• NBRC matrix: references for all three exams.

  • Etiology - Cigarette smoking is the main cause of chronic bronchitis. The longer a person smokes, the more likely and more severe the onset of bronchitis will develop. Exposure to second hand smoke, air pollution, and chemical fumes are ways someone could develop chronic bronchitis. Viral and bacteria infections that result in acute bronchitis may lead to chronic bronchitis if the person has repeated bouts with the infectious agent. Also, underlying disease processes such as: asthma, cystic fibrosis, immunodeficiency, congestive heart failure, familial genetic predisposition to bronchitis, and bronchiectasis may cause chronic bronchitis to develop.

  • Pathophysiology - The initiating event in developing chronic bronchitis appears to be chronic irritation due to inhalation of certain substances such as cigarette smoking. The earliest clinical feature of bronchitis is increased secretion of mucus by submucousal glands of the trachea and bronchi. Damage caused by irritation of the airways leads to inflammation and infiltration of the lung tissue by neutrophils. The neutrophils release substances that promote mucousal hypersecretion. As bronchitis persists to become chronic bronchitis, a substantial increase in the number of goblet cells in the small airways is seen. This leads to further increased mucous production that contributes to the obstruction of the airways. The role of infection in the pathogensis of chronic bronchitis appears to be secondary. However, although infection is not responsible for initiating bronchitis, it may have an important role in maintaining it. Acute exacerbations of the long-standing bronchitis may result from infections.

  • Clinical manifestations (symptoms)

    • Chronic cough that produces mucus and sputum, shortness of breath (dyspnea) that gets worse with mild activity, wheezing, and frequent respiratory infections. Occasionally may experience fever, fatigue, head ache, and chest pain.

    • Complications include: arrhythmia, right heart failure (cor pulmonale), pneumonia, pneumothorax, and development of emphysema.

  • Methods of diagnosis: A person who experiences a chronic cough and excessive mucus production for 3 months or more in at least 2 consecutive years that is not caused by any other disease or condition.

    • Initial presentation: It is very common for the patient to have a chronic productive cough producing copious amounts of sputum. Patient with chronic bronchitis typically appear stocky or overweight rather than thin. The patient may have a diminished respiratory drive and hypoventilating. The patient may appear to have central cyanosis.

    • Other test used to diagnose chronic bronchitis include:

      • Pulmonary Function Test (PFT) is used to measure FEV1/FVC ratio. A FEV1/FVC ratio of less than 70% that is not reversible after bronchodilator therapy indicates the presence of chronic obstructive pulmonary disease or COPD.

      • Chest X-Ray is used to reveal hyperinflation and increased bronchovascular markings.

      • Chest CT scan

      • ECG: Can be used to identify CHF (Cor pulmonale and Pulmonary Edema).

      • Pulse Oximetry

      • Arterial Blood Gas: Hypoxemia, Compensated Respiratory Acidosis.

      • Complete Blood Count: Increase in HbG, polycythemia.

      • Sputum Culture

  • Management and treatment - The goal for treatment of chronic bronchitis is to reduce inflammation and congestion, improve work of breathing, and decrease hypoxemia.

    • Quitting smoking is the best way to improve symptoms of chronic bronchitis.

    • Avoid second-hand exposure of smoking, chemical fumes, smog, etc.

    • Drug Therapy: Bronchodilator and corticosteriods can be used to relax the smooth muscle in the bronchi and to reduce inflammation.

    • Antibiotics are used to treat chronic bronchitis exacerbations caused by bacterial infections.

    • Oxygen therapy can be used in a home care setting.

    • Bronchial hygiene therapy maybe performed to mobilize retained secretions.

  • Prognosis- Patients with mild to moderate cases of chronic bronchitis may often be controlled with routine medications and pulmonary rehabilitation programs. Advanced chronic bronchitis is more difficult to treat and may seldom require the use of oxygen or consideration of lung transplantation. Early recognition, treatment, and smoking cessation can significantly improve the outcome of people suffering from chronic bronchitis. COPD is the 3rd or 4th leading cause of death in the U.S. and a major economic burdern on patients. It decreases in the patients quality of life.

References Used

1. Wilkins, R. L., Stoller, J. K., & Kacmarek, R. M. (2009). Egan's Fundamentals of Respiratory Care Ninth Edition. St. Louis, MI: Mosby, Inc.

2. Des Jardins, T. & Burton, G. G. (2011). Clinical Manifestations and Assessment of Respiratory Disease Sixth Edition. Maryland Heights, MI: Mosby, Inc.

3. Oakes, D. F. (2008). Oakes' Clinical Practitioner's Pocket Guide to Respiratory Care 7th Edition. Orono, MN: Health Educator Publications, Inc.

4. PubMed Health. (2011). Bronchitis. Retrieved July 24, 2011, from http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002078/.

5. The Ohio State University Medical Center. (2011). Chronic Bronchitis. Retrieved July 24, 2011, from http://medicalcenter.osu.edu/patientcare/healthcare_services/lung_diseases/lung/bronchitis/pages/index.aspx

Chest X-Ray of Chronic Bronchitis