Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD

Abstract

BackgroundSalbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.MethodsFive patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.ResultsLung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.ConclusionThis pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics.

The Effects of Extrafine Beclometasone/Formoterol (BDP/F) on Lung Function, Dyspnea, Hyperinflation, and Airway Geometry in COPD Patients: Novel Insight Using Functional Respiratory Imaging

“…More details on the segmentation and CFD principles can be found in previously published studies. (7)(8)(9)(10)19) …”

“…Therefore, the use of FRI may allow following the functional and anatomic changes in the small airways after pharmacological interventions both in asthmatics and COPD patients. (7)(8)(9)(10) During the last 10 years, inhaled corticosteroids (ICS) and long-acting b 2 agonists (LABA) combination therapy has come forward to treat COPD patients. The concomitant use of ICS and LABA can influence airway obstruction, mucociliary dysfunction, and airway inflammation.…”

Multi-scale computational models of the airways to unravel the pathophysiological mechanisms in asthma and chronic obstructive pulmonary disease (AirPROM)

“…Following the changes in these image-based outcome parameters provides a strong indication of the efficiency and response to therapies ( figure 3). In previous studies, this concept has been applied to long-acting b 2 -agonists (LABAs) [32], a combination of a LABA and an inhaled corticosteroid [30], a short-acting anticholinergic, a short-acting b 2 -agonist [31] and non-invasive ventilation [33]. The concept has been validated using gamma scintigraphy [34], single-photon emission computed tomography [35] and HP MRI [36].…”

“…Although airway remodelling is assumed Figure 3. Changes in airway volume based on segmented airways from CT scans in a patient (a) mainly responsive to salbutamol and (b) less to ipratropium bromide, and in a patient (c) more responsive to ipratropium bromide and (d ) less responsive to salbutamol [31]. Colour spectrums illustrate the change in local airway volume after treatment (%).…”

Determination of regional lung air volume distribution at mid-tidal breathing from computed tomography: a retrospective study of normal variability and reproducibility

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