Applications of oscillometry in clinical research and practice

Abstract

Oscillometry is gaining in clinical use and while there is an increased interest in the technique, there is paucity in the understanding of its possibilities and limitations. Oscillometry has seen extensive use in research over several decades, but only recently is the technique being adopted in clinical practice; hence, there is a need to educate the novel users. The goal of the mini symposium arranged in San Diego in 2018 was to discuss the principles of oscillometry, showcase some of the recent ongoing research using this technique and to demonstrate how oscillometry may be used in clinical practice. It was concluded that oscillometry has several advantages over spirometry, most notably, with novel data being shown, its sensitivity allowing early detection of small airways disease not possible with spirometry and it can be used in subjects who have difficulties performing forced maneuvers such as preschool children, the elderly and subjects with handicaps. The site of respiratory pathology can be reflected by the various parameters generated by oscillometry and thus help with both disease diagnosis and localization. While the interpretation of oscillometry parameters and translating them into meaningful pathological correlates is still evolving, it is likely that oscillometry will soon be at the forefront of both pulmonary clinical practice and research. R ESUM EL'oscillom etrie est de plus en plus utilis ee en contexte clinique, mais malgr e l'int erêt accru pour cette technique, la compr ehension de ses possibilit es et de ses limites est encore insuffisante. Pendant plusieurs d ecennies, l'oscillom etrie a largement et e utilis ee dans la recherche, mais l'adoption de cette technique dans la pratique clinique est encore r ecente, de sorte qu'il est n ecessaire de former les nouveaux utilisateurs. Le but de ce mini symposium qui s'est tenu a San Diego en 2018 etait de discuter des principes de l'oscillom etrie, de pr esenter les plus r ecentes etudes utilisant cette technique et de d emontrer comment elle peutêtre utilis ee dans la pratique clinique. Il a et e d etermin e que l'oscillom etrie pr esentait plusieurs avantages par rapport a la spirom etrie notamment, comme le d emontrent de nouvelles donn ees, sa sensibilit e qui permet la d etection pr ecoce de la maladie des petites voies a eriennes, ce que la spirom etrie ne peut pas faire, ainsi que le fait qu'elle puisseêtre utilis ee aupr es de sujets qui eprouvent de la difficult e a effectuer des manoeuvres forc ees comme les enfants d'âge pr escolaire, les personnesâg ees et les personnes atteintes d'un handicap. L'emplacement de la pathologie respiratoire peut se refl eter dans les divers param etres produits par la spirom etrie, ce qui peut contribuer a diagnostiquer la maladie et a la localiser. Bien que l'interpr etation des param etres de l'oscillom etrie et leur traduction dans des corr elats pathologiques significatifs continue d' evoluer, l'oscillom etrie sera vraisemblablement a l'avant-plan de la pratique clinique et de la recherche pulmonair...

Chronic exposure to diesel exhaust may cause small airway wall thickening without lumen narrowing: a quantitative computerized tomography study in Chinese diesel engine testers

“…However, we plan to include end-inhalation CT in our future follow-up visits for these DETs and will include older or retired DETs to characterize the temporal change of lung tissue remodeling including air trapping. In addition, oscillometry which is effort-independent and sensitive to small airway changes will be included in addition to spirometry in our future studies of particulate matter exposure [ 38 ].…”

Oscillometry of the respiratory system: a translational opportunity not to be missed

“…From a functional point of view, these changes lead to the generation of an emphysematous phenotype characterized by a change in tissue elastance (parameter H) when assessed by oscillometry. This means, as explained above, that the main changes are found in the reactance part of the impedance, as seen in human COPD patients (57,124,175). One important difference between the two species, however, resides in the severity of the induced lesions, which are more subtle in most mice models especially following tobacco smoke exposure and despite long exposure periods (33,201,202).…”

“…The principles behind the technique are derived from an engineering approach of characterizing systems in movement and have been the subject of a number of previous review articles and books (12,15,46,124,154,156). In brief, information about the system studied (e.g., the respiratory system) is obtained by studying the deformation of an imposed input signal going through it, the amount of change being commensurate to the overall opposition exerted by the system.…”

“…In a disease such as chronic obstructive pulmonary disease (COPD) with peripheral airway obstruction, which tends to be heterogenous and can be understood as a distribution of pathway resistances, the resistance part of the respiratory impedance curve becomes frequency-dependent and displays an increase more towards lower frequency range (Figure 1B). Thus, the difference between resistance at low and higher | P a g e frequencies (R 5-20 ) becomes a measure of airway heterogeneity and typically increases with small airways obstruction (34,42,59,72,107,124,153,200). At 5 Hz, the reactance (X 5 ) is influenced by the elastic properties of the respiratory system where it reflects the soft tissue and lung parenchyma.…”

Long term impact of coal mine fire smoke on lung mechanics in exposed adults

“…FOT may be able to detect early changes in peripheral airway function that spirometry cannot. [8] To our knowledge, no study has assessed the long-term impact of PM 2.5 from exposure to coal mine fires, wildfires, or biomass fuel smoke in adults using FOT.…”