Bronchitis pathophysiology

Sethi S, Murphy TF. Acute exacerbations of chronic bronchitis new developments concerning microbiology and pathophysiology— impact on approaches to risk stratification and therapy. Infect Dis Clin North Am 2004 18 861-882. 

The sodium-channel inhibitor Amiloride is used for the treatment of chronic bronchitis, and the most frequently used anesthetic drug, lidocain, inhibits voltagegated sodium-channel a subunits, which mediate the pathophysiology of pain. 

The pathophysiological processes that develop in the upper and lower respiratory tract can greatly incapacitate a casualty or result in death within minutes of exposure. It is therefore imperative that adequate control of the casualty s airways be maintained. Medical personnel should look for hypoxia, hypercarbia, and pulmonary edema, all of which are signs of possible toxic inhalant exposure. Infectious bronchitis or pneumonitis (particularly in in-... 

Figure 1. Postulated pathophysiologic mechanisms in chronic bronchitis...

Bronchial asthma is characterized by an increased responsiveness of the trachea and bronchi to various stimuli and is manifested by a widespread narrowing of the airways that changes in severity either spontaneously or as a result of therapy (91). Chronic bronchitis is defined as a condition with chronic or recurrent bronchial hypersecretion, cough and expectoration during at least 3 months for at least 2 successive years (92). Chronic bronchitis is often associated with chronic airways obstruction with minimal reversibility it is then called chronic obstructive pulmonary disease (COPD). Chronic airways obstruction in COPD is believed to be caused by either emphysema or irreversible obstructive changes in the peripheral airways, or both. There is an overlap between asthma and COPD, and many patients may have features of both diseases (93). Asthma is considered an important risk factor for the development of COPD. Bronchial hyperresponsiveness is a hallmark of asthma, whereas its importance in COPD is more obscure. Airway inflammation is a key factor for the development of bronchial hyperresponsiveness (94). Table 4 shows the main pathophysiological features of airways obstruction in asthma, chronic bronchitis, and emphysema. 

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