Vital capacity and inspiratory capacity as additional parameters to evaluate bronchodilator response in asthmatic patients: a cross sectional study

Abstract

BackgroundBronchodilator response in patients with asthma is evaluated based on post-bronchodilator increase in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). However, the need for additional parameters, mainly among patients with severe asthma, has already been demonstrated.MethodsThe aim of this study was to evaluate the usefulness of vital capacity (VC) and inspiratory capacity (IC) to evaluate bronchodilator response in asthma patients with persistent airflow obstruction. The 43 asthma patients enrolled in the study were stratified into moderate or severe airflow obstruction groups based on baseline FEV1. All patients performed a 6-minute walk test before and after the bronchodilator (BD). A bipolar visual analogue scale post-BD was performed to assess clinical effect. The correlation between VC and IC and clinical response, determined by visual analogue scale (VAS) and 6-minute walk test (6MWT), was investigated.ResultsPatients in the severe group presented: 1) greater bronchodilator response in VC (48% vs 15%, p = 0.02), 2) a significant correlation between VC variation and the reduction in air trapping (Rs = 0.70; p < 0.01), 3) a significant agreement between VC and VAS score (kappa = 0.57; p < 0.01). There was no correlation between IC and the reduction in air trapping or clinical data.ConclusionsVC may be a useful additional parameter to evaluate bronchodilator response in asthma patients with severe airflow obstruction.

Prevalence and reversibility of lung hyperinflation in adult asthmatics with poorly controlled disease or significant dyspnea

“…However, other measures of lung function (such as lung volumes) are not routinely assessed in asthma. A study of 43 asthmatic subjects demonstrated a reduction in RV and RV/TLC after bronchodilator administration, which was greater in those with severe baseline airflow obstruction (as in our study population) . Newton et al also reported a predominant pattern of volume responses in a mixed population of COPD and asthma patients with severe HI at baseline (TLC >130% of predicted)—thus showing that measurements of lung volumes before and after bronchodilators may provide additional criteria for defining responsiveness to bronchodilators .…”

“…During episodes of airflow obstruction, a combination of limited expiratory airflow and closure of the distal airways may induce dynamic lung hyperinflation (HI) because the end‐expiratory lung volume will exceed the functional residual capacity (FRC) . In theory, an increase in the residual volume (RV) is the first step in HI , although the natural history of HI remains poorly defined in both asthma and chronic obstructive pulmonary disease (COPD) . The mechanisms underlying lung HI in asthmatics may also include the activation of inspiratory muscles at the end of expiration in response to bronchoconstriction .…”

“…In contrast, reversibility in asthma is still usually judged in terms of an increase in FEV 1 . However, some patients may feel better even in the absence of such an improvement . It is therefore also important to assess changes in lung volumes when evaluating the clinical efficacy of a bronchodilator in asthma.…”

Parasternal intercostal muscle activity during methacholine‐induced bronchoconstriction

“…; Azevedo et al . ) and, thus, the potential for heterogeneity in the pathophysiological changes between these different study settings must be recognized. Further exploration of the influence of hyperinflation and airflow obstruction within clinical populations would be of interest.…”

Effect of Vertical Oscillatory Pressure on Pain Intensity and Respiratory Variables in Patients with Cervical Spondylosis

“…Respiratory rate is the number of breath per minute (O' Leary et al, 2015). Vital capacity is the maximum volume of air that can be forcefully expired into a spirometer after a maximal inspiration (Azevedo et al, 2012). Many studies have examined the effects of VOP on pain intensity of patients with cervical spondylosis (Ojoawo et al, 2016;Ojoawo et al, 2013).…”