1
|
Gannot N, Li X, Phillips CD, Ozel AB, Uchima Koecklin KH, Lloyd JP, Zhang L, Emery K, Stern T, Li JZ, Li P. A vagal-brainstem interoceptive circuit for cough-like defensive behaviors in mice. Nat Neurosci 2024; 27:1734-1744. [PMID: 38977887 PMCID: PMC11374482 DOI: 10.1038/s41593-024-01712-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 06/18/2024] [Indexed: 07/10/2024]
Abstract
Coughing is a respiratory behavior that plays a crucial role in protecting the respiratory system. Here we show that the nucleus of the solitary tract (NTS) in mice contains heterogenous neuronal populations that differentially control breathing. Within these subtypes, activation of tachykinin 1 (Tac1)-expressing neurons triggers specific respiratory behaviors that, as revealed by our detailed characterization, are cough-like behaviors. Chemogenetic silencing or genetic ablation of Tac1 neurons inhibits cough-like behaviors induced by tussive challenges. These Tac1 neurons receive synaptic inputs from the bronchopulmonary chemosensory and mechanosensory neurons in the vagal ganglion and coordinate medullary regions to control distinct aspects of cough-like defensive behaviors. We propose that these Tac1 neurons in the NTS are a key component of the airway-vagal-brain neural circuit that controls cough-like defensive behaviors in mice and that they coordinate the downstream modular circuits to elicit the sequential motor pattern of forceful expiratory responses.
Collapse
Affiliation(s)
- Noam Gannot
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Xingyu Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | | | - Ayse Bilge Ozel
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | | | - John P Lloyd
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | - Lusi Zhang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Katie Emery
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Tomer Stern
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Jun Z Li
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | - Peng Li
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
2
|
Sundar KM, Stark A, Morris MJ. Laryngeal Dysfunction Manifesting as Chronic Refractory Cough and Dyspnea: Laryngeal Physiology in Respiratory Health and Disease. Chest 2024; 166:171-186. [PMID: 38508333 DOI: 10.1016/j.chest.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/10/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024] Open
Abstract
TOPIC IMPORTANCE Laryngeal dysfunction as a cause of chronic refractory cough and episodic dyspnea is often missed, which results in unnecessary testing and delays in diagnosis. Understanding laryngeal roles in breathing and airway protection can help to appreciate the propensity to laryngeal dysfunction with aging, chronic lung disease, and sleep apnea. REVIEW FINDINGS The human larynx is a complex muscular structure that is responsible for multiple roles of breathing, vocalization, coughing, and swallowing. To undertake these activities, the larynx has a high density of sensory and motor innervation. In addition to common embryological origins with the pharynx and esophagus, with which many laryngeal activities are shared, somatomotor and autonomic pathways regulate emotional, cognitive, and complex motor sequence-planning activities within the larynx. Due to its unique location, the larynx is susceptible to infectious and gastroesophageal reflux-related insults. Couple this with key roles in regulation of airflow and mediation of airway protective reflexes, it is not surprising that neuropathic abnormalities and muscle dysfunction frequently develop. The expression of laryngeal dysfunction as hypersensitivity to mechanical, thermal, chemical, and other stimuli leads to exaggerated airway protective reflexes (laryngeal adductor reflex and cough reflex) manifesting as dyspnea and cough. SUMMARY Pulmonologists should incorporate assessment of laryngeal dysfunction during evaluation of chronic refractory cough and dyspnea. Recognition of laryngeal hypersensitivity in the patient with chronic refractory cough can identify patients who may benefit from cough suppression therapies. Similarly, timely identification of inducible laryngeal obstruction may not only resolve episodic dyspnea but lessen the need for unnecessary testing and treatments.
Collapse
Affiliation(s)
- Krishna M Sundar
- Division of Pulmonary and Critical Care Medicine, University of Utah, Salt Lake City, UT.
| | - Amanda Stark
- Department of Otolaryngology-Head & Neck Surgery & Voice Disorders Center, University of Utah, Salt Lake City, UT
| | - Michael J Morris
- Pulmonary & Critical Care Service, Brooke Army Medical Center, JBSA Fort Sam Houston, TX
| |
Collapse
|
3
|
Sundar KM, Stark AC, Dicpinigaitis P. Chronic Cough and Obstructive Sleep Apnea. Sleep Med Clin 2024; 19:239-251. [PMID: 38692749 DOI: 10.1016/j.jsmc.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Chronic cough, defined as a cough lasting more than 8 weeks, is a common medical condition occurring in 5% to 10% of the population. Its overlap with another highly prevalent disorder, obstructive sleep apnea (OSA), is therefore not surprising. The relationship between chronic cough and OSA extends beyond this overlap with higher prevalence of OSA in patients with chronic cough than in the general population. The use of continuous positive airway pressure can result in improvement in chronic cough although further studies are needed to understand which patients will experience benefit in their cough from the treatment of comorbid OSA.
Collapse
Affiliation(s)
- Krishna M Sundar
- Division of Pulmonary & Critical Care Medicine, 30 N, Mario Capecchi Drive, 2nd floor North, University of Utah, Salt Lake City, UT 84112, USA.
| | - Amanda Carole Stark
- Voice Disorders Center, University of Utah, 729 Arapeen Drive, Salt Lake City, UT 84106, USA
| | - Peter Dicpinigaitis
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, 1825 Eastchester Road, Bronx, NY 10461, USA
| |
Collapse
|
4
|
Hegde S, Sreeram S, Alter IL, Shor C, Valdez TA, Meister KD, Rameau A. Cough Sounds in Screening and Diagnostics: A Scoping Review. Laryngoscope 2024; 134:1023-1031. [PMID: 37672667 PMCID: PMC10915103 DOI: 10.1002/lary.31042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/04/2023] [Accepted: 08/29/2023] [Indexed: 09/08/2023]
Abstract
OBJECTIVE The aim of the study was to examine applications of cough sounds towards screening tools and diagnostics in the biomedical and engineering literature, with particular focus on disease types, acoustic data collection protocols, data processing and analytics, accuracy, and limitations. DATA SOURCES PubMed, EMBASE, Web of Science, Scopus, Cochrane Library, IEEE Xplore, Engineering Village, and ACM Digital Library were searched from inception to August 2021. REVIEW METHODS A scoping review was conducted on screening and diagnostic uses of cough sounds in adults, children, and animals, in English peer-reviewed and gray literature of any design. RESULTS From a total of 438 abstracts screened, 108 articles met inclusion criteria. Human studies were most common (77.8%); the majority focused on adults (57.3%). Single-modality acoustic data collection was most common (71.2%), with few multimodal studies, including plethysmography (15.7%) and clinico-demographic data (7.4%). Data analytics methods were highly variable, with 61.1% using machine learning, the majority of which (78.8%) were published after 2010. Studies commonly focused on cough detection (41.7%) and screening of COVID-19 (11.1%); among pediatric studies, the most common focus was diagnosis of asthma (52.6%). CONCLUSION Though the use of cough sounds in diagnostics is not new, academic interest has accelerated in the past decade. Cough sound offers the possibility of an accessible, noninvasive, and low-cost disease biomarker, particularly in the era of rapid development of machine learning capabilities in combination with the ubiquity of cellular technology with high-quality recording capability. However, most cough sound literature hinges on nonstandardized data collection protocols and small, nondiverse, single-modality datasets, with limited external validity. Laryngoscope, 134:1023-1031, 2024.
Collapse
Affiliation(s)
- Siddhi Hegde
- KVG Medical College and Hospital, Sullia, Karnataka, India
| | - Shreya Sreeram
- KVG Medical College and Hospital, Sullia, Karnataka, India
| | - Isaac L. Alter
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, U.S.A
| | - Chaya Shor
- Weill Cornell Medicine, Sean Parker Institute for the Voice, New York, NY, U.S.A
| | - Tulio A. Valdez
- Division of Pediatric Otolaryngology, Otolaryngology--Head & Neck Surgery, Stanford University, Stanford, California, U.S.A
| | - Kara D. Meister
- Division of Pediatric Otolaryngology, Otolaryngology--Head & Neck Surgery, Stanford University, Stanford, California, U.S.A
| | - Anaïs Rameau
- Weill Cornell Medicine, Sean Parker Institute for the Voice, New York, NY, U.S.A
| |
Collapse
|
5
|
Núñez C, Chiatti MC, Tansella F, Coronel-Rodríguez C, Risco E. Efficacy and tolerability of SEDIFLÙ in treating dry or productive cough in the pediatric population (SEPEDIA): A pilot, randomized, double-blind, placebo-controlled, multicenter clinical trial. Clin Pediatr (Phila) 2024:99228241228074. [PMID: 38323572 DOI: 10.1177/00099228241228074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
The aim of this trial was to assess the effectiveness of Sediflù, a medical device containing active herbal ingredients, on nocturnal and diurnal persistent coughs in children, with a duration of 3 to 7 days. Children with a dry and/or productive cough were enrolled in this prospective, interventional, multicenter, placebo-controlled, double-blind, randomized clinical study. Clinical efficacy was assessed through the evaluation of the soothing action of Sediflù against dry and/or productive coughing, both at night and during the day, and other effects of coughing associated with quality of sleep: frequency, child's quality of sleep, parental quality of sleep and severity. Treatment with Sediflù improved both night-time and day-time cough scores from day 2. The diurnal score also improved significantly in the Sediflù group at days 3 and 7. Sediflù syrup can be considered a valid treatment for cough management in younger children with upper respiratory tract infections, shortening the cough duration.
Collapse
Affiliation(s)
- Carlos Núñez
- Pediatría Dr. Carlos Núñez de Prado Aparicio, Madrid, Spain
| | | | - Francesco Tansella
- Pediatric Infectious Diseases, Giovanni XXIII Children's Hospital, Bari, Italy
| | - Cristóbal Coronel-Rodríguez
- Centro de Salud Amante Laffón, Distrito de Atención Primaria Sevilla, Servicio Andaluz de Salud, Sevilla, Spain
| | - Ester Risco
- Unitat de Farmacologia, Farmacognòsia i Terapèutica, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| |
Collapse
|
6
|
Sugi T, Inubushi T, Ohno T, Onishi Y, Isobe T, Shigematsu T, Hanai S, Okada Y, Takahashi R, Tawara Y, Suzuki C, Kanno T, Magata Y, Fujishima I, Yoshikawa E, Ouchi Y. Neural substrates of cough control during coughing. Sci Rep 2024; 14:758. [PMID: 38191647 PMCID: PMC10774348 DOI: 10.1038/s41598-024-51477-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 01/05/2024] [Indexed: 01/10/2024] Open
Abstract
Cough is known as a protective reflex to keep the airway free from harmful substances. Although brain activity during cough was previously examined mainly by functional magnetic resonance imaging (fMRI) with model analysis, this method does not capture real brain activity during cough. To obtain accurate measurements of brain activity during cough, we conducted whole-brain scans during different coughing tasks while correcting for head motion using a restraint-free positron emission tomography (PET) system. Twenty-four healthy right-handed males underwent multiple PET scans with [15O]H2O. Four tasks were performed during scans: "resting"; "voluntary cough (VC)", which simply repeated spontaneous coughing; "induced cough (IC)", where participants coughed in response to an acid stimulus in the cough-inducing method with tartaric acid (CiTA); and "suppressed cough (SC)", where coughing was suppressed against CiTA. The whole brain analyses of motion-corrected data revealed that VC chiefly activated the cerebellum extending to pons. In contrast, CiTA-related tasks (IC and SC) activated the higher sensory regions of the cerebral cortex and associated brain regions. The present results suggest that brain activity during simple cough is controlled chiefly by infratentorial areas, whereas manipulating cough predominantly requires the higher sensory brain regions to allow top-down control of information from the periphery.
Collapse
Affiliation(s)
- Takafumi Sugi
- Department of Biofunctional Imaging, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
- Department of Rehabilitation Medicine, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Tomoo Inubushi
- Central Research Laboratory, Hamamatsu Photonics K.K., 5000, Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka, 434-8601, Japan
| | - Tomohisa Ohno
- Department of Dentistry, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Yuya Onishi
- Central Research Laboratory, Hamamatsu Photonics K.K., 5000, Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka, 434-8601, Japan
| | - Takashi Isobe
- Central Research Laboratory, Hamamatsu Photonics K.K., 5000, Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka, 434-8601, Japan
| | - Takashi Shigematsu
- Department of Rehabilitation Medicine, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Satoshi Hanai
- Department of Rehabilitation, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Yoshiro Okada
- Department of Rehabilitation, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Ryosuke Takahashi
- Department of Rehabilitation, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Yuichi Tawara
- School of Rehabilitation Sciences, Seirei Christopher University, 3453, Mikatahara, Kita-ku, Hamamatsu, Shizuoka, 433-8105, Japan
| | - Chie Suzuki
- Department of Molecular Imaging, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
| | - Toshihiko Kanno
- Hamamatsu Medical Imaging Center, Hamamatsu Medical Photonics Foundation, Shizuoka, 434-0041, Japan
| | - Yasuhiro Magata
- Department of Molecular Imaging, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan
| | - Ichiro Fujishima
- Department of Rehabilitation Medicine, Hamamatsu City Rehabilitation Hospital, 1-6-1 Wagokita, Naka-ku, Hamamatsu, Shizuoka, 433-8511, Japan
| | - Etsuji Yoshikawa
- Central Research Laboratory, Hamamatsu Photonics K.K., 5000, Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka, 434-8601, Japan
| | - Yasuomi Ouchi
- Department of Biofunctional Imaging, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu, Shizuoka, 431-3192, Japan.
- Hamamatsu Medical Imaging Center, Hamamatsu Medical Photonics Foundation, Shizuoka, 434-0041, Japan.
| |
Collapse
|
7
|
Mootassim-Billah S, Schoentgen J, De Bodt M, Roper N, Digonnet A, Le Tensorer M, Van Nuffelen G, Van Gestel D. Acoustic Analysis of Voluntary Coughs, Throat Clearings, and Induced Reflexive Coughs in a Healthy Population. Dysphagia 2023; 38:1467-1486. [PMID: 37245187 PMCID: PMC10225042 DOI: 10.1007/s00455-023-10574-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 03/31/2023] [Indexed: 05/29/2023]
Abstract
Cough efficacy is considered a reliable predictor of the aspiration risk in head and neck cancer patients with radiation-associated dysphagia. Currently, coughing is assessed perceptually or aerodynamically. The goal of our research is to develop methods of acoustic cough analysis. In this study, we examined in a healthy population the acoustical differences between three protective maneuvers: voluntary cough, voluntary throat clearing, and induced reflexive cough. Forty healthy participants were included in this study. Voluntary cough, voluntary throat clearing, and reflexive cough samples were recorded and analyzed acoustically. Temporal acoustic features were the following: the slope and curvature of the amplitude contour, as well as the average, slope, and curvature of the sample entropy and kurtosis contours of the recorded signal. Spectral features were the relative energy in the frequency bands (0-400 Hz, 400-800 Hz, 800-1600 Hz, 1600 Hz-3200 Hz, > 3200 Hz) as well as the weighted spectral energy. Results showed that, compared to a voluntary cough, a throat clearing starts with a weaker onset pulse and involves oscillations from the onset to the offset (concave curvature of the amplitude contour, p < 0.05), lower average (p < 0.05), and slope (p < 0.05) as well as lower convex curvature (p < 0.05) of the kurtosis contour. An induced reflexive cough starts with a higher and briefer onset burst and includes higher frication noise (larger convexity of the curvature of the amplitude and kurtosis contours (p < 0.05)) compared to a voluntary cough. The conclusion is that voluntary coughs are acoustically significantly different from voluntary throat clearings and induced reflexive coughs.
Collapse
Affiliation(s)
- Sofiana Mootassim-Billah
- Department of Radiation Oncology, Speech Therapy, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium.
| | - Jean Schoentgen
- Department of Biomechatronics, Université Libre de Bruxelles, Brussels, Belgium
| | - Marc De Bodt
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
| | - Nicolas Roper
- Department of Oto-Rhino-Laryngology and Head & Neck Surgery, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Antoine Digonnet
- Department of Surgical Oncology, Head and Neck Surgery Unit, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium
| | - Mathilde Le Tensorer
- Speech Therapy Unit, Institut Jules Bordet, Hôpital Universitaire de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
| | - Gwen Van Nuffelen
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
| | - Dirk Van Gestel
- Department of Radiation Oncology, Head and Neck Unit, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium
| |
Collapse
|
8
|
Mootassim-Billah S, Van Nuffelen G, Schoentgen J, De Bodt M, Van Gestel D. Assessment of radio(chemo)therapy-related dysphagia in head and neck cancer patients based on cough-related acoustic features: a prospective phase II national clinical trial (ACCOUGH-P/A trial). Trials 2023; 24:619. [PMID: 37773172 PMCID: PMC10540417 DOI: 10.1186/s13063-023-07660-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/19/2023] [Indexed: 10/01/2023] Open
Abstract
BACKGROUND Radiation-associated dysphagia is defined as impaired swallowing efficiency/safety following (chemo)radiotherapy in head and neck cancer patients. In a dysphagia framework, impaired coughing may lead to lung aspiration and fatal lung infection. Although cough efficacy is a predictor of the risk of aspiration, cough investigation is minimal in patients with radiation-associated dysphagia. Because cough is a transient signal, existing software for speech analysis are not appropriate. The goal of our project is to develop an assessment method using acoustic features related to voluntary and reflexive coughs as biomarkers of the risk of penetration/aspiration in patients with radiation-associated dysphagia. METHODS Healthy subjects and head and neck cancer patients with and without dysphagia will produce voluntary coughs, throat clearings and reflexive coughs. Recordings will be made using an acoustic microphone and a throat microphone. The recorded signals will be manually segmented and subsequently analysed with a software under development. Automatic final segmentation enables to measure cough duration. The first method of analysis includes temporal features: the amplitude contour, the sample entropy and the kurtosis. These features report respectively the strength, the unpredictability (turbulence noise due to the air jet) and the impulsive quality (burst) of the signal. The second method of analysis consists of a spectral decomposition of the relative cough signal energy into several frequency bands (0-400 Hz, 400-800 Hz, 800-1600 Hz, 1600-3200 Hz, > 3200 Hz). The primary outcome of this exploratory research project is the identification of a set of descriptive acoustic cough features in healthy subjects as reference data (ACCOUGH). The secondary outcome of this research in head and neck cancer patients with radiation-associated dysphagia includes the identification of (1) a set of descriptive acoustic cough features as biomarkers of penetration-aspiration (ACCOUGH-P/A), (2) swallowing scores, (3) voice features and (4) aerodynamic cough features. DISCUSSION This study is expected to develop methods of acoustic cough analysis to enhance the assessment of radiation-associated dysphagia in head and neck cancer patients following (chemo)radiation. TRIAL REGISTRATION International Standard Randomized Controlled Trials Number (ISRCTN) registry ISRCTN16540497. Accepted on 23 June 2023.
Collapse
Affiliation(s)
- Sofiana Mootassim-Billah
- Department of Radiation Oncology, Speech Therapy, Institut Jules Bordet, Hôpital Universitaire de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium.
| | - Gwen Van Nuffelen
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
| | - Jean Schoentgen
- Department of Biomechatronics, Université Libre de Bruxelles, Brussels, Belgium
| | - Marc De Bodt
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication Disorders, Antwerp University Hospital, Antwerp, Belgium
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health Sciences, University of Ghent, Ghent, Belgium
| | - Dirk Van Gestel
- Department of Radiation Oncology, Head and Neck Unit, Institut Jules Bordet, Hôpital Universitaire de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
| |
Collapse
|
9
|
McClure EW, Daniels RN. Classics in Chemical Neuroscience: Dextromethorphan (DXM). ACS Chem Neurosci 2023. [PMID: 37290117 DOI: 10.1021/acschemneuro.3c00088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023] Open
Abstract
Dextromethorphan (DXM) was introduced in 1958 as the first non-opioid cough suppressant and is indicated for multiple psychiatric disorders. It has been the most used over-the-counter cough suppressant since its emergence. However, individuals quickly noticed an intoxicating and psychedelic effect if they ingested large doses. DXM's antagonism at N-methyl-d-aspartate receptors (NMDAr) is thought to underly its efficacy in treating acute cough, but supratherapeutic doses mimic the activity of dissociative hallucinogens, such as phencyclidine and ketamine. In this Review we will discuss DXM's synthesis, manufacturing information, drug metabolism, pharmacology, adverse effects, recreational use, abuse potential, and its history and importance in therapy to present DXM as a true classic in chemical neuroscience.
Collapse
Affiliation(s)
- Elliot W McClure
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy, Nashville, Tennessee 37204, United States
| | - R Nathan Daniels
- Department of Pharmaceutical Sciences, Union University College of Pharmacy, Jackson, Tennessee 38305, United States
| |
Collapse
|
10
|
Kim KH, Kim DH. Effects of Maitland Thoracic Joint Mobilization and Lumbar Stabilization Exercise on Diaphragm Thickness and Respiratory Function in Patients with a History of COVID-19. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph192417044. [PMID: 36554923 PMCID: PMC9779054 DOI: 10.3390/ijerph192417044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/01/2022] [Accepted: 12/16/2022] [Indexed: 06/01/2023]
Abstract
Objective: We investigated the effects of maitland thoracic joint mobilization and lumbar stabilization exercise on diaphragm thickness and respiratory function in patients with a history of COVID-19. Methods: Thirty patients who had passed one month after COVID-19 onset were randomly divided into maitland thoracic mobilization and lumbar stabilization and combined breathing exercise groups; each group performed thoracic mobilization and lumbar stabilization exercises and combined breathing exercise and ergometer exercises, respectively, for 50 min, three times a week, for eight weeks. We used the MYSONO U5 MicroQuark to evaluate diaphragm thickness and respiratory function (forced vital capacity, forced expiratory volume in the one second, peak expiratory flow), respectively. Results: There were no significant between-group differences in general patient characteristics and change in diaphragm thickness and respiratory function. Both groups showed significant improvement within each parameter. However, the maitland thoracic mobilization and lumbar stabilization group showed more significant improvements than did the combined breathing exercise group (p < 0.05). Conclusion: In this study, we confirmed the maitland thoracic joint mobilization and lumbar stabilization exercise on the diaphragm thickness and respiratory function in patients with a history of COVID-19.
Collapse
Affiliation(s)
- Kyung-hun Kim
- Department of Physical Therapy, Gimcheon University, 214, Daehak-ro, Gimcheon 39528, Republic of Korea
- Gimcheon Institute of Rehabilitation Science, Gimcheon University, Gimcheon 39528, Republic of Korea
| | - Dong-hoon Kim
- Department of Physical Therapy, Gimcheon University, 214, Daehak-ro, Gimcheon 39528, Republic of Korea
- Gimcheon Institute of Rehabilitation Science, Gimcheon University, Gimcheon 39528, Republic of Korea
| |
Collapse
|
11
|
de la Guerra PA, Corvera Poiré E. Pulsatile parallel flow of air and a viscoelastic fluid with multiple characteristic times. An application to mucus in the trachea and the frequency of cough. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:314003. [PMID: 35561687 DOI: 10.1088/1361-648x/ac6fa7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
We study the dynamics of a binary fluid, where the two fluids are flowing parallel to each other in a cylindrical geometry, and driven by a pulsatile pressure gradient. One of the fluids is a low viscosity Newtonian fluid, the other one is viscoelastic. In order to be able to apply the model to different biofluids, we consider that the viscoelastic fluid has several characteristic times. We characterize the dynamics of the fluids as generalized Darcy's laws, with linear response functions to pulsatile pressure gradients, whose parameters are coupled for both fluids through the fluid-fluid boundary conditions. We apply our results to the dynamics of mucus and air in the trachea and find that the frequency that allows for a larger movement of the mucus, coincides with the experimental frequency of cough. This allows us to propose a plausible explanation for the frequency of cough in healthy individuals, a mechanical process to expel noxious substances from the respiratory system.
Collapse
Affiliation(s)
- Pablo Alberto de la Guerra
- Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - E Corvera Poiré
- Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- UBICS Institute of Complex Systems, Universitat de Barcelona, Martí i Franquès 1, Barcelona 08028, Spain
| |
Collapse
|
12
|
Gregson FKA, Shrimpton AJ, Hamilton F, Cook TM, Reid JP, Pickering AE, Pournaras DJ, Bzdek BR, Brown J. Identification of the source events for aerosol generation during oesophago-gastro-duodenoscopy. Gut 2022; 71:871-878. [PMID: 34187844 PMCID: PMC8245282 DOI: 10.1136/gutjnl-2021-324588] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/16/2021] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To determine if oesophago-gastro-duodenoscopy (OGD) generates increased levels of aerosol in conscious patients and identify the source events. DESIGN A prospective, environmental aerosol monitoring study, undertaken in an ultraclean environment, on patients undergoing OGD. Sampling was performed 20 cm away from the patient's mouth using an optical particle sizer. Aerosol levels during OGD were compared with tidal breathing and voluntary coughs within subject. RESULTS Patients undergoing bariatric surgical assessment were recruited (mean body mass index 44 and mean age 40 years, n=15). A low background particle concentration in theatres (3 L-1) enabled detection of aerosol generation by tidal breathing (mean particle concentration 118 L-1). Aerosol recording during OGD showed an average particle number concentration of 595 L-1 with a wide range (3-4320 L-1). Bioaerosol-generating events, namely, coughing or burping, were common. Coughing was evoked in 60% of the endoscopies, with a greater peak concentration and a greater total number of sampled particles than the patient's reference voluntary coughs (11 710 vs 2320 L-1 and 780 vs 191 particles, n=9 and p=0.008). Endoscopies with coughs generated a higher level of aerosol than tidal breathing, whereas those without coughs were not different to the background. Burps also generated increased aerosol concentration, similar to those recorded during voluntary coughs. The insertion and removal of the endoscope were not aerosol generating unless a cough was triggered. CONCLUSION Coughing evoked during OGD is the main source of the increased aerosol levels, and therefore, OGD should be regarded as a procedure with high risk of producing respiratory aerosols. OGD should be conducted with airborne personal protective equipment and appropriate precautions in those patients who are at risk of having COVID-19 or other respiratory pathogens.
Collapse
Affiliation(s)
| | - Andrew J Shrimpton
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
- Department of Anaesthesia and Intensive Care Medicine, North Bristol NHS Trust, Bristol, UK
| | - Fergus Hamilton
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Tim M Cook
- Department of Anaesthesia and Intensive Care Medicine, Royal United Hospitals NHS Trust, Bath, and Bristol Medical School, University of Bristol, Bristol, UK
| | | | - Anthony E Pickering
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
- Bristol Anaesthesia, Pain and Critical Care Sciences, Translational Health Sciences, Bristol Medical School, Bristol, UK
| | - Dimitri J Pournaras
- Department of Upper Gastrointestinal and Bariatric/Metabolic Surgery, North Bristol NHS Trust, Bristol, UK
| | - Bryan R Bzdek
- School of Chemistry, University of Bristol, Bristol, UK
| | - Jules Brown
- Department of Anaesthesia and Intensive Care Medicine, North Bristol NHS Trust, Bristol, UK
| |
Collapse
|
13
|
Virchow JC, Li VW, Fonseca E, Salmen H, Martin A, Brady J, Jannowitz C, Schelfhout J. Chronic cough in Germany: results from a general-population survey. ERJ Open Res 2022; 8:00420-2021. [PMID: 35036416 PMCID: PMC8752938 DOI: 10.1183/23120541.00420-2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 09/22/2021] [Indexed: 11/05/2022] Open
Abstract
Background Chronic cough (CC) which is defined ≥8 weeks is a common condition in clinical practice. However, estimates of prevalence and associated comorbidities in German adults and key subgroups of age and gender are lacking. Methods Cross-sectional study based on a representative panel of 15 020 adult subjects of the general population who completed the German National Health and Wellness Survey, reporting CC and questions about comorbidities. Lifetime and 12-month prevalence are presented as unweighted estimates. Results The lifetime CC prevalence was 6.5% (range across age groups 5.1%-8.3%) and the 12-month prevalence was 4.9% (range 3.7-5.7%). The prevalence of diagnosed CC was 2.8% (range 0.9-4.1%) and the prevalence of persons currently on any prescription to treat CC was 0.6% (range 0.2-1.4%). Respondents who experienced CC were 52.0±17.0 years old, with a higher prevalence in those aged 50 years and older. Persons with CC had higher morbidity scores and were diagnosed with an increased number of comorbidities, most frequently diagnoses of the respiratory system (71.0%), followed by digestive tract disorders (34.0%) and sleep disorders (37.6%). Conclusions In a broadly representative sample of German adults, lifetime and 12-month prevalence of CC was greatest in current and former smokers and those older ≥50 years of age. Comorbidities are frequent and may complicate management of these patients.
Collapse
Affiliation(s)
- J Christian Virchow
- Depts of Pneumology and Intensive Care Medicine, University of Rostock Medical Clinic, Rostock, Germany
| | - Vicky W Li
- Kantar Health Co., Inc., New York, NY, USA
| | | | | | | | | | | | | |
Collapse
|
14
|
Mootassim‐Billah S, Van Nuffelen G, Schoentgen J, De Bodt M, Dragan T, Digonnet A, Roper N, Van Gestel D. Assessment of cough in head and neck cancer patients at risk for dysphagia-An overview. Cancer Rep (Hoboken) 2021; 4:e1395. [PMID: 33932152 PMCID: PMC8551981 DOI: 10.1002/cnr2.1395] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/22/2021] [Accepted: 03/26/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND This literature review explores the terminology, the neurophysiology, and the assessment of cough in general, in the framework of dysphagia and regarding head and neck cancer patients at risk for dysphagia. In the dysphagic population, cough is currently assessed perceptually during a clinical swallowing evaluation or aerodynamically. RECENT FINDINGS Recent findings have shown intra and inter-rater disagreements regarding perceptual scoring of cough. Also, aerodynamic measurements are impractical in a routine bedside assessment. Coughing, however, is considered to be a clinically relevant sign of aspiration and dysphagia in head and cancer patients treated with concurrent chemoradiotherapy. CONCLUSION This article surveys the literature regarding the established cough assessment and stresses the need to implement innovative methods for assessing cough in head and neck cancer patients treated with concurrent chemoradiotherapy at risk for dysphagia.
Collapse
Affiliation(s)
- Sofiana Mootassim‐Billah
- Department of Radiation Oncology, Speech Therapy, Institut Jules BordetUniversité Libre de BruxellesBrusselsBelgium
| | - Gwen Van Nuffelen
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication DisordersAntwerp University HospitalAntwerpBelgium
- Department of Translational Neurosciences, Faculty of Medicine and Health SciencesUniversity of AntwerpAntwerpBelgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health SciencesUniversity of GhentGhentBelgium
| | - Jean Schoentgen
- BEAMS (Bio‐, Electro‐ And Mechanical Systems)Université Libre de BruxellesBrusselsBelgium
| | - Marc De Bodt
- Department of Otolaryngology and Head and Neck Surgery, University Rehabilitation Center for Communication DisordersAntwerp University HospitalAntwerpBelgium
- Department of Translational Neurosciences, Faculty of Medicine and Health SciencesUniversity of AntwerpAntwerpBelgium
- Department of Logopaedics and Audiological Sciences, Faculty of Medicine and Health SciencesUniversity of GhentGhentBelgium
| | - Tatiana Dragan
- Department of Radiation Oncology, Head and Neck Unit, Institut Jules BordetUniversité Libre de BruxellesBrusselsBelgium
| | - Antoine Digonnet
- Department of Surgical Oncology, Head and Neck Surgery Unit, Institut Jules BordetUniversité Libre de BruxellesBrusselsBelgium
| | - Nicolas Roper
- Department of Oto‐Rhino‐Laryngology and Head & Neck Surgery, Erasme HospitalUniversité Libre de BruxellesBrusselsBelgium
| | - Dirk Van Gestel
- Department of Radiation Oncology, Head and Neck Unit, Institut Jules BordetUniversité Libre de BruxellesBrusselsBelgium
| |
Collapse
|
15
|
El-Hamamsy D, Watson A, Corden J, Smith ARB, Reid FM. An assessment of techniques and practices used to elevate intra-abdominal pressure when assessing pelvic floor dysfunction. Neurourol Urodyn 2021; 40:783-790. [PMID: 33527509 DOI: 10.1002/nau.24617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 11/25/2020] [Accepted: 01/11/2021] [Indexed: 11/07/2022]
Abstract
AIMS To determine terminology and methods for raising intra-abdominal pressure (IAP) currently used by clinicians to assess pelvic floor dysfunction (PFD) and to measure the effect of these maneuvers on IAP. METHODS Three-hundred questionnaires were distributed at two scientific meetings in the United Kingdom to determine methods clinicians used to raise IAP and their perceptions of these methods. Twenty healthy volunteers were also recruited to measure the effect of two methods of raising IAP: Valsalva maneuver (VM) and bear down maneuver (BDM). IAP pressure was measured with rectal catheters connected to pressure sensors. The IAP was measured during each maneuver in both standing and supine positions. RESULTS Maneuvers used in practice were cough (79%), BDM (60%), and VM (38%). 44% of clinicians felt patients found it difficult to raise their IAP. There was uncertainty among clinicians as to which method was the most effective in raising IAP and whether the different methods produced the same rise in IAP. On testing IAP in 20 healthy volunteers, median (interquartile range) IAP generated during BDM; 101 (59.1) cmH2 O was significantly higher than that generated during VM; 80.3 (43.6) cmH2 O (p < .0001). CONCLUSION Clinicians varied widely in the maneuvers they used to raise patients' IAP to test for PFD and there was uncertainty about the maneuvers' effect on IAP. In healthy volunteers, BDM produced significantly higher IAP than VM. We recommend standardization of terminology and techniques used to raise IAP when assessing PFD, to ensure consistency of diagnosis and assessment of treatment outcomes.
Collapse
Affiliation(s)
- Dina El-Hamamsy
- The Warrell Unit, Department of Urogynaecology, Manchester Academic Health Science Center, Saint Mary's Hospital., Manchester University NHS Foundation Trust, Manchester, UK
| | - Alison Watson
- The Warrell Unit, Department of Urogynaecology, Manchester Academic Health Science Center, Saint Mary's Hospital., Manchester University NHS Foundation Trust, Manchester, UK
| | - James Corden
- Research and Innovation Department, Manchester Academic Health Science Center, Manchester University NHS Foundation Trust, Manchester, UK
| | - Anthony R B Smith
- The Warrell Unit, Department of Urogynaecology, Manchester Academic Health Science Center, Saint Mary's Hospital., Manchester University NHS Foundation Trust, Manchester, UK.,Institute of Human Development, Faculty of Medical & Human Sciences, Manchester Academic Health Science Center, University of Manchester, Manchester, UK
| | - Fiona M Reid
- The Warrell Unit, Department of Urogynaecology, Manchester Academic Health Science Center, Saint Mary's Hospital., Manchester University NHS Foundation Trust, Manchester, UK.,Institute of Human Development, Faculty of Medical & Human Sciences, Manchester Academic Health Science Center, University of Manchester, Manchester, UK
| |
Collapse
|
16
|
Lee KK, Davenport PW, Smith JA, Irwin RS, McGarvey L, Mazzone SB, Birring SS. Global Physiology and Pathophysiology of Cough: Part 1: Cough Phenomenology - CHEST Guideline and Expert Panel Report. Chest 2021; 159:282-293. [PMID: 32888932 PMCID: PMC8640837 DOI: 10.1016/j.chest.2020.08.2086] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 12/12/2022] Open
Abstract
The purpose of this state-of-the-art review is to update the American College of Chest Physicians 2006 guideline on global physiology and pathophysiology of cough. A review of the literature was conducted using PubMed and MEDLINE databases from 1951 to 2019 and using prespecified search terms. We describe the basic phenomenology of cough patterns, behaviors, and morphological features. We update the understanding of mechanical and physiological characteristics of cough, adding a contemporary view of the types of cough and their associated behaviors and sensations. New information about acoustic characteristics is presented, and recent insights into cough triggers and the patient cough hypersensitivity phenotype are explored. Lastly, because the clinical assessment of patients largely focuses on the duration rather than morphological features of cough, we review the morphological features of cough that can be measured in the clinic. This is the first of a two-part update to the American College of Chest Physicians 2006 cough guideline; it provides a more global consideration of cough phenomenology, beyond simply the mechanical aspects of a cough. A greater understanding of the typical features of cough, and their variations, may allow a more informed interpretation of cough measurements and the clinical relevance for patients.
Collapse
Affiliation(s)
- Kai K Lee
- School of Immunology and Microbial Sciences, Faculty of Life Sciences and Medicine, King's College London, London, England
| | - Paul W Davenport
- Department of Physiological Sciences, University of Florida, Gainesville, FL
| | - Jaclyn A Smith
- Division of Infection, Immunity and Respiratory Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, England
| | - Richard S Irwin
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, UMass Memorial Medical Center, Worcester, MA
| | - Lorcan McGarvey
- Centre for Experimental Medicine, Department of Medicine, Queen's University Belfast, Belfast, Northern Ireland.
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, The University of Melbourne, Melbourne, VIC, Australia.
| | - Surinder S Birring
- Centre for Human and Applied Physiological Sciences, Faculty of Life Sciences and Medicine, King's College London, London, England
| |
Collapse
|
17
|
Valentin S, Chenuel B, Demoulin-Alexikova S, Demoulin B, Gérard D, Foucaud L, Poussel M. Desensitization of the Cough Reflex Induced by Corticosteroids in Ovalbumin-Sensitized Rabbits During Artificial Limb Exercise. Front Physiol 2020; 11:466. [PMID: 32528305 PMCID: PMC7247830 DOI: 10.3389/fphys.2020.00466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 04/16/2020] [Indexed: 11/13/2022] Open
Abstract
Introduction Cough is a major symptom frequently experienced during exercise, mainly in asthmatic patients. Inhaled glucocorticoids represent the keystone treatment in the management of asthma, but little is known about interactions between cough and exercise, especially in controlled patients. During exercise, cough reflex (CR) appears downregulated in healthy animal models whereas a lack of desensitization of CR has been shown in ovalbumin-sensitized animal models, mimicking asthmatic disease. Aims and Objectives The goal of our study was to clarify the potential modulation of the CR induced by inhaled corticosteroids (CS) in ovalbumin (OVA) sensitized rabbits during artificial limb exercise. Materials and Methods Seventeen OVA sensitized rabbits were studied. Among them, 9 were treated with CS delivered intravenously (OVA-Corticoids). The ventilatory response to direct tracheal stimulation, performed at rest and during exercise, was determined to assess the incidence and the sensitivity of the CR. Broncho-alveolar lavage (BAL) and cell counts were performed to determine the level of airway inflammation. Exercise was mimicked by electrically induced hindlimb muscular contractions (EMC). Results Compared to rest values, EMC increased minute ventilation by 28% without any decrease in respiratory resistance (Rsr). Among 322 tracheal stimulations, 172 (53%) were performed at rest and 150 (47%) during exercise. The sensitivity of CR decreased during artificial limb exercise compared to baseline in OVA-Corticoids rabbits (p = 0.0313) while it remained unchanged in OVA rabbits (p = NS). Conclusion Corticosteroids appear to restore the desensitization of the CR in OVA sensitized rabbits during artificial limb exercise, suggesting the potential role of airway inflammation in the pathophysiology of cough during exercise in asthmatics.
Collapse
Affiliation(s)
- Simon Valentin
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France.,Department of Pneumology, CHRU Nancy, Nancy, France
| | - Bruno Chenuel
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France.,Pulmonary Function Testing and Exercise Physiology, CHRU Nancy, Nancy, France
| | - Silvia Demoulin-Alexikova
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France
| | - Bruno Demoulin
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France
| | | | - Laurent Foucaud
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France
| | - Mathias Poussel
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory Regulations and Motor Control, Université de Lorraine, Nancy, France.,Pulmonary Function Testing and Exercise Physiology, CHRU Nancy, Nancy, France
| |
Collapse
|
18
|
Spinou A. A Review on Cough Augmentation Techniques: Assisted Inspiration, Assisted Expiration and Their Combination. Physiol Res 2020; 69:S93-S103. [DOI: 10.33549/physiolres.934407] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cough is an important mechanism of airway clearance. In patients who present weak and ineffective cough, augmentation techniques aim to assist or simulate the maneuver. These techniques target different phases of the cough cycle, mainly the inspiratory and expiratory phases, through assisted inspiration, assisted expiration and their combination. They include the manual hyperinflation, ventilator hyperinflation, glossopharyngeal breathing, manually assisted cough and mechanical insufflator-exsufflator, each applied individually or in different combinations. The aim of this review is to investigate the effectiveness and safety of cough augmentation techniques. Findings support that all commonly used techniques can theoretically improve airway clearance, as they generate higher cough peak flows compared to unassisted cough. Still, the studies assessing cough augmentation present considerable limitations and the direct comparison of different techniques is challenging. Current evidence indicate that cough peak flow shows higher increase with the combination of assisted inspiration and expiration, and improvement is greater in patients with lower unassisted values. Associated adverse events are infrequent.
Collapse
Affiliation(s)
- A. Spinou
- Population Health Sciences, Faculty of Life Sciences and Medicine, King’s College London, United Kingdom.
| |
Collapse
|
19
|
Addington WR, Stephens RE, Miller SP. Involuntary cough is superior to voluntary cough for identifying stress urinary incontinence. Cent European J Urol 2020; 72:378-383. [PMID: 32015907 PMCID: PMC6979552 DOI: 10.5173/ceju.2019.1986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/18/2019] [Accepted: 10/29/2019] [Indexed: 11/22/2022] Open
Abstract
Introduction Voluntary cough (VC) and the laryngeal expiration reflex (LER) provoke stress urinary incontinence (SUI). The aim of this article is to analyze the effectiveness of these stimuli on the timing of urinary leaks. Material and methods Urodynamic testing using pressure catheters was performed on 123 subjects with history of SUI. The LER was triggered using the induced reflex cough test (iRCT). Each subject was tested with VC and LER and leaked with one or both stimuli. The occurrence and timing of leaks were recorded. Results The peak and average intra-abdominal pressures were 16-19% greater for LER compared to VC. Of the 123 subjects, LER caused leak in 118 (96%), VC in 71 (58%) and both in 66 (54%). For LER compared to VC, leak was more likely to occur during or immediately after the first expiratory effort. The electromyogram for VC and LER were similar. Conclusions The iRCT reliably initiated the LER and triggered SUI more effectively than VC. During VC, the smooth muscle of the internal urethral sphincter (IUS) starts to contract during inspiration, and constriction of the IUS continues into the expiratory phase; this increased urethral tonicity would lessen the likelihood of SUI. We refer to this as the inspiration closure reflex (ICR). With LER the inspiration would not take place, and the first expiratory effort would be against a non-constricted IUS, making leak more likely. Our findings disprove the pressure transmission theory. The internal and external urethral sphincters may both increase urethral closure pressure and resistance.
Collapse
Affiliation(s)
| | - Robert E Stephens
- Department of Anatomy, Kansas City University of Medicine and Biosciences, Kansas City, MO, USA
| | | |
Collapse
|
20
|
Irons JY, Petocz P, Kenny DT, Chang AB. Singing as an adjunct therapy for children and adults with cystic fibrosis. Cochrane Database Syst Rev 2019; 7:CD008036. [PMID: 31425607 PMCID: PMC6699649 DOI: 10.1002/14651858.cd008036.pub5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Cystic fibrosis is a genetically inherited, life-threatening condition that affects major organs. The management of cystic fibrosis involves a multi-faceted daily treatment regimen that includes airway clearance techniques, pancreatic enzymes and other medications. Previous studies have found that compliance with this intensive treatment is poor, especially among adolescents. Because of both the nature and consequences of the illness and the relentless demands of the treatment, many individuals with cystic fibrosis have a poor quality of life. Anecdotal reports suggest that singing may provide both appropriate exercise for the whole respiratory system and a means of emotional expression which may enhance quality of life. This is an update of a previously published review. OBJECTIVES To evaluate the effects of singing as an adjunct therapy to standard treatment on the quality of life, morbidity, respiratory muscle strength and pulmonary function of children and adults with cystic fibrosis. SEARCH METHODS We searched the Group's Cystic Fibrosis Trials Register and the Cochrane Central Register of Controlled Trials. Date of latest search: 07 January 2019.We also searched major allied complementary data bases, and clinical trial registers. Additionally, we handsearched relevant conference proceedings and journals. Date of latest search: 28 March 2019. SELECTION CRITERIA Randomised controlled trials in which singing (as an adjunct intervention) is compared with either a control intervention (for example, playing computer games or doing craft activities) or no singing in people with cystic fibrosis. DATA COLLECTION AND ANALYSIS Results of searches were reviewed against pre-determined criteria for inclusion. Only one eligible trial was available for analysis. MAIN RESULTS Since only one small study (n = 40) was included, no meta-analysis could be performed. The included randomised controlled study was of parallel design and undertaken at two paediatric hospitals in Australia. The study evaluated the effects of a singing program on the quality of life and respiratory muscle strength of hospitalised children with cystic fibrosis (mean age 11.6 years, 35% male). While the singing group received eight individual singing sessions, the control group participated in preferred recreational activities, such as playing computer games or watching movies. This study was limited by a small sample size (51 participants) and a high drop-out rate (21%). There were no differences between the groups at either post-intervention or follow-up; although by the end of treatment there were some improvements in some of the domains of the quality of life questionnaire Cystic Fibrosis Questionnaire-Revised (e.g. emotional, social and vitality domains) for both singing and control groups. For the respiratory muscle strength indices, maximal expiratory pressure at follow-up (six to eight weeks post-intervention) was higher in the singing group, mean difference 25.80 (95% confidence interval 5.94 to 45.66). There was no difference between groups for any of the other respiratory function parameters (maximal inspiratory pressure, spirometry) at either post-intervention or follow-up. No adverse effects were observed in the singing group; adverse events for the control group were not reported in the paper. AUTHORS' CONCLUSIONS There is insufficient evidence to determine the effects of singing on quality of life or on the respiratory parameters in people with cystic fibrosis. However, there is growing interest in non-medical treatments for cystic fibrosis and researchers may wish to investigate the impact of this inexpensive therapy on respiratory function and psychosocial well-being further in the future.
Collapse
Affiliation(s)
- J. Yoon Irons
- University of DerbyHealth and Social Care Research CentreDerbyUK
| | - Peter Petocz
- Macquarie UniversityDepartment of StatisticsEastern RoadSydneyNSWAustralia2109
| | - Dianna Theadora Kenny
- University of SydneyBehavioural and Social Sciences in Health, Faculty of Health SciencesEast StLidcombeNSWAustralia1825
| | - Anne B Chang
- Menzies School of Health Research, Charles Darwin UniversityChild Health DivisionPO Box 41096DarwinNorthern TerritoriesAustralia0811
| | | |
Collapse
|
21
|
McGarvey L, Gibson PG. What Is Chronic Cough? Terminology. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY-IN PRACTICE 2019; 7:1711-1714. [DOI: 10.1016/j.jaip.2019.04.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/01/2019] [Accepted: 04/05/2019] [Indexed: 11/29/2022]
|
22
|
Ferasin L, Linney C. Coughing in dogs: what is the evidence for and against a cardiac cough? J Small Anim Pract 2019; 60:139-145. [PMID: 30652329 DOI: 10.1111/jsap.12976] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 10/16/2018] [Accepted: 12/05/2018] [Indexed: 01/06/2023]
Abstract
Cough has been historically reported as a major clinical sign of cardiogenic pulmonary oedema in dogs. However, recent evidence appears to contradict the traditional dogmatic approach that linked cough to congestive heart failure in dogs. Here we use a question-based format to introduce and discuss the modern evidence regarding "cardiac cough" and the interpretation of this important but often misleading clinical sign.
Collapse
Affiliation(s)
- L Ferasin
- Lumbry Park Veterinary Specialists, Alton, Hampshire, GU34 3HL, UK
| | - C Linney
- Willows Veterinary Referral Service, Solihull, West Midlands B90 4NH, UK
| |
Collapse
|
23
|
Norisue Y, Kataoka J, Homma Y, Naito T, Tsukuda J, Okamoto K, Kawaguchi T, Ashworth L, Yumiko S, Hoshina Y, Hiraoka E, Fujitani S. Increase in intra-abdominal pressure during airway suctioning-induced cough after a successful spontaneous breathing trial is associated with extubation outcome. Ann Intensive Care 2018; 8:61. [PMID: 29740716 PMCID: PMC5940967 DOI: 10.1186/s13613-018-0410-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 05/03/2018] [Indexed: 12/20/2022] Open
Abstract
Background A patient’s ability to clear secretions and protect the airway with an effective cough is an important part of the pre-extubation evaluation. An increase in intra-abdominal pressure (IAP) is important in generating the flow rate necessary for a cough. This study investigated whether an increase from baseline in IAP during a coughing episode induced by routine pre-extubation airway suctioning is associated with extubation outcome after a successful spontaneous breathing trial (SBT). Methods Three hundred thirty-five (335) mechanically ventilated patients who passed an SBT were enrolled. Baseline IAP and peak IAP during successive suctioning-induced coughs were measured with a fluid column connected to a Foley catheter. Results Extubation was unsuccessful in 24 patients (7.2%). Unsuccessful extubation was 3.40 times as likely for patients with a delta IAP (ΔIAP) of ≤ 30 cm H2O than for those with a ΔIAP > 30 cm H2O, after adjusting for APACHE II score (95% CI, 1.39–8.26; p = .007). Conclusion ΔIAP during a coughing episode induced by routine pre-extubation airway suctioning is significantly associated with extubation outcome in patients with a successful SBT. Trial registration UMIN-CTR Clinical Trial, UMIN000017762. Registered 1 June 2015.
Collapse
Affiliation(s)
- Yasuhiro Norisue
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan. .,Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan. .,Department of Pulmonary and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan.
| | - Jun Kataoka
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan
| | - Yosuke Homma
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan
| | - Takaki Naito
- Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan
| | - Junpei Tsukuda
- Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan
| | - Kentaro Okamoto
- Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan
| | - Takeshi Kawaguchi
- Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan
| | - Lonny Ashworth
- Department of Respiratory Care, Boise State University, 1910 W University Drive, Boise, ID, 83725, USA
| | - Shimada Yumiko
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan
| | - Yuiko Hoshina
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan
| | - Eiji Hiraoka
- Department of Emergency and Critical Care Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, 3-4-32 Todaijima, Urayasu, Chiba, 2790001, Japan
| | - Shigeki Fujitani
- Department of Emergency and Critical Care Medicine, St. Marianna University Hospital, 2-16-1 Sugao, Kawasaki, Kanagawa, 2168511, Japan
| |
Collapse
|
24
|
Fischer P, Gross V, Kroenig J, Weissflog A, Hildebrandt O, Sohrabi K, Koehler U. Description of nighttime cough epochs in patients with stable COPD GOLD II-IV. Int J Chron Obstruct Pulmon Dis 2018; 13:1071-1078. [PMID: 29662309 PMCID: PMC5892620 DOI: 10.2147/copd.s154539] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Chronic cough is one of the main symptoms of COPD. Ambulatory objective monitoring provides novel insights into the determinants and characteristics of nighttime cough in COPD. Materials and methods Nighttime cough was monitored objectively by LEOSound lung sound monitor in patients with stable COPD II–IV. In 30 patients, with 10 patients in each stage group, nighttime cough was analyzed for epoch frequency, epoch severity (epoch length and coughs per epoch), and pattern (productive or nonproductive). Results Cough was found in all patients ranging from 1 to 294 events over the recording period. In 29 patients, cough epochs were monitored, ranging from 1 to 75 epochs. The highest amount of cough epochs was found in patients with COPD stage III. Active smokers had significantly more productive cough epochs (61%) than nonsmokers (24%). Conclusion We found a high rate of nighttime cough epochs in patients with COPD, especially in those in stage III. Productive cough was predominantly found in patients with persistent smoking. LEOSound lung sound monitor offers a practical and valuable opportunity to evaluate cough objectively.
Collapse
Affiliation(s)
- Patrick Fischer
- Faculty of Health Sciences, University of Applied Sciences, Giessen, Germany
| | - Volker Gross
- Faculty of Health Sciences, University of Applied Sciences, Giessen, Germany
| | - Johannes Kroenig
- Department of Pneumology, Intensive Care and Sleep Medicine, University Hospital of Marburg and Giessen, Marburg, Germany
| | | | - Olaf Hildebrandt
- Department of Pneumology, Intensive Care and Sleep Medicine, University Hospital of Marburg and Giessen, Marburg, Germany
| | - Keywan Sohrabi
- Faculty of Health Sciences, University of Applied Sciences, Giessen, Germany.,Institute for Medical Informatics, Justus-Liebig-University Giessen, Giessen, Germany
| | - Ulrich Koehler
- Department of Pneumology, Intensive Care and Sleep Medicine, University Hospital of Marburg and Giessen, Marburg, Germany
| |
Collapse
|
25
|
Inhibitory modulation of the cough reflex by acetylcholine in the caudal nucleus tractus solitarii of the rabbit. Respir Physiol Neurobiol 2018; 257:93-99. [PMID: 29369803 DOI: 10.1016/j.resp.2018.01.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 01/08/2018] [Accepted: 01/15/2018] [Indexed: 12/16/2022]
Abstract
A cholinergic system has been described in the nucleus tractus solitarii (NTS). However, no information is available on the role played by acetylcholine (ACh) in the modulation of the cough reflex within the caudal NTS that has an important function in cough regulation. We addressed this issue making use of bilateral microinjections (30-50 nl) of 10 mM ACh combined with 5 mM physostigmine as well as of 10 mM mecamylamine or 10 mM scopolamine into the caudal NTS of pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Microinjections of ACh/physostigmine caused depressant effects on the cough reflex induced by mechanical and chemical stimulation of the tracheobronchial tree. They also elicited transient increases in respiratory frequency and decreases in abdominal activity. These effects were prevented by scopolamine, but not by mecamylamine. The results show for the first time that ACh exerts an inhibitory modulation of the cough reflex through muscarinic receptors within the caudal NTS. They also may provide hints for novel antitussive approaches.
Collapse
|
26
|
Mills C, Jones R, Huckabee ML. Measuring voluntary and reflexive cough strength in healthy individuals. Respir Med 2017; 132:95-101. [DOI: 10.1016/j.rmed.2017.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 09/04/2017] [Accepted: 09/25/2017] [Indexed: 01/03/2023]
|
27
|
Singing as an adjunct therapy for children and adults with cystic fibrosis: A Cochrane review summary. Int J Nurs Stud 2017; 82:163-164. [PMID: 29055499 DOI: 10.1016/j.ijnurstu.2017.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
28
|
Lin RL, Gu Q, Khosravi M, Lee LY. Sustained sensitizing effects of tumor necrosis factor alpha on sensory nerves in lung and airways. Pulm Pharmacol Ther 2017; 47:29-37. [PMID: 28587842 DOI: 10.1016/j.pupt.2017.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 05/30/2017] [Accepted: 06/03/2017] [Indexed: 01/07/2023]
Abstract
Tumor necrosis factor alpha (TNFα) plays a significant role in the pathogenesis of airway inflammatory diseases. Inhalation of aerosolized TNFα induced airway hyperresponsiveness accompanied by airway inflammation in healthy human subjects, but the underlying mechanism is not fully understood. We recently reported a series of studies aimed to investigate if TNFα elevates the sensitivity of vagal bronchopulmonary sensory nerves in a mouse model; these studies are summarized in this mini-review. Our results showed that intratracheal instillation of TNFα induced pronounced airway inflammation 24 h later, as illustrated by infiltration of eosinophils and neutrophils and the release of inflammatory mediators and cytokines in the lung and airways. Accompanying these inflammatory reactions, the sensitivity of vagal pulmonary C-fibers and silent rapidly adapting receptors to capsaicin, a selective agonist of transient receptor potential vanilloid type 1 receptor, was markedly elevated after the TNFα treatment. A distinct increase in the sensitivity to capsaicin induced by TNFα was also observed in isolated pulmonary sensory neurons, suggesting that the sensitizing effect is mediated primarily through a direct action of TNFα on these neurons. Furthermore, the same TNFα treatment also induced a lingering (>7days) cough hyperresponsiveness to inhalation challenge of NH3 in awake mice. Both the airway inflammation and the sensitizing effect on pulmonary sensory neurons caused by the TNFα treatment were abolished in the TNF-receptor double homozygous mutant mice, indicating the involvement of TNF-receptor activation. These findings suggest that the TNFα-induced hypersensitivity of vagal bronchopulmonary afferents may be responsible for, at least in part, the airway hyperresponsiveness caused by inhaled TNFα in healthy individuals.
Collapse
Affiliation(s)
- Ruei-Lung Lin
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Qihai Gu
- Department of Biomedical Sciences, Mercer University, Macon, GA, USA
| | - Mehdi Khosravi
- Department of Medicine, University of Kentucky, Lexington, KY, USA
| | - Lu-Yuan Lee
- Department of Physiology, University of Kentucky, Lexington, KY, USA.
| |
Collapse
|
29
|
Zhang C, Lin RL, Hong J, Khosravi M, Lee LY. Cough and expiration reflexes elicited by inhaled irritant gases are intensified in ovalbumin-sensitized mice. Am J Physiol Regul Integr Comp Physiol 2017; 312:R718-R726. [PMID: 28228416 DOI: 10.1152/ajpregu.00444.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 02/16/2017] [Accepted: 02/16/2017] [Indexed: 01/09/2023]
Abstract
This study was designed to determine the effect of active sensitization with ovalbumin (Ova) on cough responses to inhaled irritant gases in mice. Conscious mice moved freely in a recording chamber, while the pressure change in the chamber and audio and video signals of the mouse movements were recorded simultaneously to measure the frequencies of cough reflex (CR) and expiration reflex (ER). To further verify the accuracy of cough analysis, the intrapleural pressure was also recorded by a telemetry sensor surgically implanted in the intrapleural space in a subgroup of mice. During the irritant gas inhalation challenge, sulfur dioxide (SO2; 200 and 400 ppm) or ammonia (NH3; 0.1% and 0.2%) was drawn into the chamber at a constant flow rate for 8 min. Ova sensitization and sham sensitization with vehicle (Veh) were performed over a 25-day period in separate groups of mice. Our results showed that 1) both SO2 and NH3 inhalation challenges increased CR and ER frequencies in a concentration-dependent manner before Ova sensitization; 2) the baseline CR frequency was significantly elevated after Ova sensitization, accompanied by pronounced airway inflammation; and 3) Ova sensitization also markedly augmented the responses of CR and ER to both SO2 and NH3 inhalation challenges; in sharp contrast, the cough responses did not change after sham sensitization in the Veh group. In conclusion, Ova sensitization caused distinct and lingering increases in baseline cough frequency, and also intensified both CR and ER responses to inhaled irritant gases, which probably resulted from an allergic inflammation-induced hypersensitivity of airway sensory nerves.
Collapse
Affiliation(s)
- Cheng Zhang
- Department of Physiology, University of Kentucky, Lexington, Kentucky.,Department of Respiratory Medicine, Guizhou Provincial People's Hospital, Guiyang, Guizhou, China
| | - Ruei-Lung Lin
- Department of Physiology, University of Kentucky, Lexington, Kentucky
| | - Jeff Hong
- Department of Physiology, University of Kentucky, Lexington, Kentucky
| | - Mehdi Khosravi
- Department of Medicine, University of Kentucky, Lexington, Kentucky; and
| | - Lu-Yuan Lee
- Department of Physiology, University of Kentucky, Lexington, Kentucky;
| |
Collapse
|
30
|
Coutier-Marie L, Ioan I, Bonabel C, Demoulin B, Leblanc AL, Debitu L, Schweitzer C, Marchal F, Demoulin-Alexikova S. Maturation of Airway Defensive Reflexes Is Related to Development of Feeding Behavior during Growth in Rabbits. Front Physiol 2017; 8:64. [PMID: 28228733 PMCID: PMC5296324 DOI: 10.3389/fphys.2017.00064] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 01/24/2017] [Indexed: 01/01/2023] Open
Abstract
Introduction: Cough and expiration reflex are major lower airway defense mechanisms that have not been studied throughout development in relation with the feeding behavior. Aim: To describe airway defense reflexes evoked by mechanical stimulation of the trachea in developing rabbit pups. Material and Methods: Sixty one pups were allocated to 3 groups according to their feeding behavior: suckling (n = 22), weanling (n = 21) and weaning (n = 18) group. The incidence and sensitivity of defense reflexes triggered by mechanical tracheal stimulation were studied in anesthetized and tracheotomized animals. Data are expressed as median (25th to 75th percentile). Results: The overall incidence of defensive responses (cough and/or expiration reflex) was found to be significantly higher in suckling [100% (50–100%); p = 0.01] and weanling [75% (40–100%); p = 0.05] animals when compared to weaning ones [37.5% (0–75%)]. However, cough motor pattern accounted for only 29% (0–62%) of all defensive responses in suckling rabbits and its frequency was significantly lower in this group when compared with weanling [100%(50–100%); p = 0.006] or weaning group [62%(50–100%), p = 0.05]. In other word the expiration reflex was the dominant response in suckling animals. Conclusion: Incidence and motor pattern of defensive responses were found to be linked to the pup feeding behavior and the expiration reflex was the major response triggered in suckling pups. The results suggest that this reflex is especially fitted to occur during the coordinated swallowing - breathing fast activities of sucking.
Collapse
Affiliation(s)
- Laurianne Coutier-Marie
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de LorraineVandœuvre-lès-Nancy, France; Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'EnfantsVandœuvre-lès-Nancy, France; Service de Pneumologie, Hôpital Femme-Mère-Enfant, Hospices Civils de LyonLyon, France
| | - Iulia Ioan
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de LorraineVandœuvre-lès-Nancy, France; Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'EnfantsVandœuvre-lès-Nancy, France
| | - Claude Bonabel
- Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'Enfants Vandœuvre-lès-Nancy, France
| | - Bruno Demoulin
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de Lorraine Vandœuvre-lès-Nancy, France
| | - Anne-Laure Leblanc
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de Lorraine Vandœuvre-lès-Nancy, France
| | - Ludivine Debitu
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de Lorraine Vandœuvre-lès-Nancy, France
| | - Cyril Schweitzer
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de LorraineVandœuvre-lès-Nancy, France; Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'EnfantsVandœuvre-lès-Nancy, France
| | - François Marchal
- Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'Enfants Vandœuvre-lès-Nancy, France
| | - Silvia Demoulin-Alexikova
- EA 3450DevAH - Laboratoire de Physiologie, Faculté de Médicine, Université de LorraineVandœuvre-lès-Nancy, France; Service d'Explorations Fonctionnelles Pédiatriques, Hôpital d'EnfantsVandœuvre-lès-Nancy, France
| |
Collapse
|
31
|
Irons JY, Petocz P, Kenny DT, Chang AB. Singing as an adjunct therapy for children and adults with cystic fibrosis. Cochrane Database Syst Rev 2016; 9:CD008036. [PMID: 27629557 PMCID: PMC6457756 DOI: 10.1002/14651858.cd008036.pub4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Cystic fibrosis is a genetically inherited, life-threatening condition that affects major organs. The management of cystic fibrosis involves a multi-faceted daily treatment regimen that includes airway clearance techniques, pancreatic enzymes and other medications. Previous studies have found that compliance with this intensive treatment is poor, especially among adolescents. Because of both the nature and consequences of the illness and the relentless demands of the treatment, many individuals with cystic fibrosis have a poor quality of life. Anecdotal reports suggest that singing may provide both appropriate exercise for the whole respiratory system and a means of emotional expression which may enhance quality of life. This is an update of a previously published review. OBJECTIVES To evaluate the effects of singing as an adjunct therapy to standard treatment on the quality of life, morbidity, respiratory muscle strength and pulmonary function of children and adults with cystic fibrosis. SEARCH METHODS We searched the Group's Cystic Fibrosis Trials Register and the Cochrane Central Register of Controlled Trials. Date of latest search: 18 February 2016.We also searched major allied complementary data bases, and clinical trial registers. Additionally, we handsearched relevant conference proceedings and journals. Date of latest search: 18 February 2016. SELECTION CRITERIA Randomised controlled trials in which singing (as an adjunct intervention) is compared with either a control intervention (for example, playing computer games or doing craft activities) or no singing in people with cystic fibrosis. DATA COLLECTION AND ANALYSIS Results of searches were reviewed against pre-determined criteria for inclusion. Only one eligible trial was available for analysis. MAIN RESULTS Since only one small study (n = 40) was included, no meta-analysis could be performed. The included randomised controlled study was of parallel design and undertaken at two paediatric hospitals in Australia. The study evaluated the effects of a singing program on the quality of life and respiratory muscle strength of hospitalised children with cystic fibrosis (mean age 11.6 years, 35% male). While the singing group received eight individual singing sessions, the control group participated in preferred recreational activities, such as playing computer games or watching movies. This study was limited by a small sample size (51 participants) and a high drop-out rate (21%). There were no significant differences between the groups at either post-intervention or follow up; although by the end of treatment there were some within-group statistically significant increases for both singing and control groups in some of the domains of the quality of life questionnaire Cystic Fibrosis Questionnaire-Revised (e.g. emotional, social and vitality domains). For the respiratory muscle strength indices, maximal expiratory pressure at follow up (six to eight weeks post-intervention) was higher in the singing group, mean difference 25.80 (95% confidence interval 5.94 to 45.66). There was no significant difference between groups for any of the other respiratory function parameters (maximal inspiratory pressure, spirometry) at either post-intervention or follow up. AUTHORS' CONCLUSIONS There is insufficient evidence to determine the effects of singing on quality of life or on the respiratory parameters in people with cystic fibrosis. However, there is growing interest in non-medical treatments for cystic fibrosis and researchers may wish to investigate the impact of this inexpensive therapy on respiratory function and psychosocial well-being further in the future.
Collapse
Affiliation(s)
- J. Yoon Irons
- South Bank Campus, Griffith UniversityQueensland Conservatorium Research Centre140 Grey StreetBrisbaneAustraliaQLD 4101
| | - Peter Petocz
- Macquarie UniversityDepartment of StatisticsEastern RoadSydneyAustralia2109
| | - Dianna Theadora Kenny
- University of SydneyBehavioural and Social Sciences in Health, Faculty of Health SciencesEast StLidcombeAustralia1825
| | - Anne B Chang
- Menzies School of Health Research, Charles Darwin UniversityChild Health DivisionPO Box 41096DarwinAustralia0811
| |
Collapse
|
32
|
Antitussive effect of carcainium chloride in patients with chronic cough and idiopathic interstitial pneumonias: A pilot study. Pulm Pharmacol Ther 2016; 40:91-4. [PMID: 27538683 DOI: 10.1016/j.pupt.2016.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/27/2016] [Accepted: 08/02/2016] [Indexed: 11/21/2022]
Abstract
BACKGROUND Cough is a common presenting symptom in patients with idiopathic interstitial pneumonia (IIP); it is often disabling, and lacks effective treatment. Studies in animals suggest that carcainium chloride, a quaternary derivative of the local anesthetic lidocaine, is able to inhibit experimentally induced cough by a mechanism of action distinct from that of lidocaine. OBJECTIVE To determine the effectiveness of aerosolised carcainium chloride (VRP700) in controlling cough in patients with IIP. METHODS Eight female patients (mean age 71 years) with IIP were investigated in a double blind, randomised, placebo controlled crossover, adaptive contingency study design (EudraCT Number 2010-021350-19). The study consisted of a screening visit to assess the eligibility of patients, and two separated (48-72 h) study days. On the two study days, patients were randomised to receive either nebulized VRP700 (1.0 mg/kg) on the first study visit followed by nebulised placebo (sodium chloride 0.9%) on the second visit, or placebo on the first visit followed by VRP700 on the second visit. The primary endpoint was cough frequency over a 4-h assessment period; secondary endpoints were subjective cough-related level of discomfort as assessed by a visual analogue scale (VAS) and the subjective response to treatment as assessed by a quality of life question. Safety (ECG, spirometry, urine and blood tests) and adverse events occurring during the trial were also investigated. RESULTS In all patients both VRP700 and placebo decreased cough frequency; however, mean decreases in cough frequency after treatment with VRP700 were significantly (P < 0.001) higher than with placebo. Similarly, mean reductions in VAS score were significantly (P < 0.001) higher after treatment with VRP 700 compared with placebo. All but one patient indicated that they felt better after receiving VRP700. No adverse events were reported during the study, nor were any changes in ECG variables, spirometry, urine and blood tests noted. CONCLUSION The results of this exploratory study indicate that nebulised VRP700 improved cough and quality of life in hospitalised IIP patients with no significant side effects. A larger trial is warranted to assess these promising results.
Collapse
|
33
|
Cinelli E, Iovino L, Bongianni F, Pantaleo T, Mutolo D. GABAA- and glycine-mediated inhibitory modulation of the cough reflex in the caudal nucleus tractus solitarii of the rabbit. Am J Physiol Lung Cell Mol Physiol 2016; 311:L570-80. [PMID: 27402692 DOI: 10.1152/ajplung.00205.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 07/05/2016] [Indexed: 01/05/2023] Open
Abstract
Cough-related sensory inputs from rapidly adapting receptors (RARs) and C fibers are processed by second-order neurons mainly located in the caudal nucleus tractus solitarii (NTS). Both GABAA and glycine receptors have been proven to be involved in the inhibitory control of second-order cells receiving RAR projections. We investigated the role of these receptors within the caudal NTS in the modulation of the cough reflex induced by either mechanical or chemical stimulation of the tracheobronchial tree in pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Bilateral microinjections (30-50 nl) of the receptor antagonists bicuculline and strychnine as well as of the receptor agonists muscimol and glycine were performed. Bicuculline (0.1 mM) and strychnine (1 mM) caused decreases in peak abdominal activity and marked increases in respiratory frequency due to decreases in both inspiratory time (Ti) and expiratory time (Te), without concomitant changes in arterial blood pressure. Noticeably, these microinjections induced potentiation of the cough reflex consisting of increases in the cough number associated with decreases either in cough-related Ti after bicuculline or in both cough-related Ti and Te after strychnine. The effects caused by muscimol (0.1 mM) and glycine (10 mM) were in the opposite direction to those produced by the corresponding antagonists. The results show that both GABAA and glycine receptors within the caudal NTS mediate a potent inhibitory modulation of the pattern of breathing and cough reflex responses. They strongly suggest that disinhibition is one important mechanism underlying cough regulation and possibly provide new hints for novel effective antitussive strategies.
Collapse
Affiliation(s)
- Elenia Cinelli
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Florence, Italy
| | - Ludovica Iovino
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Florence, Italy
| | - Fulvia Bongianni
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Florence, Italy
| | - Tito Pantaleo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Florence, Italy
| | - Donatella Mutolo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Florence, Italy
| |
Collapse
|
34
|
Mutolo D, Cinelli E, Iovino L, Pantaleo T, Bongianni F. Downregulation of the cough reflex by aclidinium and tiotropium in awake and anesthetized rabbits. Pulm Pharmacol Ther 2016; 38:1-9. [DOI: 10.1016/j.pupt.2016.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/08/2016] [Accepted: 04/10/2016] [Indexed: 01/23/2023]
|
35
|
Lee KK, Ward K, Rafferty GF, Moxham J, Birring SS. The Intensity of Voluntary, Induced, and Spontaneous Cough. Chest 2016; 148:1259-1267. [PMID: 26134718 DOI: 10.1378/chest.15-0138] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The intensity of cough is an important determinant of cough severity. Few studies have quantified cough intensity in patients with chronic cough with objective measures. We investigated the intensity of voluntary, induced, and spontaneous cough in patients with chronic cough and healthy control subjects. METHODS Patients with chronic cough and control subjects underwent physiologic assessment of the intensity of maximum voluntary, capsaicin-induced, and spontaneous cough. Assessments included measurement of gastric pressure (Pga) and esophageal pressure (Pes) during cough, peak cough flow (PCF), expiratory muscle strength (twitch gastric pressure [TwPga]), and cough compression phase duration (CPD). Subjective perception of cough intensity was assessed using a visual analog scale (VAS). RESULTS Pes, Pga, and PCF during maximum voluntary cough were significantly greater in patients with chronic cough compared with control subjects (P = .003-.042). There was no difference in TwPga between patients and control subjects. CPD was increased in female patients compared with control subjects (mean ± SD, 0.50 ± 0.22 s vs 0.28 ± 0.17 s; P = .007). Mean ± SD Pes during spontaneous cough was comparable to induced cough (128 ± 28 cm H2O vs 122 ± 37 cm H2O, P = .686) but less than maximum voluntary cough (170 ± 46 cm H2O, P = .020). Median within-subject correlation coefficients between cough intensity VAS and Pes, Pga, and PCF were r = 0.82 to 0.86. CONCLUSIONS Maximum voluntary cough intensity was increased in patients with chronic cough compared with control subjects. There was no significant difference in expiratory muscle contractility. Further studies should evaluate the compressive phase of cough in more detail. Physiologic measures of cough intensity correlated strongly with subjective perception of intensity in patients with chronic cough and may be relevant objective outcome measures for clinical studies.
Collapse
Affiliation(s)
- Kai K Lee
- Division of Asthma, Allergy and Lung Biology, King's College London, King's Health Partners, London, England
| | - Katie Ward
- Division of Asthma, Allergy and Lung Biology, King's College London, King's Health Partners, London, England
| | - Gerrard F Rafferty
- Division of Asthma, Allergy and Lung Biology, King's College London, King's Health Partners, London, England
| | - John Moxham
- Division of Asthma, Allergy and Lung Biology, King's College London, King's Health Partners, London, England
| | - Surinder S Birring
- Division of Asthma, Allergy and Lung Biology, King's College London, King's Health Partners, London, England.
| |
Collapse
|
36
|
Choi SH, Song DJ, Yum HY, Park YM, Rha YH. Chronic cough in children. ALLERGY ASTHMA & RESPIRATORY DISEASE 2016. [DOI: 10.4168/aard.2016.4.4.235] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Sun Hee Choi
- Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, Korea
| | - Dae Jin Song
- Department of Pediatrics, Korea University College of Medicine, Seoul, Korea
| | - Hye Yung Yum
- Atopy Asthma Center, Seoul Medical Center, Seoul, Korea
| | - Yong Mean Park
- Department of Pediatrics, Konkuk University School of Medicine, Seoul, Korea
| | - Yeong Ho Rha
- Department of Pediatrics, Kyung Hee University School of Medicine, Seoul, Korea
| |
Collapse
|
37
|
Abstract
Cough affects all individuals at different times, and its economic burden is substantial. Despite these widespread adverse effects, cough research relies on animal models, which hampers our understanding of the fundamental cause of cough. Postnasal drip is speculated to be one of the most frequent causes of chronic cough; however, this is a matter of debate. Here we show that mechanical stimuli by postnasal drip cause chronic cough. We distinguished human cough from sneezes and expiration reflexes by airflow patterns. Cough and sneeze exhibited one-peak and two-peak patterns, respectively, in expiratory airflow, which were also confirmed by animal models of cough and sneeze. Transgenic mice with ciliary dyskinesia coughed substantially and showed postnasal drip in the pharynx; furthermore, their cough was completely inhibited by nasal airway blockade of postnasal drip. We successfully reproduced cough observed in these mice by injecting artificial postnasal drip in wild-type mice. These results demonstrated that mechanical stimulation by postnasal drip evoked cough. The findings of our study can therefore be used to develop new antitussive drugs that prevent the root cause of cough.
Collapse
|
38
|
Cinelli E, Bongianni F, Pantaleo T, Mutolo D. The cough reflex is upregulated by lisinopril microinjected into the caudal nucleus tractus solitarii of the rabbit. Respir Physiol Neurobiol 2015; 219:9-17. [PMID: 26234277 DOI: 10.1016/j.resp.2015.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 07/27/2015] [Accepted: 07/27/2015] [Indexed: 11/16/2022]
Abstract
We have previously shown that cough potentiation induced by intravenous administration of the AT1 receptor antagonist losartan is lower than that induced by the ACE inhibitor lisinopril in anesthetized and awake rabbits. Since losartan and lisinopril cross the blood-brain barrier, their central action on the cough reflex can be hypothesized. Mechanical stimulation of the tracheobronchial tree and citric acid inhalation were used to induce cough reflex responses in pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Bilateral microinjections (30-50 nl) of losartan (5mM), lisinopril (1mM), bradykinin (0.05 mM), HOE-140 (0.2mM, a bradykinin B2 receptor antagonist) and CP-99,994 (1mM, an NK1 receptor antagonist) were performed into the caudal nucleus tractus solitarii, the predominant site of termination of cough-related afferents. Lisinopril, but not losartan increased the cough number. This effect was reverted by HOE-140 or CP-99,994. Cough potentiation was also induced by bradykinin. The results support for the first time a central protussive action of lisinopril mediated by an accumulation of bradykinin and substance P.
Collapse
Affiliation(s)
- Elenia Cinelli
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Viale G.B. Morgagni 63, 50134 Firenze, Italy
| | - Fulvia Bongianni
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Viale G.B. Morgagni 63, 50134 Firenze, Italy
| | - Tito Pantaleo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Viale G.B. Morgagni 63, 50134 Firenze, Italy
| | - Donatella Mutolo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Viale G.B. Morgagni 63, 50134 Firenze, Italy.
| |
Collapse
|
39
|
Mutolo D, Cinelli E, Bongianni F, Pantaleo T. Inhibitory control of the cough reflex by galanin receptors in the caudal nucleus tractus solitarii of the rabbit. Am J Physiol Regul Integr Comp Physiol 2014; 307:R1358-67. [DOI: 10.1152/ajpregu.00237.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The caudal nucleus tractus solitarii (NTS) is the main central station of cough-related afferents and a strategic site for the modulation of the cough reflex. The similarities between the characteristics of central processing of nociceptive and cough-related inputs led us to hypothesize that galanin, a neuropeptide implicated in the control of pain, could also be involved in the regulation of the cough reflex at the level of the NTS, where galanin receptors have been found. We investigated the effects of galanin and galnon, a nonpeptide agonist at galanin receptors, on cough responses to mechanical and chemical (citric acid) stimulation of the tracheobronchial tree. Drugs were microinjected (30–50 nl) into the caudal NTS of pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Galnon antitussive effects on cough responses to the mechanical stimulation of the airway mucosa via a custom-built device were also investigated. Bilateral microinjections of 1 mM galanin markedly decreased cough number, peak abdominal activity, and increased cough-related total cycle duration. Bilateral microinjections of 1 mM galnon induced mild depressant effects on cough, whereas bilateral microinjections of 10 mM galnon caused marked antitussive effects consistent with those produced by galanin. Galnon effects were confirmed by using the cough-inducing device. The results indicate that galanin receptors play a role in the inhibitory control of the cough reflex at the level of the caudal NTS and provide hints for the development of novel antitussive strategies.
Collapse
Affiliation(s)
- Donatella Mutolo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Firenze, Italy
| | - Elenia Cinelli
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Firenze, Italy
| | - Fulvia Bongianni
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Firenze, Italy
| | - Tito Pantaleo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze, Firenze, Italy
| |
Collapse
|
40
|
Turner RD, Bothamley GH. How to count coughs? Counting by ear, the effect of visual data and the evaluation of an automated cough monitor. Respir Med 2014; 108:1808-15. [DOI: 10.1016/j.rmed.2014.10.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 10/03/2014] [Accepted: 10/06/2014] [Indexed: 11/30/2022]
|
41
|
Lumb AB, Bradshaw K, Gamlin FMC, Heard J. The effect of coughing at extubation on oxygenation in the post-anaesthesia care unit. Anaesthesia 2014; 70:416-20. [DOI: 10.1111/anae.12924] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2014] [Indexed: 12/17/2022]
Affiliation(s)
- A. B. Lumb
- St James's University Hospital; Leeds UK
| | | | | | - J. Heard
- York Teaching Hospitals NHS Trust; York UK
| |
Collapse
|
42
|
Lee JY, Kim DK, Seo KM, Kang SH. Usefulness of the simplified cough test in evaluating cough reflex sensitivity as a screening test for silent aspiration. Ann Rehabil Med 2014; 38:476-84. [PMID: 25229026 PMCID: PMC4163587 DOI: 10.5535/arm.2014.38.4.476] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/23/2014] [Indexed: 01/24/2023] Open
Abstract
Objective To assess cough reflex sensitivity using the simplified cough test (SCT) and to evaluate the usefulness of SCT to screen for silent aspiration. Methods The healthy control group was divided into two subgroups: the young (n=29, 33.44±9.99 years) and the elderly (n=30, 63.66±4.37 years). The dysphagic elderly group (n=101, 72.95±9.19 years) consisted of patients with dysphagia, who suffered from a disease involving central nervous system (ischemic stroke 47, intracerebral hemorrhage 27, traumatic brain injury 11, encephalitis 5, hypoxic brain damage 3, and Parkinson disease 8). The SCT was performed using the mist of a 1% citric acid from a portable nebulizer. The time from the start of the inhalation to the first cough was measured as the cough latency. All the dysphagic patients underwent the videofluoroscopic swallowing study. Results The cough latency was more significantly prolonged in the healthy elderly group than in the healthy young group (p<0.001), and in the dysphagic elderly group than in the healthy elderly group (p<0.001). The sensitivity and specificity of SCT were 73.8% and 72.5% for detecting aspiration in the dysphagic patients, and 87.1% and 66.7% for detecting silent aspiration in the aspirated patients. Conclusion Cough latency measured with the SCT reflects the impairment of cough reflex in healthy elderly and dysphasic subjects. The results of this study show that the SCT test can be a valuable method of screening aspiration with or without cough in dysphasic patients.
Collapse
Affiliation(s)
- Ji Young Lee
- Department of Physical Medicine and Rehabilitation, Chung-Ang University College of Medicine, Seoul, Korea
| | - Don-Kyu Kim
- Department of Physical Medicine and Rehabilitation, Chung-Ang University College of Medicine, Seoul, Korea
| | - Kyung Mook Seo
- Department of Physical Medicine and Rehabilitation, Chung-Ang University College of Medicine, Seoul, Korea
| | - Si Hyun Kang
- Department of Physical Medicine and Rehabilitation, Chung-Ang University College of Medicine, Seoul, Korea
| |
Collapse
|
43
|
Ioan I, Poussel M, Coutier L, Plevkova J, Poliacek I, Bolser DC, Davenport PW, Derelle J, Hanacek J, Tatar M, Marchal F, Schweitzer C, Fontana G, Varechova S. What is chronic cough in children? Front Physiol 2014; 5:322. [PMID: 25221517 PMCID: PMC4148026 DOI: 10.3389/fphys.2014.00322] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 08/05/2014] [Indexed: 01/28/2023] Open
Abstract
The cough reflex is modulated throughout growth and development. Cough—but not expiration reflex—appears to be absent at birth, but increases with maturation. Thus, acute cough is the most frequent respiratory symptom during the first few years of life. Later on, the pubertal development seems to play a significant role in changing of the cough threshold during childhood and adolescence resulting in sex-related differences in cough reflex sensitivity in adulthood. Asthma is the major cause of chronic cough in children. Prolonged acute cough is usually related to the long-lasting effects of a previous viral airway infection or to the particular entity called protracted bacterial bronchitis. Cough pointers and type may orient toward specific etiologies, such as barking cough in croup or tracheomalacia, paroxystic whooping cough in Pertussis. Cough is productive in protracted bacterial bronchitis, sinusitis or bronchiectasis. Cough is usually associated with wheeze or dyspnea on exertion in asthma; however, it may be the sole symptom in cough variant asthma. Thus, pediatric cough has particularities differentiating it from adult cough, so the approach and management should be developmentally specific.
Collapse
Affiliation(s)
- Iulia Ioan
- Service D'explorations Fonctionnelles Pédiatriques, Hôpital D'enfants Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France
| | - Mathias Poussel
- Service Des Examens de la Fonction Respiratoire et de L'aptitude à L'exercice Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France ; EA 3450 DevAH - Laboratoire de Physiologie, Faculté de Médecine, Université Lorraine Vandoeuvre, France
| | - Laurianne Coutier
- EA 3450 DevAH - Laboratoire de Physiologie, Faculté de Médecine, Université Lorraine Vandoeuvre, France
| | - Jana Plevkova
- Department of Pathophysiology, Jessenius Faculty of Medicine, Comenius University Martin, Slovakia
| | - Ivan Poliacek
- Institute of Medical Biophysics, Jessenius Faculty of Medicine, Comenius University Martin, Slovakia
| | - Donald C Bolser
- Department of Physiological Sciences, University of Florida Gainesville, FL, USA
| | - Paul W Davenport
- Department of Physiological Sciences, University of Florida Gainesville, FL, USA
| | - Jocelyne Derelle
- Service de Médecine Infantile et de Génétique Clinique, Hôpital D'enfants Vandœuvre-lès-Nancy, France
| | - Jan Hanacek
- Department of Pathophysiology, Jessenius Faculty of Medicine, Comenius University Martin, Slovakia
| | - Milos Tatar
- Department of Pathophysiology, Jessenius Faculty of Medicine, Comenius University Martin, Slovakia
| | - François Marchal
- Service D'explorations Fonctionnelles Pédiatriques, Hôpital D'enfants Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France ; EA 3450 DevAH - Laboratoire de Physiologie, Faculté de Médecine, Université Lorraine Vandoeuvre, France
| | - Cyril Schweitzer
- Service D'explorations Fonctionnelles Pédiatriques, Hôpital D'enfants Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France ; EA 3450 DevAH - Laboratoire de Physiologie, Faculté de Médecine, Université Lorraine Vandoeuvre, France ; Service de Médecine Infantile et de Génétique Clinique, Hôpital D'enfants Vandœuvre-lès-Nancy, France
| | - Giovanni Fontana
- Department of Internal Medicine, University of Florence Florence, Italy
| | - Silvia Varechova
- Service D'explorations Fonctionnelles Pédiatriques, Hôpital D'enfants Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France ; EA 3450 DevAH - Laboratoire de Physiologie, Faculté de Médecine, Université Lorraine Vandoeuvre, France
| |
Collapse
|
44
|
Irons JY, Petocz P, Kenny DT, Chang AB. Singing as an adjunct therapy for children and adults with cystic fibrosis. Cochrane Database Syst Rev 2014:CD008036. [PMID: 24913722 DOI: 10.1002/14651858.cd008036.pub3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Cystic fibrosis is a genetically inherited, life-threatening condition that affects major organs. The management of cystic fibrosis involves a multi-faceted daily treatment regimen that includes airway clearance techniques, pancreatic enzymes and other medications. Previous studies have found that compliance with this intensive treatment is poor, especially among adolescents. Because of both the nature and consequences of the illness and the relentless demands of the treatment, many individuals with cystic fibrosis have a poor quality of life. Anecdotal reports suggest that singing may provide both appropriate exercise for the whole respiratory system and a means of emotional expression which may enhance quality of life. OBJECTIVES To evaluate the effects of singing as an adjunct therapy to standard treatment on the quality of life, morbidity, respiratory muscle strength and pulmonary function of children and adults with cystic fibrosis. SEARCH METHODS We searched the Group's Cystic Fibrosis Trials Register and the Cochrane Central Register of Controlled Trials. Date of latest search: 31 March 2014.We also searched major allied complementary data bases, and clinical trial registers. Additionally, we handsearched relevant conference proceedings and journals. Date of latest search: 24 May 2012. SELECTION CRITERIA Randomised controlled trials in which singing (as an adjunct intervention) is compared with either a control intervention (for example, playing computer games or doing craft activities) or no singing in people with cystic fibrosis. DATA COLLECTION AND ANALYSIS Results of searches were reviewed against pre-determined criteria for inclusion. Only one eligible trial was available for analysis. MAIN RESULTS Since only one small study was included, no meta-analysis could be performed. The included study was a parallel, randomised controlled trial undertaken at two paediatric hospitals in Australia. The study evaluated the effects of a singing program on the quality of life and respiratory muscle strength of hospitalised children with cystic fibrosis (mean age 11.6 years, 35% male). While the singing group received eight individual singing sessions, the control group participated in preferred recreational activities, such as playing computer games or watching movies. This study was limited by a small sample size (51 participants) and a high drop-out rate (21%). There were no significant differences between the groups at either post-intervention or follow up; although by the end of treatment there were some within-group statistically significant increases for both singing and control groups in some of the domains of the quality of life questionnaire Cystic Fibrosis Questionnaire-Revised (e.g. emotional, social and vitality domains). For the respiratory muscle strength indices, maximal expiratory pressure at follow up (six to eight weeks post-intervention) was higher in the singing group, mean difference 25.80 (95% confidence interval 5.94 to 45.66). There was no significant difference between groups for any of the other respiratory function parameters (maximal inspiratory pressure, spirometry) at either post-intervention or follow up. AUTHORS' CONCLUSIONS There is insufficient evidence to determine the effects of singing on quality of life or on the respiratory parameters in people with cystic fibrosis. However, there is growing interest in non-medical treatments for cystic fibrosis and researchers may wish to investigate the impact of this inexpensive therapy on respiratory function and psychosocial well-being further in the future.
Collapse
Affiliation(s)
- J Yoon Irons
- c/o CFGD Group, Alder Hey Children's NHS Foundation Trust, Eaton Road, Liverpool, UK, L12 2AP
| | | | | | | |
Collapse
|
45
|
Cinelli E, Bongianni F, Pantaleo T, Mutolo D. Suppression of the cough reflex by α 2-adrenergic receptor agonists in the rabbit. Physiol Rep 2013; 1:e00122. [PMID: 24400133 PMCID: PMC3871446 DOI: 10.1002/phy2.122] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 09/16/2013] [Accepted: 09/18/2013] [Indexed: 01/26/2023] Open
Abstract
The α2-adrenergic receptor agonist clonidine has been shown to inhibit citric acid-induced cough responses in guinea pigs when administered by aerosol, but not orally. In contrast, oral or inhaled clonidine had no effect on capsaicin-induced cough and reflex bronchoconstriction in humans. In addition, intravenous administration of clonidine has been shown to depress fentanyl-induced cough in humans. We investigated the effects of the α2-adrenergic receptor agonists, clonidine and tizanidine, on cough responses induced by mechanical and chemical (citric acid) stimulation of the tracheobronchial tree. Drugs were microinjected (30–50 nL) into the caudal nucleus tractus solitarii (cNTS) and the caudal ventral respiratory group (cVRG) as well as administered intravenously in pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Bilateral microinjections of clonidine into the cNTS or the cVRG reduced cough responses at 0.5 mmol/L and abolished the cough reflex at 5 mmol/L. Bilateral microinjections of 0.5 mmol/L tizanidine into the cNTS completely suppressed cough responses, whereas bilateral microinjections of 5 mmol/L into the cVRG only caused mild reductions in them. Depressant effects on the cough reflex of clonidine and tizanidine were completely reverted by microinjections of 10 mmol/L yohimbine. Intravenous administration of clonidine (80–120 μg/kg) or tizanidine (150–300 μg/kg) strongly reduced or completely suppressed cough responses. These effects were reverted by intravenous administration of yohimbine (300 μg/kg). The results demonstrate that activation of α2-adrenergic receptors in the rabbit exerts potent inhibitory effects on the central mechanism generating the cough motor pattern with a clear action at the level of the cNTS and the cVRG.
Collapse
Affiliation(s)
- Elenia Cinelli
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze Viale G.B. Morgagni 63, 50134, Firenze, Italy
| | - Fulvia Bongianni
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze Viale G.B. Morgagni 63, 50134, Firenze, Italy
| | - Tito Pantaleo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze Viale G.B. Morgagni 63, 50134, Firenze, Italy
| | - Donatella Mutolo
- Dipartimento di Medicina Sperimentale e Clinica, Sezione Scienze Fisiologiche, Università degli Studi di Firenze Viale G.B. Morgagni 63, 50134, Firenze, Italy
| |
Collapse
|
46
|
Poussel M, Bosser G, Varechova S, Demoulin B, Chalon B, Ruckebusch O, Tiotiu A, Renaud P, Schweitzer C, Chenuel B. Desensitization of the cough reflex during limb muscle contraction in anesthetized rabbits. Pulm Pharmacol Ther 2013; 27:96-101. [PMID: 23891778 DOI: 10.1016/j.pupt.2013.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/10/2013] [Accepted: 07/15/2013] [Indexed: 11/19/2022]
Abstract
The 'cough network' exhibits plasticity at the sensor and integration levels leading to modulation of the strength or pattern of the cough reflex. Little is known about the interactions between cough and human activities, especially during exercise. The present study was designed to determine whether exercise, mimicked by electrically induced muscle contractions, can modify the incidence and/or strength of cough following mechanical stimulation of the trachea in anesthetized rabbits. Thirteen anesthetized, tracheotomized rabbits were studied by a total of 311 tracheal stimulations: 196 at rest and 115 during exercise. During muscle contractions, the incidence of the cough reflex (CR) decreased and the expiration reflex (ER) increased (p < 0.0001). The sensitivity of the CR and ER both decreased during exercise compared to the sensitivity of the CR at rest (p < 0.02), while the strength of the expulsive response remained unchanged. These results indicate that adjustments occurring during muscle contractions likely downregulate tracheal defensive reflexes in anesthetized rabbits.
Collapse
Affiliation(s)
- Mathias Poussel
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France.
| | - Gilles Bosser
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Silvia Varechova
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Bruno Demoulin
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Bernard Chalon
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Odile Ruckebusch
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Angelica Tiotiu
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Pierre Renaud
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Cyril Schweitzer
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France
| | - Bruno Chenuel
- EA 3450 DevAH - Development, Adaptation and Disadvantage, Cardiorespiratory regulations and motor control, Université de Lorraine, F-54505, France.
| |
Collapse
|
47
|
Abstract
There is now abundant functional and anatomical evidence that autonomic motor pathways represent a highly organized output of the central nervous system. Simplistic notions of antagonistic all-or-none activation of sympathetic or parasympathetic pathways are clearly wrong. Sympathetic or parasympathetic pathways to specific target tissues generally can be activated tonically or phasically, depending on current physiological requirements. For example, at rest, many sympathetic pathways are tonically active, such as those limiting blood flow to the skin, inhibiting gastrointestinal tract motility and secretion, or allowing continence in the urinary bladder. Phasic parasympathetic activity can be seen in lacrimation, salivation or urination. Activity in autonomic motor pathways can be modulated by diverse sensory inputs, including the visual, auditory and vestibular systems, in addition to various functional populations of visceral afferents. Identifying the central pathways responsible for coordinated autonomic activity has made considerable progress, but much more needs to be done.
Collapse
Affiliation(s)
- Ian Gibbins
- Anatomy & Histology; Flinders University; SA Austraila
| |
Collapse
|
48
|
Ferasin L, Crews L, Biller D, Lamb K, Borgarelli M. Risk Factors for Coughing in Dogs with Naturally Acquired Myxomatous Mitral Valve Disease. J Vet Intern Med 2013; 27:286-92. [DOI: 10.1111/jvim.12039] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 10/21/2012] [Accepted: 12/06/2012] [Indexed: 12/01/2022] Open
Affiliation(s)
- L. Ferasin
- Specialist Veterinary Cardiology Consultancy Ltd; Biggin Hill Kent UK
| | - L. Crews
- College of Veterinary Medicine; University of Minnesota; St Paul MN
| | - D.S. Biller
- College of Veterinary Medicine; Kansas State University; Manhattan KS
| | - K.E. Lamb
- Lamb Biostatistical and Scientific Writing Consulting; St Paul MN
| | - M. Borgarelli
- College of Veterinary Medicine; Kansas State University; Manhattan KS
| |
Collapse
|
49
|
Abstract
Traditionally push-button and symptom diaries have been used to document cough events, especially when examining temporal associations between cough and reflux events. More recently, acoustic devices have allowed more accurate recording of cough events, and compared with the latter traditional techniques reported 6-18 times more coughing. Whether the differences reported between these techniques represents disparities in subject groups or cough detection and quantification methods is unknown. In this issue of the American Journal of Gastroenterology, Kavitt et al. show that listeners of such recordings have a 4-fold increase in odds of recording cough events compared with patients using push-button techniques, and that even when using a 5-min window to assess temporal concordance/discordance, over 70% of coughs were not reported by the patients. These observations have potential significant implications when assessing temporal associations between cough and reflux, and thus any clinical decision making based on these data. This editorial examines both the findings of Kavitt et al. and discusses the pitfalls and benefits of validated accurate documentation of cough.
Collapse
|
50
|
Cinelli E, Bongianni F, Pantaleo T, Mutolo D. Modulation of the cough reflex by GABA(A) receptors in the caudal ventral respiratory group of the rabbit. Front Physiol 2012; 3:403. [PMID: 23087651 PMCID: PMC3475209 DOI: 10.3389/fphys.2012.00403] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 10/01/2012] [Indexed: 11/16/2022] Open
Abstract
We have previously shown that the caudal ventral respiratory group (cVRG) is a possible site of action of some antitussive drugs and plays a crucial role in determining both the expiratory and inspiratory components of the cough motor pattern. In addition, it has been reported that medullary expiratory neurons of the cVRG are subject to potent GABAergic gain modulation. This study was devoted to investigate the role of cVRG GABAA receptors in the control of baseline respiratory activity and cough responses to mechanical and chemical (citric acid) stimulation of the tracheobronchial tree. To this purpose, bilateral microinjections (30–50 nl) of bicuculline or muscimol were performed into the cVRG of pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Bicuculline (1 mM) increased peak abdominal activity and respiratory frequency due to decreases in TE. Cough responses were potentiated mainly owing to increases in the cough number. The recovery was observed within ~2 h. On the contrary, muscimol (0.3 mM) abolished abdominal activity and decreased respiratory frequency due to increases in TE. In addition, cough responses were progressively reduced and completely suppressed within ~20 min. Partial recovery of cough responses was achieved after ~3 h or within ~5 min following bicuculline microinjections at the same locations. The sneeze reflex induced by mechanical stimulation of the nasal mucosa persisted following bicuculline and muscimol microinjections. However, the number and intensity of expiratory thrusts were enhanced by bicuculline and suppressed by muscimol. The results provide evidence that a potent GABAA-mediated inhibitory modulation is exerted at the level of the cVRG not only on respiratory activity, but also on cough and sneeze reflex responses.
Collapse
Affiliation(s)
- Elenia Cinelli
- Dipartimento di Scienze Fisiologiche, Università degli Studi di Firenze Firenze, Italy
| | | | | | | |
Collapse
|