Chronic Bronchitis | Causes of Bronchitis 

Bronchitis is considered “chronic” if symptoms continue for three months or longer. Bronchitis caused by allergies can also be classified as chronic bronchitis. There are many causes of chronic bronchitis, but the main cause is cigarette smoke.

Many other inhaled irritants (for example, smog, industrial pollutants, toxic gases in the environment or workplace and solvents) can also result in chronic bronchitis. Viral and bacterial infections that result in acute bronchitis may lead to chronic bronchitis if people have repeated attack with infectious agents. Also, underlying disease processes (for example, asthma, cystic fibrosis, immunodeficiency, congestive heart failure, familial genetic predisposition to bronchitis, and congenital or acquired dilation of the bronchioles) may cause chronic bronchitis to develop, but these are infrequent causes compared to cigarette smoking.

Risk Factors Of Chronic Bronchitis

The major risk factor for individuals to develop chronic bronchitis are; Tobacco smoking and second – hand tobacco smoke exposure, repeated exposure to pollutants (especially airborne materials such as ammonia, sulphur dioxide, chlorine, bromine, hydrogen sulphide), dust, repeated attack of acute bronchitis or pneumonia, and gastric reflux (by inhalation of gastric contents).

Pathophysiology

The disease is caused by an interaction between noxious inhaled agents and host factors, such as genetic predisposition or  respiratory infections which cause injury or irritation to the respiratory epithelium of the walls and lumen of the bronchi and bronchioles. Chronic inflammation, edema, temporary bronchospasm, and increased production of mucus by goblet cells are the result. As a consequence, airflow into and out of the lungs is reduced, sometimes to a dramatic degree. Most cases of chronic bronchitis are caused by smoking cigarettes or other tobacco products, although other examples of noxious agents include fumes from cleaning products and solvents, dust from occupational exposure, and air pollution. Ammonia, sulphur dioxide, chlorine, bromine, and hydrogen sulphide are especially harmful pollutants which are linked to respiratory diseases. Chronic bronchitis must be distinguished from common allergies which also cause mucus hypersecretion and coughing fits. When chronic bronchitis progresses to include the pathologic changes of emphysema, it is often referred to as COPD.

Symptoms

•  Bluish skin due to lack of oxygen (cyanosis).
• Breathing difficulty including wheezing and shortness of breath.
•  Cough and sputum production are the most common symptoms; they usually last for at least 3 months and occur daily. The intensity of coughing and the amount and frequency of sputum production vary from patient to patient. Sputum may be clear, yellowish, greenish, or occasionally, blood-tinged.
•  Fatigue.
• Fever may indicate a secondary viral or bacterial lung infection.
• Muscles around the ribs sink in as the child tries to breathe in (called intercostal retractions).
• Infant’s nostrils get wide when breathing
• Rapid breathing (tachypnea).In addition, symptoms of sore throat, muscle aches, nasal congestion, and headaches can accompany the major symptoms. Severe coughing may cause chest pain.

Diagnosis

Medical history: It include past and current smoking habits and live with someone who smokes, any history of on the job exposure to airborne irritants and any family history of respiratory diseases, such as cystic fibrosis or emphysema.

Physical exam: Physical exam include wheezes (high-pitched sounds that occur
when air is pushed out through constricted airways), and rales (small rattling sounds
that result when air moves through airways filled with fluid). The vibration from the
chest percussion helps to determine the size and condition of the lungs.

•  Complete blood cell count (CBC).
• Arterial blood gases (ABG) test.
•  Chest X-ray.
• Spirometry.
• ECG.

Treatment

The goal of therapy for chronic bronchitis is to relieve symptoms, prevent complications and slow the progression of the disease. Quitting smoking is the most important and most successful treatment for chronic bronchitis, since continuing to use tobacco will only further damage the lungs.

Medications used for treatment bronchitis are:

Bronchodilator: Salmeterol, Albuterol, Metaproterenol and Formoterol

Anticholinergic: Ipratropium bromide and Tiotropium

Steroids: Presnisone, Dexamethasone

PDE4 inhibitors: Roflumilast

Antibiotics: Macrolides, Azithromycin sulfonamides, Tetracyclines, Trimetho-prim
and Fluoroquinolones

Vaccines: Patients with chronic bronchitis should receive a flu shot annually and pneumonia shot every five to seven years to prevent infections.

Oxygen Therapy: As a patient’s disease progresses, they may find it increasingly difficult to breathe on their own and may require supplemental oxygen.

Surgery: Lung volume reduction surgery, during which small wedges of damaged lung tissue are removed, may be recommended for some patients with
chronic bronchitis.

Pulmonary Rehabilitation: An important part of chronic bronchitis
treatment is pulmonary rehabilitation, which includes education, nutrition counselling,
learning special breathing techniques, help with quitting smoking and starting an exercise regimen. Because people with chronic bronchitis are often physically uncomfortable, they may avoid any kind of physical activity. However, regular physical
activity can actually improve a patient’s health and well-being.

Cough suppressants: Cough suppressants such as dextromethorphan may be helpful in reducing cough symptoms.

Prevention

The majority of instances of  can be prevented by quit smoking
and avoiding second-hand smoke. Flu and pneumococcal vaccines can help to prevent repeated infections that may lead to the disease. Certain industries (for example,
chemical, textile, thermal etc.) and farm workers are often associated with air-borne
chemicals and dust; avoiding air-borne chemicals and dust with appropriate masks
may prevent or reduce the individual’s chance of developing chronic bronchitis.
Good control of asthma may prevent  from developing. The genetic predisposition to  is not currently preventable.

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Acute Bronchitis | What Is Bronchitis | Symptoms Diagnosis Treatment