Moving on
Margaret Cromarty, Derick Wade in Stroke – It Couldn’t Happen to Me, 2018
Coughing was a tremendous problem for many months following the stroke and, to a lesser extent, still is. Of course there are those who would not regard it as such. A strong cough reflex helps to protect the airway – that being a most important consideration, and an obsession of anaesthetists, physiotherapists, speech therapists and nurses. To me, the cough was a real trial; causing discomfort, worry and, worst of all for me, embarrassment. It was ironic that, paralysed as I was, involuntary actions such as coughing, yawning or sneezing could provoke quite big movements. Coughing would often send me bouncing across the bed and, not infrequently, leave me perilously close to, or just over, the edge. There I would hang, strangely enough not panicking, waiting patiently to be rescued. Someone would eventually notice my predicament and straighten me up.
Cough In Children
Michael B O’Neill, Michelle Mary Mcevoy, Alf J Nicholson, Terence Stephenson, Stephanie Ryan in Diagnosing and Treating Common Problems in Paediatrics, 2017
The mechanism of cough is as follows: after an initial rapid inspiration, a forced expiration against a closed glottis occurs, at which time the glottis opens with a simultaneous respiratory effort that involves contracture of the diaphragm and muscles of the abdominal wall, and as a consequence a blast of rapidly moving air expels air and any movable substance from the trachea. Cough is primarily a protective reflex; it enhances mucociliary clearance, aids clearance of excessive secretions and airway debris from the respiratory tract. Cough receptors are located in the larynx to the bronchial tree and the cough reflex is mediated through the vagus nerve in the afferent pathway, to the brainstem with cortical modulation and the motor pathway is to the respiratory muscles. The cough reflex can be sensitised by viral respiratory tract infections, asthma, gastro-oesophageal reflux and through medication, e.g. angiotensin-converting enzyme inhibitors. Children who are less than 5 years of age normally do not expectorate sputum when they cough, which influences the physician’s diagnostic approach.
Pulmonary – Treatable traits
Vibeke Backer, Peter G. Gibson, Ian D. Pavord in The Asthmas, 2023
Cough is an important airway defence mechanism mediated by a neuro-immune interaction. A dysregulation of either or both of the airway immune or nervous system could lead to an altered (frequently increased) cough reflex sensitivity and increased coughing. Up to 10% of patients presenting to secondary care in the United Kingdom do so because of a cough lasting more than 8 weeks (chronic cough) and 75% of us will, at some time in our life, present to primary because of a prolonged cough. Chronic cough is particularly prevalent in middle-aged females. Cough associated with corticosteroid responsive type-2 airway inflammation is present in only 12% of patients, and when present, is often associated with normal airway responsiveness (eosinophilic bronchitis). Despite this, many patients are treated with inhalers on the assumption that they have cough variant asthma or eosinophilic bronchitis.
Emerging drugs in the treatment of chronic cough
Published in Expert Opinion on Emerging Drugs, 2023
Danica Brister, Mustafaa Wahab, Moaaz Rashad, Nermin Diab, Martin Kolb, Imran Satia
The involuntary cough reflex is designed to protect against aspiration of food, foreign bodies and prevent the inhalation of noxious gases. It can be triggered by stimulation of peripheral receptors of vagal nerve fibers innervating the larynx, upper and lower airways. There are at least two known subtypes of vagal nerve afferents involved in the cough reflex response; myelinated A fibers which originate in the nodose ganglion, and the slower, unmyelinated C-fibers of the jugular ganglion (Figure 1) [50,51]. A fibers are predominantly mechanosensitive, whilst C-fibers are activated by chemical and temperature triggers and will respond to flavors and fragrances such as capsaicin, garlic, cinnamaldehyde, and methanol [51–53]. Multiple receptor subtypes have been identified on these afferent fibers, including ligand gated ion channels (LGIC), and G protein coupled receptors. LGIC include transient receptor protein (TRP) vanilloid 1 (TRPV1), TRP ankyrin 1 (TRPA1), and TRP melastin 8 (TRPM8) can be found on both alpha-delta and c-fibers [50,52]. Purinergic receptors, such as P2×3, are activated by extracellular ATP release in response to cellular injury and within the upper airway are expressed on C-fibers of the jugular ganglion [10]. Patients with RCC/UCC demonstrate a heightened response to capsaicin inhalation compared to healthy controls, which may be mediated by more peripheral receptors, the or the sensitization of peripheral nerves [10].
Impact of capsaicin concentration evoking coughs on clinical variables in patients with asthma
Published in Experimental Lung Research, 2021
Kyung-Hun Park, Byeong-Gon Kim, Preun-Haneul Lee, Jisu Hong, Junehyuck Lee, Sung-Woo Park, Do-Jin Kim, An-Soo Jang
Asthma affects an estimated 300 million persons worldwide and is characterized by symptoms including cough, wheeze, chest tightness, and shortness of breath.1 The hallmarks of asthma are bronchial hyper-responsiveness, variable airflow obstruction, and airway inflammation.2 Chronic cough is among the most common symptoms of patients with asthma and may be the primary presenting feature of asthma in the absence of dyspnea and wheezing.3 Airway diseases such as asthma are associated with excessive coughing. Cough in asthmatic patients is not only common and troublesome but also predicts disease severity and poor prognosis, suggesting that it reflects important pathophysiologic processes4,5; however, remarkably little is understood of the underlying mechanisms. The general assumption is that airway afferent nerves activating the cough reflex are stimulated by inflammatory mediators, mucus, and bronchospasm. The extent to which these phenomena may be a consequence of increased activation of vagal afferents by pathology in the airways or an altered neuronal phenotype is unknown.6
Carob extract attenuates brain and lung injury in rats exposed to waterpipe smoke
Published in Egyptian Journal of Basic and Applied Sciences, 2018
Mona Abdel-Rahman, Amira A. Bauomy, Fatma Elzahraa H. Salem, Mona Ahmed Khalifa
The waterpipe smokers had increased cough and biologic abnormalities in several anatomic components in the lung compared to nonsmokers [35]. The cough reflex can be initiated by a wide variety of stimuli [36]. The vagal fibers for cough enter the brainstem (cough center) and relay in the nucleus of the solitary tract with connections to second-order neurons [37,38] . Afferent impulses travel to the dorsal medulla where the reflex is subject to cortical control where cerebral cortex has a role in influencing cough. The brain then sends signals back to the lungs and respiratory muscles [39,40] . Neurotransmitters which involved in the central cough complex are tachykinins, glutamate, g-aminobutyric acid, N-methyl-D-aspartate, 5-HT and DA [37,38,41] . Increased release of substance P is involved in the development of cough and inflammation of the airway, and its production is regulated by dopaminergic neurons in the brainstem.
Related Knowledge Centers
- Bronchiole
- Bronchus
- Cough
- Epithelium
- Respiratory Tract
- Trachea
- Lung
- Larynx
- Carina of Trachea
- Pulmonary Alveolus