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Lower airway bronchoscopic interpretation
Published in Don Hayes, Kara D. Meister, Pediatric Bronchoscopy for Clinicians, 2023
Kimberley R. Kaspy, Sara M. Zak
Mucus plugging is a common problem in children. Particularly in smaller airways, thick and sticky mucus can lead to airway obstruction with impaired mucociliary clearance and becomes difficult to remove.Whereas this more commonly occurs in segmental bronchi, it can be seen in lobar or mainstem bronchi.Mucus plugging can be secondary to an infection or related to underlying impairments in mucociliary clearance. Lack of humidification of patients, who are intubated or who have a tracheostomy, can also lead to drying of mucus and resultant plugging.In some instances, mucus plugs cannot be removed despite direct visualization and suctioning through the flexible bronchoscope. Chapters 8 and 9 describe additional interventions and techniques that may be used.
Rhinosinusitis and Lacrimal Disorders
Published in R James A England, Eamon Shamil, Rajeev Mathew, Manohar Bance, Pavol Surda, Jemy Jose, Omar Hilmi, Adam J Donne, Scott-Brown's Essential Otorhinolaryngology, 2022
Tobacco smoke exposure inhibits mucociliary clearance and epithelial regeneration. Those exposed to passive smoking present with more severe disease and higher rates of revision surgery.
Airway Repair and Adaptation to Inhalation Injury
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
S. F. Paul Man, William C. Hulbert
Mucociliary clearance is a complex process that depends on many variables, which can be grouped into ciliary and mucous factors. Among the ciliary factors are frequency and amplitude of the ciliary beating stroke, the generation of co-ordinated metachronal waves, the length of cilia, and the number of ciliated cells per unit of airway surface. In this regard, although no evidence for direct nervous control of ciliary function has been demonstrated, β-adrenergic agonists and digoxin have been demonstrated to enhance ciliary function (Verdugo et al., 1980; Wanner, 1977). Among the mucous factors are the nature of the periciliary fluid and its depth, and the viscoelastic properties of the mucus.
Effects of hepatocyte growth factor-transfected mesenchymal stem cell transplantation in canine injured vocal folds
Published in Growth Factors, 2023
Xingqiao Xie, Xumao Li, Xinsheng Lin, Xiangyu Chen, Chenshan Zhang, Guangbin Sun
The VFs are continually exposed to inhaled pathogens, toxins, and foreign particles. Mucociliary clearance is an essential part of the defense system, which relies on appropriate interactions between the ciliated epithelium, the height of the periciliary fluid, and mucus. Mucus traps inhaled pathogens and particles, while cilia move both the mucus layer and fluid in the underlying periciliary layer (Kahwa, Balemba, and Assey 2000; Stannard and O'Callaghan 2006). Scanning electron microscopy revealed that the HGF-transfected ADSCs group had fewer microvilli with a slightly sparse distribution than normal VFs, whereas these negative changes were more severe in other groups. Densely packed and extensively distributed microvilli can protect VFs from foreign factors, participating in VF repair.
CT imaging features of paranasal sinuses in children with primary ciliary dyskinesia
Published in Acta Oto-Laryngologica, 2022
Huiying Lyu, Zhuoyao Guo, Chao Chen, Bo Duan, Zhengmin Xu, Wenxia Chen
Primary ciliary dyskinesia (PCD) is primarily an autosomal recessive genetic disease characterized by abnormalities in ciliary structure and/or function [1]. PCD leads to impaired mucociliary clearance and a wide variety of symptoms primarily affecting the respiratory system. Clinical features include recurrent infections of the upper and lower respiratory tract, chronic rhinosinusitis (CRS), otitis media with effusion, bronchiectasis, dextrocardia/situs inversus, infertility, ectopic pregnancy, etc. [2]. The prevalence of this disease in the general population is estimated to be one in 15,000–20,000 [3]. The symptoms of PCD (cough, recurrent bronchial infections) are non-specific compared to other causes of lower respiratory tract infection, therefore, PCD is significantly underdiagnosed. The true prevalence could be even higher.
Health impact of e-cigarettes and heated tobacco products in chronic obstructive pulmonary disease: current and emerging evidence
Published in Expert Review of Respiratory Medicine, 2022
Jaymin B. Morjaria, Davide Campagna, Grazia Caci, Renee O’Leary, Riccardo Polosa
It is not surprising to observe harm reversal with combustion-free nicotine delivery technologies. For example, restoration of lung defense has been shown in daily solos EC and HTP users [113]. A study has found that smokers who had switched to combustion-free nicotine delivery technologies (i.e. ECs and HTPs) exhibited mucociliary clearance efficiency similar to that of never and former smokers [113]. This means that smokers who have switched away from combustible cigarettes regain an important protection against lung infections and inflammation. In turn, this decreases the risk of infection and provides an additional explanation for the significant reduction in respiratory exacerbations observed in patients with COPD who ceased or markedly reduced their tobacco consumption after switching to ECs or HTPs [104,110]. The fact that stopping smoking (including by substituting tobacco cigarettes with non-combustible sources of nicotine) would produce substantial improvement in mucociliary clearance is a significant finding, but it is not unexpected. Under normal conditions of use, the level of cilia-toxic chemicals in EC and HTP aerosol emissions are 80–99% lower compared to cigarette smoke [26,27,34,35,80]. Accordingly, exposure to aerosols generated from combustion-free nicotine delivery technologies is expected to have a much less disruptive impact on the functional elements and self-repair characteristics of mucociliary defense system. This conclusion is consistent with what we have learnt about tobacco smoke chemical composition and COPD pathogenesis over the last 40–50 years.