Prognosis & Complications

• Prognosis depends on:
o Severity of lung disease
o Smoking status of patient
• FEV1 > 50% predicted: survival only slightly less than patients without COPD
• FEV1 < 0.75 L (very severe obstruction, < 30% predicted): 1-year mortality rate of 30% and a 10-year mortality rate of 95%
• At any level of lung impairment, prognosis improves when the patient quits smoking.

Cor Pulmonale
- an increase in bulk of the right ventricle of the heart, generally caused by chronic diseases or malfunction of the lungs (e.g. COPD). This condition can lead to heart failure.

Acute Exacerbations
Acute exacerbations of COPD are characterized by an abrupt increase of symptoms:
• Cough and sputum production increases
• Wheezing is often increased or noted for the first time
• Dyspnea is increased or apparent for the first time.

During an acute exacerbation, there is increased airway narrowing due to:
• Bronchospasm
• Edema
• Excessive mucus production.

If narrowed airways cause an extreme increase in the work of breathing that cannot be maintained, the patient will die, unless there is intervention (e.g. mechanical ventilation).

End-stage lung disease
- The final stages of lung disease, when the lung can no longer keep the blood supplied with oxygen.

When respiratory failure occurs in a patient who has end-stage lung disease, there is a slow decline in lung function and rising levels of carbon dioxide in the blood. The increasing carbon dioxide creates a narcotic effect in the patient, who slowly loses consciousness and stops breathing.

Pneumonia
Streptococcus pneumoniae is the most common cause of bacterial pneumonia in patients with COPD. This can lead to respiratory failure.

Pneumothorax
Patients with COPD are at increased risk for spontaneous penumothorax because of weakened lung structure. This can lead to severe respiratory distress and is treated by inserting a tube into the pleural cavity to allow the air to escape out and re-expanding the lung.

Polycythemia
The body attempts to adjust to decreased amounts of blood oxygen by increasing the production of erythrocytes. While this may be helpful in the short term, overproduction eventually clogs small blood vessels.

http://www.pulmonologychannel.com/copd/complications.shtml