bronchitis
(brong-kīt'ĭs 
)
[ broncho- + -itis ]
Inflammation of the mucous membranes of the bronchial airways, caused by irritation or infection, or both, by pathogen. Bronchitis can be acute or chronic.
Causes: Bronchitis is caused by infectious agents such as viruses (particularly rhinoviruses, influenza A and B, parainfluenza, adenoviruses, and respiratory syncytial virus) or, less often, by species of Mycoplasma, Chlamydia, streptococcus, Haemophilus, Branhamella, or staphylococcus. Infection is often indistinguishable from the common cold and is usually treated as such unless pneumonia is also present. Acute bronchial irritation (noninfectious bronchitis) may also be caused by exposure to various physical and chemical agents such as dust, fumes, or pollens. Allergies and preexisting conditions such as asthma or chronic obstructive lung disease may be important cofactors.
Patient Care: A history is obtained documenting tobacco use, including type, duration, and frequency. Calculation of pack-year history gives useful information. The health care provider assesses for other known respiratory irritants and allergens, exertional or worsening dyspnea, and productive cough. The patient is evaluated for changes in baseline respiratory function such as the use of accessory muscles in breathing, cyanosis, neck vein distention, pedal edema, prolonged expiratory time, tachypnea, and wheezes or crackles. The color (gray, white, or yellow) and characteristics of sputum are often documented but may have little diagnostic significance. Tests such as arterial blood gas analysis, chest x-rays, oximetry, peak flow measurements, pulmonary function testing, and sputum Gram stain are occasionally employed. They are explained to the patient if they have been ordered. Prescribed antihistamines, bronchodilators, corticosteroids, decongestants, expectorants, and other medications are administered and the response is documented. Antibiotics are rarely indicated. Daily activities are interspersed with rest periods to conserve energy and to prevent fatigue. Patients with comorbid conditions should be hospitalized, in which case all general patient care concerns apply. Patients needing help to quit smoking are given counseling and support and referred to smoking cessation programs and for adjunctive drug therapy when prescribed.
acute b.1An infection of the bronchi that may be indistinguishable from the common cold, often associated with repetitive coughing or sputum production. It is usually caused by viruses (particularly rhinoviruses, influenza A or B, parainfluenza, adenoviruses, or respiratory syncytial virus) or less often by Mycoplasma pneumoniae, Chlamydia, streptococci, Haemophilus spp, Moraxella lacunata, Bordetella pertussis, or staphylococci.2Noninfectious inflammation of the bronchi caused by exposure to irritants such as dust, fumes, or pollens.
Patients are treated with bedrest, increased fluid intake, and antipyretics and analgesics for comfort. Antibiotics are rarely indicated (even if purulent sputum is present), unless bacterial infection is determined by culture, the symptoms continue for more than 10 days, or there is an underlying disease such as congestive heart failure, chronic obstructive lung disease, or an immunodeficiency. Some prolonged cases of acute bronchitis eventually prove to be caused by pertussis, which responds to erythromycin-based drugs. A chest x-ray examination to check for pneumonia is indicated when clinically suspected (the presence of severe respiratory symptoms, fever, tachycardia, hypoxia, or abnormal lung sounds).
asthmatic b.Bronchitis compounded by wheezing, caused by spasm of hyperreactive airways.
chronic b.Bronchitis marked by increased mucus secretion by the tracheobronchial tree. A productive cough must be present for at least 3 months in two consecutive years for the clinical diagnosis of chronic bronchitis to be made; also, other bronchopulmonary diseases (such as bronchiectasis, tuberculosis, tumor) must be excluded.
SEE: chronic obstructive pulmonary disease.
According to the 2011 National Health Interview Survey, chronic bronchitis is found in approx. 44 of every 1000 adults in the U.S.
Chronic irritation by inhaled irritants (esp. cigarette smoking) and repeated infections are the primary risk factors. Chronic bronchitis is four to ten times more common in heavy smokers; cigarette smoke interferes with the movement of cilia and inhibits the activity of white blood cells in the bronchi and alveoli. The predominant pathological changes are hypertrophy and hyperplasia of the mucus-secreting gland s of the large and small airways. Some patients also have hyperreactive airways with widespread inflammation, narrowing and distortion. The changes in the respiratory epithelium may increase the risk of lung cancer.
Although the disease begins earlier, signs and symptoms may not appear until patients are 40 to 50 years old. A chronic cough producing copious amounts of sputum occurs early, and patients have frequent respiratory problems, often as a result of acute bronchopulmonary infections. Dyspnea is generally moderate and occurs relatively late in the disease process. Over time, right-sided heart failure (cor pulmonale) develops, marked by dependent edema, distended neck veins, pulmonary hypertension, and an enlarged right ventricle.
Diagnostic studies may include chest x-ray, pulmonary function or peak flow testing, arterial blood gas studies, and an electrocardiogram.
Bronchodilators, inhaled steroids, and other drugs are used to prevent bronchospasm, improve airflow, and aid in the removal of secretions. Increased fluid intake (about 3 L/day), ultrasonic or mechanical nebulizer treatments, and chest physiotherapy may be needed to help thin, loosen, and remove secretions. Acute respiratory infections are treated with empirical antibiotics such as azithromycin or trimethoprim/sulfamethoxazole, among others. Patients with underlying chronic bronchitis should receive pneumococcal and influenza vaccines. Other treatments are symptom based. Cessation of smoking is an important part of the overall treatment. Oxygen therapy is frequently needed.
The initial history and assessment cover the use of tobacco, the presence of other known respiratory irritants and allergens, the degree of dyspnea, the use of accessory muscles for breathing, the presence of wheezes or rhonchi, the color and characteristics of sputum, nutritional status, and the effect of the disease on desired activity. Patients who smoke are referred to a smoking cessation program. The patient's lungs are auscultated before and after aerosol therapy to assess the effectiveness of bronchodilators.
The patient and the patient's family need extensive education and ongoing psychosocial support to cope with this chronic disease. Simple pathophysiology of the disease process is taught and used as a basis for explanations about diagnostic tests (such as pulmonary function tests) and all interventions to increase patient cooperation in the complex care regimen. Written materials usually augment verbal instruction. Patients and families are taught how to ensure and document adequate fluid intake (about 3 L/day unless otherwise restricted) to loosen secretions; to schedule small, frequent, high-protein meals to combat anorexia and weight loss; to use pursed-lip breathing and controlled cough to increase airflow and prevent fatigue from coughing spasms; to provide oral care frequently to minimize anorexia and the risk of infection; and to maintain muscle strength by continuing to exercise, but with a plan to pace activities to avoid fatigue. They also are taught to watch for and report signs of possible heart failure (such as dependent edema, or weight gain of more than 1 kg/day) or acute respiratory infection, e.g., increased dyspnea and changes in sputum characteristics such as color or amount. As the disease progresses, the family is assisted to make decisions about how routines may be modified to best meet individual needs.
The respiratory therapist delivers bronchodilators and other inhaled medications, e.g., steroids, as indicated by the presence of wheezing or evidence of retained airway secretions. Chest physical therapy may prove useful when the patient cannot easily cough up the secretions. Oxygen therapy is administered based on evidence of hypoxemia, inadequate perfusion of vital organs, or cor pulmonale.
chronic desquamating eosinophilic b.Asthma.
eosinophilic b.Bronchitis marked by chronic cough, eosinophils in the sputum, and improvement in symptoms after the administration of corticosteroids. It is similar to asthma, but there is no wheezing or airway reactivity, and the airways are not infiltrated by mast cells.
plastic b.Bronchitis marked by violent cough and paroxysms of dyspnea in which casts of the bronchial tubes are expectorated.
putrid b.Chronic bronchitis with foul-smelling sputum.
vegetal b.Bronchitis resulting from lodging of foods of vegetable origin in the bronchus.