For educational purposes only
Approach to Management of Cough
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PP-NXM-IND-0261 30th Apr 2019
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Outline
Definition and Classification of Cough
Assessment of Cough
Acute Cough
Subacute Cough
Chronic Cough
Take Home Messages
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Definitions
Cough
•Cough is a forced expulsive maneuver, usually against a closed glottis and which is associated with a characteristic sound
•Cough frequently presents as a troublesome symptom to clinicians working in both primary and secondary care
Acute cough
•Acute cough is defined as one lasting less than 3 weeks
• It is most commonly associated with viral upper respiratory tract infection
• In the absence of significant co-morbidity, an acute cough is normally benign and self-limiting
Chronic Cough
•Chronic cough is defined as one lasting more than 8 weeks
•Most patients present with a dry or minimally productive cough
•The presence of significant sputum production usually indicates primary lung pathology
• In chronic cough a heightened cough reflex is the primary abnormality
Morice AH, McGarvey L, Pavord I. Recommendations for the management of cough in adults. Thorax. 2006 Sep 1;61(suppl 1):i1-24.
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Classification of Cough: Duration and Pattern
Duration1
Acute<3 weeks
Subacute3–8-weeks
Chronic> 8 weeks
Pattern of CoughCommon Triggers2
Taking a deep breath
Talking over the telephone
Changes in temperature of inhaled air Eating crumbly food
Particular smells or perfumes
Lying in a supine posture
Laughing
1. Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..2. Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.
For educational purposes only
Analysis of Cough Severity
Clinical historyCough symptom
scoreCough-specific quality of life
Ambulatory cough counts
Ambulatory cough intensity
Spectral analysis of cough sounds
Cough sensitivity (to capsaicin or
citric acid)
Estimating the duration of cough is the first step in narrowing the list of possible diagnoses 1
1. Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..2. Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.
For educational purposes only
Potential Complications of Cough
Acute cervical radiculopathy, cerebral air embolism,
cerebral spinal fluid rhinorrhea
Neurological
Asthma exacerbation, herniation of the lung, laryngeal trauma
Respiratory system
Rib fractures, intercostal muscle rupture
Musculoskeletal system
Urinary incontinence
Genitourinary system
Arterial hypotension, bradyarrhythmia, tachyarrhythmia
Cardiovascular system
Gastroesophageal reflux events, inguinal hernia,
splenic rupture
Gastrointestinal system
Lifestyle changes, self-consciousness, fear of serious disease
Miscellaneous
Irwin RS. Complications of cough: ACCP evidence-based clinical practice guidelines. Chest. 2006 Jan 1;129(1):54S-8S.
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Assessment of Cough
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Clinical Assessment of an Adult with Cough
History (Including questions regarding the following)
• Duration, characteristics, associated symptoms and timing of cough
• Sputum production
• Smoking history- There is a threefold greater prevalence of cough among smokers compared to non smokers
• Occupational history
Physical examination: May demonstrate clinical signs of obstructive lung disease, lung cancer, pulmonary fibrosis, etc.
• Acute cough: Dullness on percussion, bronchial breathing and crackles on auscultation
• Chronic cough: An ear, nose and throat (ENT) examination may reveal evidence of nasal obstruction due to inflamed turbinates or the presence of polyps. The appearance of secretions draining in the posterior pharynx may be apparent
Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.
For educational purposes only
Clinical Assessment of an Adult with Cough
Chest radiograph
• A chest radiograph is mandatory at an early stage as a significant abnormality will alter the diagnostic algorithm and avoid unnecessary investigation
Spirometry and peak expiratory flow measurements
• When available, spirometry both before and after an inhaled bronchodilator should be performed at an early stage in the routine testing of all patients with cough
Sinus imaging
• A plain radiograph of the sinuses may reveal evidence of opacity, mucosal thickening and air–fluid levels in individuals with sinusitis but is rather less helpful when rhinitis is the prominent element
Fiber-optic bronchoscopy
• Fibreoptic bronchoscopy together with a chest radiograph are the first tests to consider in evaluating a smoker with cough. However, the diagnostic yield from bronchoscopy in the routine evaluation of chronic cough is low
Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.
Clinical assessment involves an evaluation of the severity of cough in terms of its frequency and intensity and any impact on psychological well-being
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Evaluations for Chronic Cough
Investigation Comment
Chest radiograph Essential investigation in all patients
Spirometry and reversibility testing A baseline investigation; not readily available in primary care
Peak flow recording May reliably demonstrate diurnal variability
Bronchial challenge A negative study effectively rules out asthma but not steroid responsive cough
24-h ambulatory pH monitoring If available; helpful in patients with no reflux symptoms to assess duration and frequency of reflux episodes and any temporal association with cough
Paranasal sinus radiograph (or CT scan)
May reveal sinus opacity, mucosal thickening and air–fluid levels
Non-invasive assessment of airway inflammation
Induced sputum useful in identifying an eosinophilic bronchitis; best reserved for patients with negative broncho-provocation test
Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.
For educational purposes only
Acute Cough
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Acute Cough
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
Acute cough can be the presenting manifestation of pneumonia, left ventricular failure, asthma, or conditions that predispose patients to the aspiration of foreign matter
In the absence of any treatment, the prevalence of cough due to the common cold ranges from 83% within the first 48
hours of the cold to 26% on day 14
Viral infections of the upper respiratory tract are the most common causes of acute cough
Cough appears to arise from the stimulation of the cough reflex in the upper respiratory tract by postnasal drip or clearing of the throat
For educational purposes only
Acute Cough
In the absence of chronic obstructive pulmonary disease, the failure to diagnose bronchitis when present will not adversely affect the patient, because most acute respiratory infections are viral
The common cold is diagnosed when patients with an acute respiratory illness are characterized by symptoms and signs related primarily to the nasal passages(e.g., rhinorrhea, sneezing, nasal obstruction, and postnasal drip), with or without fever, lacrimation, and irritation of the throat, and when a chest examination is normal
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
LRTI: lower respiratory tract infection; PE: pulmonary embolism; UACS: upper airway cough syndrome; URI: upper respiratory tract infection;COPD: Chronic obstructive pulmonary disorder
Acute cough
History and physical examination, environmental and occupational factors,
travel exposures + investigations
Non-life-threatening
diagnosis
Life-threatening
diagnosis
InfectiousExacerbation of pre-
existing condition
Asthma
Bronchiectasis
UACS COPD
Other
LRTI URTI
PertussisAcute bronchitis
Consider TB in endemic areas
or high risk
Pneumonia, severe exacerbation of asthma or
COPD, PE, heart failure, other serious disease
Evaluate and treat
first
Red flags
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
Important Reminders and Red Flags
• Check for red flags
• Routinely assess cough quality of life or cough severity with validated tool
• Routinely follow up with patient in 4-6 weeks
Reminders
• Hemoptysis• Smoker > 45 years of age with a new cough, change in cough, or
coexisting voice disturbance• Adults aged 55-80 years who have a 30 pack-year smoking history
and currently smoke or who have quit within the past 15 years• Prominent dyspnea, especially at rest or at night• Hoarseness • Systemic symptoms :
• Fever• Weight loss • Peripheral Edema with weight gain
• Trouble swallowing when eating or drinking• Vomiting• Recurrent pneumonia• Abnormal respiratory exam and/or abnormal chest radiograph
coinciding with duration of cough
Red flags
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
COPD: Chronic obstructive pulmonary disease
Indications for further investigations1,2
• Inadequate response to optimal treatment
• Hemoptysis• Systemic illness• Suspicion of inhaled
foreign body• Suspicion of lung cancer
Chest radiography and spirometry remain baseline investigations in the diagnosis of cough1
Bronchoscopy Methacholinechallenge test
Sinus imaging24-h esophageal pH
monitoring
Indications for Further Investigations in Cough
1. McGarvey LP. Cough• 6: Which investigations are most useful in the diagnosis of chronic cough?. Thorax. 2004 Apr 1;59(4):342-6.2. Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
British Thoracic Society Guidelines– Acute Cough
Morice AH, McGarvey L, Pavord I. Recommendations for the management of cough in adults. Thorax. 2006 Sep 1;61(suppl 1):i1-24.
Acute viral cough is almost invariably benign and prescribed treatment can be regarded as unnecessary
Acute viral cough can be distressing and cause significant morbidity
Patients report benefit from various over-the-counter preparations but there is little evidence of a specific pharmacological effect
The simplest and cheapest advice may be to provide a ‘‘home remedy’’ such as honey and lemon
Central modulation of the cough reflex is common; simple voluntary suppression of cough may be sufficient to reduce cough frequency
Opiate antitussives have a significant adverse side effect profile and are not recommended
For educational purposes only
British Thoracic Society Guidelines – Acute Cough Pharmacotherapy
Morice AH, McGarvey L, Pavord I. Recommendations for the management of cough in adults. Thorax. 2006 Sep 1;61(suppl 1):i1-24.
• Non-sedating opiate which is a component of many over-the-counter cough remedies
• The general recommended dosage is probably sub-therapeutic
• There is a dose response, and maximum cough reflex suppression occurs at 60 mg and can be prolonged
Dextromethorphan
• Menthol by inhalation suppresses the cough reflex and may be prescribed as menthol crystals BPC or in the form of proprietary capsules
• Cough suppression is acute and short lived
Menthol
• First generation antihistamines with sedative properties suppress cough but also cause drowsiness. They may be a suitable treatment for nocturnal cough
Sedative antihistamines
• These opiate antitussives have no greater efficacy than dextromethorphan but have a much greater adverse side effect profile and are not recommended
Codeine
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Subacute Cough
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Subacute Cough
• When cough is subacute and not associated with an obvious respiratory infection, evaluate patients in the same way as those with chronic cough
• For a cough that began with an upper respiratory tract infection and has lasted for 3 to 8 weeks, the most common conditions to consider are post-infectious cough, bacterial sinusitis, and asthma
• When a patient presents with wheezes, rhonchi, or crackles on physical examination, a chest radiograph should be obtained
Post-infectious cough: Cough that begins with an acute respiratory tract infection that is not complicated by pneumonia (i.e., the chest radiograph is normal) and that ultimately resolves without treatment. It may result from postnasal drip or clearing of the throat due to rhinitis,
tracheobronchitis, or both, with or without transient bronchial hyper-responsiveness
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
UACS: upper airway cough syndrome; AECB: acute exacerbation of chronic bronchitis; GERD: gastroesophageal reflux disease; NAEB: non-asthmatic eosinophilic bronchitis; COPD: Chronic obstructive pulmonary disorder
Sub-Acute cough
History and physical examination, environmental and occupational factors,
travel exposures + ask about red flags
Not post infectious
New onset or exacerbation of pre-existing condition
Consider TB in endemic areas or
high risk
Pneumonia, severe exacerbation of
asthma or COPD, PE, heart failure, other
serious disease
Evaluate and treat
first
Workup same as chronic
cough
Post infectious or life
threatening diagnosis
Asthma
Bronchiectasis
UACS
Other
Bronchitis
GERD
NAEBAECB/COPDPertussis
TB Post-infection
COPD
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
Important Reminders and Red Flags
• Check for red flags
• Routinely assess cough quality of life or cough severity with validated tool
• Routinely follow up with patient in 4-6 weeks
Reminders
• Hemoptysis• Smoker > 45 years of age with a new cough, change in cough, or
coexisting voice disturbance• Adults aged 55-80 years who have a 30 pack-year smoking history
and currently smoke or who have quit within the past 15 years• Prominent dyspnea, especially at rest or at night• Hoarseness • Systemic symptoms :
• Fever• Weight loss • Peripheral Edema with weight gain
• Trouble swallowing when eating or drinking• Vomiting• Recurrent pneumonia• Abnormal respiratory exam and/or abnormal chest radiograph
coinciding with duration of cough
Red flags
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
Chronic Cough
For educational purposes only
Chronic Cough
Chronic cough can result simultaneously from more than one condition (as is the case in 18 to 93% of instances),
therefore therapy that is partially successful should not be stopped but should instead be sequentially supplemented
Recommendation for evaluation of chronic cough: A systematic evaluation that initially assesses the most common causes by means of trials of empirical therapy and trials involving the avoidance of irritants and drugs, along with focused laboratory testing (e.g., chest radiography or methacholine challenge), and if required, additional testing and consultation with a specialist
The definitive diagnosis of the cause of chronic cough is established on the basis of an observation of which specific therapy eliminates the cough
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
Clinical Evaluation of Chronic Cough
Review the patient’s history and do a physical examination and
focus on the most common causes of chronic cough (i.e.,
postnasal-drip syndromes, asthma, and gastroesophageal
reflux disease)
Obtain a chest radiograph. Determine whether the symptoms
conform to the clinical profile that is usually associated with a diagnosis
of postnasal-drip syndrome, asthma, gastroesophageal reflux disease or eosinophilic bronchitis, alone or in
combination
If the cough is productive of blood, evaluate according to
published guidelines for hemoptysis
If the patient has a history of smoking or of exposure to other
environmental irritants or is currently being treated with an angiotensin-converting–enzyme inhibitor, eliminate the irritant or discontinue the drug for 4 weeks
In the absence of exposure to irritants, a diagnosis of chronic bronchitis is untenable even if
the cough is productive
A definitive diagnosis can be made only when cough responds
to specific therapy
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
Common Causes of Chronic Cough
Postnasal drip syndrome is the most
common cause of chronic cough
The outcome of specific therapy will depend on
the determination of the correct cause and the choice of the correct
specific therapy
The differential diagnosis of postnasal-drip syndrome includes sinusitis and the following types of rhinitis,
alone or in combination: non-allergic, allergic, post-
infectious, vasomotor, drug-induced, and environmental-
irritant–induced
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
UACS: upper airway cough syndrome; AECB: acute exacerbation of chronic bronchitis; NAEB: non-asthmatic eosinophilic bronchitis; COPD: Chronic obstructive pulmonary disorder; ACEI: angiotensin-converting enzyme inhibitor; A/D: antihistamine/decongestant; BD: bronchodilator; HRCT: high-resolution CT; ICS: inhaled corticosteroid; LTRA: leukotriene antagonist; PPI: proton pump inhibitor
Chronic cough
History to include red flags, environmental and occupational factors, travel exposuresPhysical exam and chest radiograph
Smoking, ACEI,
Sitagliptin
Investigate and treat
Discontinue for at least 4
weeks
A cause of cough is suggested or concern for life threatening condition
4 most common causes to consider:1. Upper Airway Cough Syndrome (UACS) secondary to rhinosinus diseasesConsider: • Sinus imaging• Naso-pharyngoscopy• Allergy evaluation or empiric treatment2. AsthmaIdeally evaluate:• Spirometry• Bronchodilator reversibility• Broncho-provocation challenge• Allergy evaluation or empiric treatment
3. Non-asthmatic Eosinophilic Bronchitis (NAEB)Ideally evaluate:• Sputum eosinophilia• Fraction exhaled nitric oxide (FENO)• Allergy evaluation or empiric treatment4. Gastroesophageal Reflux Disease (GERD)Physiologic testing for refractory patients Initial treatment to include:• More than acid suppression
No response at 4-6 week
follow up
Initial treatments:• UACS: A/D• Asthma – ICS, BD, LTRA, trigger avoidance• NAEB – ICS, Trigger avoidance• GERD – PPI, diet/lifestyle changes (Treatment of GERD should not be limited to acid suppression
Inadequate response to optimal treatment, follow up 4-6 weeks
Inadequate response to optimal treatment, follow up 4-6 weeks
Further investigations (next slide)
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
Reminders and Further Investigations
• Check for red flags and address them
• Optimize therapy for each diagnosis
• Check compliance during regularly scheduled and frequent follow ups (assess for patient barriers to enactment or receipt of instructions)
• Due to the possibility of multiple causes, maintain all partialIy effective treatment
• Routinely assess for environmental and occupational factors
• Routinely assess cough severity & quality of life with validated tools
• Routinely follow up with patient in 4-6 weeks
• Consider a referral to a Cough Clinic for refractory cough
Reminders
• UACS: A/D• Asthma – ICS, BD, LTRA, trigger avoidance• NAEB – ICS, Trigger avoidance• GERD – PPI, diet/lifestyle changes (Treatment of GERD should not be limited to acid suppression
Further investigations
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
Red flags for Chronic Cough
• Hemoptysis• Smoker > 45 years of age with a new cough, change in cough, or
coexisting voice disturbance• Adults aged 55-80 years who have a 30 pack-year smoking history
and currently smoke or who have quit within the past 15 years• Prominent dyspnea, especially at rest or at night• Hoarseness • Systemic symptoms :
• Fever• Weight loss • Peripheral Edema with weight gain
• Trouble swallowing when eating or drinking• Vomiting• Recurrent pneumonia• Abnormal respiratory exam and/or abnormal chest radiograph
coinciding with duration of cough
Red flags
Irwin RS, French CL, Chang AB, Altman KW, Adams TM, Azoulay E, Barker AF, Birring SS, Blackhall F, Bolser DC, Boulet LP. Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report. Chest. 2018 Jan 1;153(1):196-209.
For educational purposes only
British Thoracic Society Guidelines – Chronic Cough
Morice AH, McGarvey L, Pavord I. Recommendations for the management of cough in adults. Thorax. 2006 Sep 1;61(suppl 1):i1-24.
One of the commonest causes of persistent cough is smoking, which appears to be dose related. Patients often state that their cough changes in character with smoking cessation
A chest radiograph should be undertaken in all patients with chronic cough and those with acute cough demonstrating atypical symptoms
Note all medications, particularly ACE inhibitors, and consider which might be causing or potentiating the cough. The cough may take some months to settle following withdrawal of ACE inhibitors
Chronic cough is a common association of respiratory diseases and a thorough respiratory history should be sought
Interpretation of the diagnostic characteristics of the cough should be done with caution
Chronic cough is more likely to occur in middle aged women
For educational purposes only
Pitfalls in Managing Chronic Cough
Asthma
• Failure to recognize it as a syndrome ofcough and phlegm
• Failure to recognize that inhaled medicationsmay exacerbate cough
• Assuming a positive result of methacholinechallenge alone is diagnostic of asthma
Post nasal drip
• Failure to recognize it as a syndrome of cough and phlegm
• Assuming all H1 antagonists are the same• Failure to consider sinusitis (being not obvious)• Failure to consider allergic rhinitis and
recommend avoidance of allergens (as symptoms are perennial)
GERD
• Failure to recognize it as a syndrome of cough and phlegm
• Assuming that cough cannot be due to GERD because it remains unchanged when GI symptoms improve
• Failure to recognize effects of co-existing diseases or their treatment
• Failure to adequately treat co-existing causes of cough that perpetuate the cycle of cough
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..
For educational purposes only
Take Home Messages
• Cough is a symptom with many facets: a protective mechanism for the lungs, a warning sign of disease, and a detrimental symptom when persistent
• It is one of the most common symptoms for which patients seek medical attention from primary care physicians and pulmonologists
• Viral infections of the upper respiratory tract are the most common causes of acute cough
• Nearly all conditions affecting the respiratory system may cause cough, but to the physician it is most important to exclude the most serious conditions that need prompt treatment
• With a systematic approach based on guidelines, it should be possible to diagnose and treat cough successfully in the majority of cases
• Chronic cough is a common association of respiratory diseases and a thorough respiratory history should be sought
Irwin RS, Madison JM. The diagnosis and treatment of cough. New England Journal of Medicine. 2000 Dec 7;343(23):1715-21..Chung KF, Widdicombe JG, Boushey HA, editors. Cough: causes, mechanisms and therapy. John Wiley & Sons; 2008 Apr 15.Morice AH, McGarvey L, Pavord I. Recommendations for the management of cough in adults. Thorax. 2006 Sep 1;61(suppl 1):i1-24.McGarvey LP. Cough• 6: Which investigations are most useful in the diagnosis of chronic cough?. Thorax. 2004 Apr 1;59(4):342-6.