Mucus Clearance in Simulated Trachea by Repeated Pulses and Airflow Oscillations

We investigated the effects of high-frequency chest wall compression (HFCWC) on peripheral and tracheal mucus clearance in anesthetized spontaneously breathing dogs. HFCWC was achieved by oscillating the pressure in a thoracic cuff with a piston pump. Regional lung retention of a technetium-99m sulfur colloid aerosol was monitored with a gamma camera. A peripheral mucus clearance index (PMCI) was defined for each region of interest. The tracheal mucus clearance rate (TMCR) was determined by bronchoscopic visualization of marker particle transport. Phase I: In seven dogs, 30 min of HFCWC at 13 Hz with peak cuff pressure (Pcuff) 100–120 cmH2O was found to significantly enhance PMCI in regions immediately under the cuff. (delta PMCI = 24.4 +/- 4.6 in the basal peripheral region.) Phase II: Because of subpleural hemorrhage in phase I, the effect of HFCWC on TMCR at various Pcuff levels was studied in five dogs. The enhancement of TMCR by HFCWC reached a plateau level at Pcuff = 50 cmH2O. Phase III: HFCWC at 13 Hz with Pcuff = 50–60 cmH2O was found to significantly enhance PMCI in five dogs without the consequence of hemorrhage. Correlations were found between the enhancement of PMCI and TMCR by HFCWC. These results demonstrate that HFCWC is effective in enhancing both peripheral and central mucus clearance in dogs and safe when moderate pressures are applied.

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Aerosol Medications for Treatment of Mucus Clearance Disorders

Respiratory Care ◽

10.4187/respcare.04087 ◽

2015 ◽

Vol 60 (6) ◽

pp. 825-832 ◽

Cited By ~ 19

Author(s):

B. K. Rubin

Keyword(s):

Mucus Clearance

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Clinical and Genetic Analysis of Children with Kartagener Syndrome

Cells ◽

10.3390/cells8080900 ◽

2019 ◽

Vol 8 (8) ◽

pp. 900 ◽

Cited By ~ 6

Author(s):

Rute Pereira ◽

Telma Barbosa ◽

Luís Gales ◽

Elsa Oliveira ◽

Rosário Santos ◽

...

Keyword(s):

Autosomal Recessive Disorder ◽

Kartagener Syndrome ◽

Mucus Clearance ◽

Pathogenic Variants ◽

Transmission Electron ◽

Whole Exome ◽

Dynein Arms ◽

Organ Laterality ◽

Ciliary Dyskinesia ◽

Laterality Defects

Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disorder characterized by dysfunction of motile cilia causing ineffective mucus clearance and organ laterality defects. In this study, two unrelated Portuguese children with strong PCD suspicion underwent extensive clinical and genetic assessments by whole-exome sequencing (WES), as well as ultrastructural analysis of cilia by transmission electron microscopy (TEM) to identify their genetic etiology. These analyses confirmed the diagnostic of Kartagener syndrome (KS) (PCD with situs inversus). Patient-1 showed a predominance of the absence of the inner dynein arms with two disease-causing variants in the CCDC40 gene. Patient-2 showed the absence of both dynein arms and WES disclosed two novel high impact variants in the DNAH5 gene and two missense variants in the DNAH7 gene, all possibly deleterious. Moreover, in Patient-2, functional data revealed a reduction of gene expression and protein mislocalization in both genes’ products. Our work calls the researcher’s attention to the complexity of the PCD and to the possibility of gene interactions modelling the PCD phenotype. Further, it is demonstrated that even for well-known PCD genes, novel pathogenic variants could have importance for a PCD/KS diagnosis, reinforcing the difficulty of providing genetic counselling and prenatal diagnosis to families.

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Effects of exercise and airway clearance (positive expiratory pressure) on mucus clearance in cystic fibrosis: a randomised crossover trial

European Respiratory Journal ◽

10.1183/13993003.01793-2018 ◽

2019 ◽

Vol 53 (4) ◽

pp. 1801793 ◽

Cited By ~ 6

Author(s):

Tiffany J. Dwyer ◽

Evangelia Daviskas ◽

Rahizan Zainuldin ◽

Jordan Verschuer ◽

Stefan Eberl ◽

...

Keyword(s):

Cystic Fibrosis ◽

Lung Disease ◽

Crossover Trial ◽

Treadmill Exercise ◽

Forced Expiratory Volume ◽

Mean Difference ◽

Peak Oxygen Consumption ◽

Mucus Clearance ◽

Airway Clearance ◽

Positive Expiratory Pressure

Exercise improves mucus clearance in people without lung disease and those with chronic bronchitis. No study has investigated exercise alone for mucus clearance in cystic fibrosis (CF). The aim of this study was to compare the effects of treadmill exercise to resting breathing and airway clearance with positive expiratory pressure (PEP) therapy on mucus clearance in adults with CF.This 3-day randomised, controlled, crossover trial included 14 adults with mild to severe CF lung disease (forced expiratory volume in 1 s % predicted 31–113%). Interventions were 20 min of resting breathing (control), treadmill exercise at 60% of the participant's peak oxygen consumption or PEP therapy (including huffing and coughing). Mucus clearance was measured using the radioaerosol technique and gamma camera imaging.Treadmill exercise improved whole lung mucus clearance compared to resting breathing (mean difference 3%, 95% CI 2–4); however, exercise alone was less effective than PEP therapy (mean difference −7%, 95% CI −6– −8). When comparing treadmill exercise to PEP therapy, there were no significant differences in mucus clearance from the intermediate and peripheral lung regions, but significantly less clearance from the central lung region (likely reflecting the huffing and coughing that was only in PEP therapy).It is recommended that huffing and coughing are included to maximise mucus clearance with exercise.

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Comparison of Head-Down Tilt versus Flat Position on Mucus Clearance and Respiratory Mechanics in Mechanically Ventilated Patients: A Randomized Crossover Trial

Critical Reviews in Physical and Rehabilitation Medicine ◽

10.1615/physmedrehabil.2020032980 ◽

2020 ◽

Vol 32 (1) ◽

pp. 23-38

Author(s):

Siri Shetty ◽

Gopala Krishna Alaparthi ◽

Shyam Krishnan K ◽

Madhusudan Upadya ◽

Ashish Prabhakar ◽

...

Keyword(s):

Crossover Trial ◽

Respiratory Mechanics ◽

Mechanically Ventilated ◽

Mechanically Ventilated Patients ◽

Mucus Clearance ◽

Randomized Crossover Trial ◽

Ventilated Patients

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982: AIRWAY PRESSURE RELEASE VENTILATION ACCELERATES MUCUS CLEARANCE VIA INCREASED EXPIRATORY FLOW RATE

Critical Care Medicine ◽

10.1097/01.ccm.0000509658.82538.7f ◽

2016 ◽

Vol 44 (12) ◽

pp. 321-321

Author(s):

Melissa Mahajan ◽

David DiStefano ◽

Josh Satalin ◽

Penny Andrews ◽

Sumeet Jain ◽

...

Keyword(s):

Flow Rate ◽

Airway Pressure ◽

Airway Pressure Release Ventilation ◽

Pressure Release ◽

Mucus Clearance ◽

Expiratory Flow ◽

Pressure Release Ventilation

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Altered Sinonasal Ciliary Dynamics in Chronic Rhinosinusitis

American Journal of Rhinology ◽

10.2500/ajr.2006.20.2870 ◽

2006 ◽

Vol 20 (3) ◽

pp. 325-329 ◽

Cited By ~ 62

Author(s):

Bei Chen ◽

Jeffrey Shaari ◽

Steven Eau Claire ◽

James N. Palmer ◽

Alexander G. Chiu ◽

...

Keyword(s):

Chronic Rhinosinusitis ◽

Adenosine Triphosphate ◽

High Speed ◽

Beat Frequency ◽

Ciliary Beat Frequency ◽

Ciliary Activity ◽

Differential Interference Contrast Microscopy ◽

Dynamic Regulation ◽

Mucus Clearance ◽

Persistent Inflammation

Background Although multiple etiologies contribute to the development of rhinosinusitis, a common pathophysiological sequelae is ineffective sinonasal mucociliary clearance, resulting in stasis of sinonasal secretions, with subsequent infection, and persistent inflammation. The respiratory cilia beat continually at a basal rate, while during times of stress, such as exercise or infection, ciliary beat frequency (CBF) increases, accelerating mucus clearance. Previous investigations have led to conflicting results with some authors reporting decreased CBF while others have found normal values of CBF in patients with chronic rhinosinusitis (CRS). Additionally, these studies have only analyzed basal CBF. The goal of this study was to compare the basal as well as the stimulated sinonasal CBF in patients with CRS versus controls. Methods A dual temperature controlled perfusion chamber, differential interference contrast microscopy, and high-speed digital video were used to analyze both basal and adenosine triphosphate (100 μM)–stimulated CBF in human sinonasal mucosal explants. Results Although no difference in basal CBF was detected between control and CRS patients, a marked difference in stimulated CBF was noted. Exogenously applied adenosine triphosphate resulted in a 50–70% increase of CBF in control tissue with a minimally observed CBF increase in explants from CRS patients. Conclusion Dynamic regulation of respiratory ciliary activity is critical for the respiratory epithelium to adapt to varying environmental situations. Thus, diminished or absent adaptation could predispose the sinonasal cavity to accumulation of inhaled infectious and noxious particulate matter resulting in infection/inflammation. Our findings suggest that CRS patients have decreased sinonasal ciliary adaptation to environmental stimuli.

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