This page has moved. Click here to view.


Chronic Obstructive Pulmonary Disease

Pathogenesis

Emphysema and chronic bronchitis are the main disease states in chronic obstructive pulmonary disease, although there is usually significant overlap between the two conditions. Smoking is the single overwhelming risk factor for the development of COPD.

Emphysema is characterized by permanent enlargement of alveolar air spaces with destruction of the alveolar walls chronic obstructive pulmonary disease, bronchitis, chronic bronchitis, emphysema, emphasema, empasemia, emfasemia, emphysemea

Chronic Bronchitis is defined as chronic sputum production and variable degrees of airway obstruction for more than 3 months in each of 3 successive years.

Diagnosis of Chronic Obstructive Pulmonary Disease

Symptoms are often insidious and may be manifest early by exercise intolerance only; later symptoms include wheezing, dyspnea, chronic cough, sputum production, recurrent pneumonias, bronchitis.

Signs: Wheezing, decreased air movement in the chest, hyperinflation, prolonged expiratory time, barrel chest, and supraclavicular retractions.

Pulmonary Function Testing:

Significant airway obstruction is present when the forced expiratory volume in 1 sec (FEV1) is less than 80% of predicted, and the FEV1/Forced Vital Capacity ratio is less than 70% of predicted.

Hyperinflated lungs are bronchitis, chronic bronchitis indicated by increased total lung capacity and residual volume, and by loss of alveolar surface area and decreased diffusing capacity.

Management Of Chronic Obstructive Pulmonary Disease

Smoking Cessation bronchitis is effective in halting the progression of chronic obstructive pulmonary disease.

Beta Agonists:

Beta2-adrenergic Agonist should be used for occasional "as needed" use for symptom relief.

Side Effects: Tremor, nervousness, tachycardia, hypokalemia in higher doses.

Dosages:

  1. Albuterol (Ventolin), aerosol MDI 2-3 puffs tid-qid prn, or powder 200 mcg/capsule inhaled qid prn.
  2. Pirbuterol (Maxair) MDI 1-2 puffs tid-qid prn.
  3. Bitolterol (Tornalate) MDI 2-3 puffs tid-qid prn.
  4. Fenoterol (Berotec) MDI 3 puffs initially, then 2 puffs bid-qid prn.
  5. Salmeterol (Serevent) 2 puffs bid; long-acting agent; useful for nocturnal COPD; not effective for emphysema, emphasema.
Technique for Usage of Metered Dose Inhalers:
  1. Invert and shake inhaler briskly with the opening downward.
  2. Hold inhaler 2 fingerbreadths in front of open mouth.
  3. Exhale normally to functional residual capacity.
  4. Inhale slowly and deeply to total lung capacity.
  5. Hold breath for 10 seconds.
  6. Exhale slowly. Wait 3-5 minutes and repeat.
Anticholinergic Agent:
  1. Ipratropium bromide (Atrovent): 2-6 puffs qid or nebulized qid. Does not have systemic, atropine-like side effects because it is not absorbed from the respiratory mucosa
  2. Should be used regularly with a beta agonist for most patients with COPD.
Corticosteroids:
  1. Effect in COPD is less pronounced than in asthma. Most beneficial during exacerbations; only a small percentage (10-20%) of outpatients with COPD respond to corticosteroids.
  2. Aerosolized corticosteroids provide the benefits of oral corticosteroids with fewer side effects. Oropharyngeal candidiasis can be prevented by using proper technique and by rinsing throat with water after use.
Treatment of Complications of COPD
  1. Infection:
    1. Infection frequently causes bronchitis exacerbations, and is associated with increased or purulent sputum, increased cough, chest congestion and discomfort, and increased dyspnea and wheezing. Chills and fever suggest pneumonia. Acute bacterial episodes tend to be seasonal, appearing more frequently in winter.
    2. Gram's Stain:
      1. Gram stain is a useful guide in the selection of an empiric antibiotic.
      2. First confirm that the specimen is sputum and not saliva; the presence of more than 25 neutrophils and fewer than 10 epithelial cells per low-power field is indicative of sputum.
      3. The presence of bacteria on high-power examination of such a specimen is presumptive evidence of infection. Although patients with COPD can be colonized by influenzae and pneumoniae, these organisms should not be present in sufficient numbers to be seen on a Gram stain.
    3. Sputum culture and sensitivity testing are generally not necessary but may be required if the patient is very ill or if the infection is hospital-acquired.
    4. A chest film is helpful in ruling out pneumonia or other disorders.
    5. The primary pathogens for COPD exacerbations include H influenzae, parainfluenzae, S pneumoniae, and Moraxella catarrhalis. Other less common pathogens are staphylococci, Neisseria, Klebsiella, and Pseudomonas.
    6. Treatment of Exacerbations of COPD:
      1. The selected antimicrobial agent should have good in vitro activity against the primary causative pathogens: Haemophilus species, S pneumoniae, and M catarrhalis, and not be hydrolyzed by beta-lactamase.
      2. Treat 7-10 days.