• Cough can be initiated by• 1)airway irritants, which enter the

tracheobronchial tree by inhalation (smoke, dust, fumes) or

• 2)by aspiration (upper airway secretions, gastric contents, foreign bodies

• 3)Additionally, prolonged exposure to such irritants may initiate airway inflammation, which can itself trigger cough and sensitize the airway to other irritants

• inflammation, constriction, infiltration, or compression of airways can be associated with cough.

• Inflammation commonly results from airway infections, ranging from viral or bacterial bronchitis to bronchiectasis.

• Asthma is a common cause of cough• A neoplasm infiltrating the airway wall,

such as bronchogenic carcinoma or a carcinoid tumor, is commonly associated with cough.

• Airway infiltration with granulomas may also trigger a cough, as seen with endobronchial sarcoidosis or tuberculosis.

• Compression of airways results from extrinsic masses, including lymph nodes, mediastinal tumors, and aortic aneurysms.

• Examples of parenchymal lung disease potentially producing cough include interstitial lung disease, pneumonia, and lung abscess.

• Congestive heart failure may be associated with cough, probably as a consequence of interstitial as well as peribronchial edema.

• A nonproductive cough complicates the use of angiotensin-converting enzyme (ACE) inhibitors

• Although the mechanism is not known with certainty, it may relate to accumulation of bradykinin or substance P, both of which are degraded by ACE

• Coughing may be initiated either voluntarily or reflexively. As a defensive reflex it has both afferent and efferent pathways.

• The afferent limb includes receptors within the sensory distribution of the trigeminal, glossopharyngeal, superior laryngeal, and vagus nerves.

• The efferent limb includes the recurrent laryngeal nerve and the spinal nerves.

• The cough starts with a deep inspiration followed by glottic closure, relaxation of the diaphragm, and muscle contraction against a closed glottis. The resulting markedly positive intrathoracic pressure causes narrowing of the trachea.

• Once the glottis opens, the large pressure differential between the airways and the atmosphere coupled with tracheal narrowing produces rapid flow rates through the trachea. The shearing forces that develop aid in the elimination of mucus and foreign materials.

• 1. Is the cough acute or chronic?

• 2. At its onset, were there associated symptoms suggestive of a respiratory infection?

• 3. Is it seasonal or associated with wheezing?

• 4. Is it associated with symptoms suggestive of postnasal drip (nasal discharge, frequent throat clearing, a "tickle in the throat") or gastroesophageal reflux (heartburn or sensation of regurgitation)? (

• 5. Is it associated with fever or sputum? If sputum is present, what is its character?

• 6. Does the patient have any associated diseases or risk factors for disease (e.g., cigarette smoking, risk factors for infection with HIV, environmental exposures)?

• 7. Is the patient taking an ACE inhibitor?

• Chest radiography• Pulmonary function testing • If sputum is produced, gross and

microscopic examination may provide useful information. Purulent sputum suggests chronic bronchitis, bronchiectasis, pneumonia, or lung abscess.

• Fiberoptic bronchoscopy is the procedure of choice for visualizing an endobronchial tumor and collecting cytologic and histologic specimens.

• . High-resolution computed tomography (HRCT) can confirm the presence of interstitial disease

• Common complications of coughing include chest and abdominal wall soreness,

• urinary incontinence, and exhaustion.• paroxysms of coughing may precipitate

syncope • . Although cough fractures of the ribs

may occur in otherwise normal patie

• Definitive treatment of cough depends on determining the underlying cause and then initiating specific therapy.

• Symptomatic or nonspecific therapy of cough should be considered when:

• (1) the cause of the cough is not known or specific treatment is not possible, and

• (2) the cough performs no useful function or causes marked discomfort.

• Hemoptysis is defined as the expectoration of blood from the respiratory tract,

• . Massive hemoptysis is variably defined as the expectoration of >100 to >600 mL over a 24-h period, although the patient's estimation of the amount of blood is notoriously unreliable.

• Expectoration of even relatively small amounts of blood is a frightening symptom and can be a marker for potentially serious disease, such as bronchogenic carcinoma.

• Massive hemoptysis, on the other hand, can represent an acutely life-threatening problem. Large amounts of blood can fill the airways and the alveolar spaces, not only seriously disturbing gas exchange but potentially causing the patient to suffocate.

• Tracheobronchial source

• Neoplasm (bronchogenic carcinoma, endobronchial metastatic tumor, Kaposi's sarcoma, bronchial carcinoid)

• Bronchitis (acute or chronic)

• Bronchiectasis• Broncholithiasis• Airway trauma• Foreign body

• LUNG parenchymal source

• Lung abscess• Pneumonia• Tuberculosis• Mycetoma ("fungus

ball")• Goodpasture's

syndrome• Idiopathic pulmonary

hemosiderosis• Wegener's

granulomatosis• Lupus pneumonitis• Lung contusion

• Primary vascular source

• Arteriovenous malformation

• Pulmonary embolism• Elevated pulmonary

venous pressure (esp. mitral stenosis)

• Miscellaneous/rare causes

• Pulmonary endometriosis

• Systemic coagulopathy or use of anticoagulants or thrombolytic agents

• Source other than the lower respiratory tract

• Upper airway (nasopharyngeal) bleeding

• Gastrointestinal bleeding

• . Hemoptysis that is described as blood-streaking of mucopurulent or purulent sputum often suggests bronchitis.

• Chronic production of sputum with a recent change in quantity or appearance favors an acute exacerbation of chronic bronchitis.

• Fever or chills accompanying blood-streaked purulent sputum suggests pneumonia, whereas a putrid smell to the sputum raises the possibility of lung abscess.

• When sputum production has been chronic and copious, the diagnosis of bronchiectasis should be considered.

• Hemoptysis following the acute onset of pleuritic chest pain and dyspnea is suggestive of pulmonary embolism.

• A history of previous or coexisting disorders should be sought, such as renal disease (seen with Goodpasture's syndrome or Wegener's granulomatosis), lupus erythematosus (with associated pulmonary hemorrhage from lupus pneumonitis), or a previous malignancy (either recurrent lung cancer or endobronchial metastasis from a nonpulmonary primary tumor).

• In a patient with AIDS, endobronchial or pulmonary parenchymal Kaposi's sarcoma should be considered. Risk factors for bronchogenic carcinoma, particularly smoking and asbestos exposure, should be sought. Patients should be questioned about previous bleeding disorders, treatment with anticoagulants, or use of drugs that can be associated with thrombocytopenia.

• The physical examination may demonstrate a pleural friction rub (pulmonary embolism), localized or diffuse crackles (parenchymal bleeding or an underlying parenchymal process associated with bleeding), evidence of airflow obstruction (chronic bronchitis), or prominent rhonchi, with or without wheezing or crackles (bronchiectasis).

• Cardiac examination may demonstrate findings of pulmonary arterial hypertension, mitral stenosis, or heart failure. Skin examination may reveal Kaposi's sarcoma, arteriovenous malformations of Osler-Rendu-Weber disease, or lesions suggestive of systemic lupus erythematosus.

• Diagnostic evaluation of hemoptysis starts with a chest radiograph to look for a mass lesion, findings suggestive of bronchiectasis (

• . Additional initial screening evaluation often includes a complete blood count, a coagulation profile, and assessment for renal disease with a urinalysis and measurement of blood urea nitrogen and creatinine levels.

• Fiberoptic bronchoscopy is particularly useful for localizing the site of bleeding and for visualization of endobronchial lesions.

• , HRCT is now the diagnostic procedure of choice, having replaced bronchography.

– The rapidity of bleeding and its effect on gas exchange determine the urgency of management. When the bleeding is confined to either blood-streaking of sputum or production of small amounts of pure blood, gas exchange is usually preserved; establishing a diagnosis is the first priority.

– When hemoptysis is massive, maintaining adequate gas exchange, preventing blood from spilling into unaffected areas of lung, and avoiding asphyxiation are the highest priorities. Keeping the patient at rest and partially suppressing cough may help the bleeding to subside. If the origin of the blood is known and is limited to one lung, the bleeding lung should be placed in the dependent position, so that blood is not aspirated into