Rheological analysis of sputum from patients with chronic bronchial diseases

Abstract Bronchial diseases are characterised by the weak efficiency of mucus transport through the lower airways, leading in some cases to the muco-obstruction of bronchi. It has been hypothesised that this loss of clearance results from alterations in the mucus rheology, which are reflected in sputum samples collected from patients, making sputum rheology a possible biophysical marker of these diseases and their evolution. However, previous rheological studies have focused on quasi-static viscoelastic (linear storage and loss moduli) properties only, which are not representative of the mucus mobilisation within the respiratory tract. In this paper, we extend this approach further, by analysing both quasi-static and some dynamic (flow point) properties, to assess their usability and relative performance in characterising several chronic bronchial diseases (asthma, chronic obstructive pulmonary disease, and cystic fibrosis) and distinguishing them from healthy subjects. We demonstrate that pathologies influence substantially the linear and flow properties. Linear moduli are weakly condition-specific and even though the corresponding ranges overlap, distinct levels can be identified. This directly relates to the specific mucus structure in each case. In contrast, the flow point is found to strongly increase in muco-obstructive diseases, which may reflect the complete failure of mucociliary clearance causing episodic obstructions. These results suggest that the analysis of quasi-static and dynamic regimes in sputum rheology is in fact useful as these regimes provide complementary markers of chronic bronchial diseases.

Download Full-text

Nanoparticle diffusion in spontaneously expectorated sputum as a biophysical tool to probe disease severity in COPD

European Respiratory Journal ◽

10.1183/13993003.00088-2019 ◽

2019 ◽

Vol 54 (2) ◽

pp. 1900088 ◽

Cited By ~ 5

Author(s):

Jane F. Chisholm ◽

Siddharth K. Shenoy ◽

Julie K. Shade ◽

Victor Kim ◽

Nirupama Putcha ◽

...

Keyword(s):

Lung Function ◽

Disease Severity ◽

Mesh Size ◽

Chronic Obstructive ◽

Lung Function Decline ◽

Obstructive Pulmonary Disease ◽

Mesh Structure ◽

Mucus Rheology ◽

The Mean ◽

Multiple Particle

Perturbations in airway mucus properties contribute to lung function decline in patients with chronic obstructive pulmonary disease (COPD). While alterations in bulk mucus rheology have been widely explored, microscopic mucus properties that directly impact on the dynamics of microorganisms and immune cells in the COPD lungs are yet to be investigated.We hypothesised that a tightened mesh structure of spontaneously expectorated mucus (i.e. sputum) would contribute to increased COPD disease severity. Here, we investigated whether the mesh size of COPD sputum, quantified by muco-inert nanoparticle (MIP) diffusion, correlated with sputum composition and lung function measurements.The microstructure of COPD sputum was assessed based on the mean squared displacement (MSD) of variously sized MIPs measured by multiple particle tracking. MSD values were correlated with sputum composition and spirometry. In total, 33 samples collected from COPD or non-COPD individuals were analysed.We found that 100 nm MIPs differentiated microstructural features of COPD sputum. The mobility of MIPs was more hindered in sputum samples from patients with severe COPD, suggesting a tighter mucus mesh size. Specifically, MSD values inversely correlated with lung function.These findings suggest that sputum microstructure may serve as a novel risk factor for COPD progression and severity.

Download Full-text

Impedância pulmonar como novo marcador de fisioterapia respiratória em adultos com distúrbios ventilatórios obstrutivos

Medicina (Ribeirao Preto Online) ◽

10.11606/issn.2176-7262.v52i4p319-327 ◽

2019 ◽

Vol 52 (4) ◽

pp. 319-327

Author(s):

Dyovana Silva Dos Santos ◽

Andressa Schenkel Spitznagel ◽

Karolini Reis Branco ◽

Márcio Vinícius Fagundes Donadio ◽

Camila Isabel Santos Schivinski ◽

...

Keyword(s):

Chronic Obstructive Pulmonary Disease ◽

Cystic Fibrosis ◽

Physical Therapy ◽

Pulmonary Disease ◽

Airway Resistance ◽

Forced Oscillation ◽

Chronic Obstructive ◽

Impulse Oscillometry ◽

Obstructive Pulmonary Disease ◽

Bronchial Diseases

Modelo do estudo: Revisão sistemática. Objetivo: Avaliar se os recursos de fisioterapia respiratória modificam a impedância pulmonar avaliada pelas técnicas de oscilações forçadas (TOF’s) em adultos com distúrbios ventilatórios obstrutivos. Método: Trata-se de uma revisão sistemática conduzida nas bases de dados PubMed, Scielo, Lilacs e PEDro, utilizando-se a seguinte estratégia de busca: Obstructive pulmonary disease OR chronic obstructive pulmonary disease OR COPD OR Bronchiectasis OR Bronchial diseases OR Cystic fibrosis OR mucoviscidosis AND impulse oscillometry OR forced oscillation techniques AND physical therapy OR physiotherapy AND Airway Resistance. Resultados: De um total de 216 artigos, apenas 3 foram incluídos. As amostras totalizaram 64 participantes, incluindo adultos com fibrose cística (FC), doença pulmonar obstrutiva crônica (DPOC) e bronquiectasias. Dois estudos utilizaram o flutter® e um realizou drenagem autógena. A impedância pulmonar foi avaliada em duas pesquisas pelo sistema de oscilometria de impulso (IOS) e em um pela TOF modificada (TOF-m). Houve redução da resistência em várias frequências, sendo que as mais frequentes foram a resistência total (3/3), a resistência central (2/3) e a periférica (2/3). Além disso, a reatância pulmonar apresentou resultados conflitantes. Conclusão: Evidenciou-se que os recursos fisioterapêuticos utilizados para remoção de secreções das vias aéreas modificam a impedância pulmonar avaliada pelas TOF’s em adultos com DVO, sendo a resistência total das vias aéreas o parâmetro com maior ganho terapêutico.

Download Full-text

Oral and Oropharyngeal Sensory Function in Adults With Chronic Obstructive Pulmonary Disease

American Journal of Speech-Language Pathology ◽

10.1044/2019_ajslp-19-00095 ◽

2020 ◽

Vol 29 (2) ◽

pp. 864-872

Author(s):

Fernanda Borowsky da Rosa ◽

Adriane Schmidt Pasqualoto ◽

Catriona M. Steele ◽

Renata Mancopes

Keyword(s):

Chronic Obstructive Pulmonary Disease ◽

Oral Cavity ◽

Pulmonary Disease ◽

Thermal Sensation ◽

Sensory Function ◽

Control Group ◽

Chronic Obstructive ◽

Obstructive Pulmonary Disease ◽

Age Related ◽

Copd Patients

Introduction The oral cavity and pharynx have a rich sensory system composed of specialized receptors. The integrity of oropharyngeal sensation is thought to be fundamental for safe and efficient swallowing. Chronic obstructive pulmonary disease (COPD) patients are at risk for oropharyngeal sensory impairment due to frequent use of inhaled medications and comorbidities including gastroesophageal reflux disease. Objective This study aimed to describe and compare oral and oropharyngeal sensory function measured using noninstrumental clinical methods in adults with COPD and healthy controls. Method Participants included 27 adults (18 men, nine women) with a diagnosis of COPD and a mean age of 66.56 years ( SD = 8.68). The control group comprised 11 healthy adults (five men, six women) with a mean age of 60.09 years ( SD = 11.57). Spirometry measures confirmed reduced functional expiratory volumes (% predicted) in the COPD patients compared to the control participants. All participants completed a case history interview and underwent clinical evaluation of oral and oropharyngeal sensation by a speech-language pathologist. The sensory evaluation explored the detection of tactile and temperature stimuli delivered by cotton swab to six locations in the oral cavity and two in the oropharynx as well as identification of the taste of stimuli administered in 5-ml boluses to the mouth. Analyses explored the frequencies of accurate responses regarding stimulus location, temperature and taste between groups, and between age groups (“≤ 65 years” and “> 65 years”) within the COPD cohort. Results We found significantly higher frequencies of reported use of inhaled medications ( p < .001) and xerostomia ( p = .003) in the COPD cohort. Oral cavity thermal sensation ( p = .009) was reduced in the COPD participants, and a significant age-related decline in gustatory sensation was found in the COPD group ( p = .018). Conclusion This study found that most of the measures of oral and oropharyngeal sensation remained intact in the COPD group. Oral thermal sensation was impaired in individuals with COPD, and reduced gustatory sensation was observed in the older COPD participants. Possible links between these results and the use of inhaled medication by individuals with COPD are discussed.

Download Full-text