Cough Flashcards
Describe the afferent pathway of cough
Cough reflex arc of vagus nerve, regulated by rapidly adapting receptors (RARs), slowly adapting receptors (SARs), and C-fibers. Cough can be stimulated at any level of the vagus nerve (ear to esophagus)
Describe the efferent pathway of cough
1) Inspiratory phase- inhalation before glottis closure
2) Compression phase- thoracic and abdominal contraction against fixed diaphragm (large pressure generation)
3) Expiratory phase- glottis opens for rapid air expulsion
4) Relaxation phase- chest wall and abdomen relax
What i the cough reflex not effective?
Under general anesthesia, sedation, intoxication, certain medications (narcotics), NM diseases, inability to close glottis
What are the complications for ineffective cough?
Pneumonia (uncleared secretions), high intrathoracic pressure, decreased quality of life.
What is the function of cough?
To clear secretions, pathogens, particulates, and foreign bodies from the lungs, larynx, and pharynx.
What are the three classifications of cough?
Acute- less than 3 weeks
Subacute- 3-8 weeks
Chronic- more than 8 weeks
What are the most common causes of acute cough?
URI, acute bronchitis, condition exacerbation, and exposure
What are the most common causes of chronic cough?
Upper airway cough syndrome, asthma, GERD, non-asthmatic eosinophilic bronchitis, hypersensitivity (neuropathic cough)
What is the presentation of UACS?
“tickle in throat”, throat clearing, hoarseness, nasal congestion, drainage.
PE: posterior cobblestoning, pharynx mucus
How do you treat UACS?
Antihistamine and decongestant for 2 weeks.
What is the presentation of GERD?
Cough, some heartburn or regurgitation. No exam findings.
How do you treat GERD?
Gastric acid suppression (proton pump inhibitor, diet/lifestyle) for 2 months
What is the presentation of NAEB?
Cough without wheezing or dyspnea, no findings.
How do you treat NAEB?
Inhaled corticosteroids for 4 weeks
How is chronic cough different in children?
Defined as more than 4 weeks, caused by asthma, sinusitis, GERD, foreign body and CF.
