratory neural drive (IND) assessed by diaphragm electromyography (EMG), oesophageal pressure ( ) and gastric pressure ( ), in both sitting and supine positions.

Deterioration of Nighttime Respiratory Mechanics in COPD: Impact of Bronchodilator Therapy.

Background: COPD is associated with nighttime respiratory symptoms, poor sleep quality, and increased risk of nocturnal death. Overnight deterioration of inspiratory capacity (IC) and FEV have been documented previously. However, the precise nature of this deterioration and mechanisms by which evening bronchodilation may mitigate this occurrence have not been studied.

Impact of a Specialized Ambulatory Clinic on Refractory Breathlessness in Subjects With Advanced COPD.

Background: Severe exertional dyspnea is a commonly reported symptom in patients with COPD, especially in the advanced stages. Our objective was to assess the preliminary impact of comprehensive, individualized management provided by a specialized tertiary center clinic on exertional dyspnea and patient-centered outcomes in patients with advanced COPD.

Methods: This retrospective analysis included 45 subjects with COPD who were evaluated in a newly established dyspnea clinic over 3 years.

Eligibility for Lung Volume Reduction Surgery in Patients With COPD Identified in a UK Primary Care Setting.

Background: Although lung volume reduction surgery (LVRS) improves survival in appropriately selected patients with COPD, few procedures are performed. The National Institute for Health and Care Excellence has recommended a more systematic approach to identifying potential candidates. We investigated LVRS referrals from a UK primary care population and aimed to establish an accurate estimate of eligible patients and determine a strategy for identifying potential candidates systematically.

Low resting diffusion capacity, dyspnea, and exercise intolerance in chronic obstructive pulmonary disease.

The mechanisms linking reduced diffusing capacity of the lung for carbon monoxide (Dl) to dyspnea and exercise intolerance across the chronic obstructive pulmonary disease (COPD) continuum are poorly understood. COPD progression generally involves both Dl decline and worsening respiratory mechanics, and their relative contribution to dyspnea has not been determined. In a retrospective analysis of 300 COPD patients who completed symptom-limited incremental cardiopulmonary exercise tests, we tested the association between peak oxygen-uptake (V̇o), Dl, and other resting physiological measures.

Patterns of breathlessness and associated consulting behaviour: results of an online survey.

The online British Lung Foundation Breath Test provides an opportunity to study the relationship between breathlessness, common sociobehavioural risk factors and interaction with healthcare. We analysed data from 356 799 responders: 71% were ≥50 years old and 18% were smokers. 20% reported limiting breathlessness (Medical Research Council breathlessness score ≥3), and the majority of these (85%) worried about their breathing; of these, 29% had not sought medical advice.

Acute bronchodilator therapy does not reduce wasted ventilation during exercise in COPD.

This randomized, double-blind, crossover study aimed to determine if acute treatment with inhaled bronchodilators, by improving regional lung hyperinflation and ventilation distribution, would reduce dead space-to-tidal volume ratio (V/V); thus contributing to improved exertional dyspnea in COPD. Twenty COPD patients (FEV = 50 ± 15% predicted; mean ± SD) performed pulmonary function tests and symptom-limited constant-work rate exercise at 75% peak-work rate (with arterialized capillary blood gases) after nebulized bronchodilator (BD; ipratropium 0.5mg + salbutamol 2.