Mechanisms, measurement and management of exertional dyspnoea in asthma

Abstract

Asthma is a heterogeneous condition, with dyspnoea during exercise affecting individuals to a variable degree. This narrative review explores the mechanisms and measurement of exertional dyspnoea in asthma and summarises the available evidence for the efficacy of various interventions on exertional dyspnoea. Studies on the mechanisms of dyspnoea in asthma have largely utilised direct bronchoprovocation challenges, rather than exercise, which may invoke different physiological mechanisms. Thus, the description of dyspnoea during methacholine challenge can differ from what is experienced during daily activities, including exercise. Dyspnoea perception during exercise is influenced by many interacting variables, such as asthma severity and phenotype, bronchoconstriction, dynamic hyperinflation, respiratory drive and psychological factors. In addition to the intensity of dyspnoea, the qualitative description of dyspnoea may give important clues as to the underlying mechanism and may be an important endpoint for future interventional studies. There is currently little evidence demonstrating whether pharmacological or non-pharmacological interventions specifically improve exertional dyspnoea, which is an important area for future research.

Improvement of exertional dyspnea and breathing pattern of inspiration to expiration after bronchial thermoplasty

“…However, the mechanisms by which BT improves the subjective symptoms of asthma without significantly changing the resting pulmonary function [ 6 , 8 ] are yet to be elucidated. Exertional dyspnea is a common symptom in asthma, and the mechanisms of it in asthma are complex [ 10 ]. In the present case, we focused on the pattern of exertional ventilation because minute ventilation ( ) decreased during exercise after BT (Fig.…”

“…2 a). Although not all asthmatics develop dynamic hyperinflation (DH) [ 10 ], before BT in this case, the patient presented with DH during mid-exercise at pre-BT, because, based on the finding that the expiratory tidal volume (V Tex ) reached a plateau followed by a sharp increase in respiratory frequency (f R ). At 1 year after BT, the breathing pattern of DH improved (Fig.…”

Clinical scale to assess of bronchial obstruction severity at preschoolers

“…Ряд авторов сравнивают восприятие одышки с ощущениями, возникающими при боли [38]. Восприятие одышки описывается пациента-ми по-разному: нехватка воздуха, затрудненное дыхание, невозможность сделать глубокий вдох (выдох) [39]. У детей раннего возраста косвенно о наличии одышки можно судить по поведению ребенка: беспокойство, растерянность, скандиро-ванная речь, вынужденное положение, отказ от еды.…”

Dusulio intensyvumo sąsajos su eozinofilų skaičiumi kraujyje sergant alergine astma

“…vimo raumenų proprioreceptorių, tiesioginio kvėpavimo takų mechanoreceptorių stimuliavimo [1,[10][11][12][13]. Dusulio suvokimui reikšmingos įtakos turi ir eozinofilinis kvėpavimo takų uždegimas [1,3,14].…”

“…Žinoma, kad aktyvuoti eozinofilai išskiria neurotoksinus, kurie veikia aferentinius nervus, dalyvaujančius dusulio suvokime [12]. Smulkiųjų kvėpavimo takų uždegiminis procesas didina plaučių hiperinfliaciją ir ankstyvą kvėpavimo takų užsidarymą [1,[10][11][12][13]. Įrodyta, kad pacientams, sergantiems sunkia astma su pasikartojančiais paūmėjimais, smulkiųjų kvėpavimo takų obstrukcija buvo ryškesnė [1].…”