Chronic Obstructive Pulmonary Disease (COPD) is a chronic progressive disease that is mainly caused by smoking although environmental factors, genetic susceptibility and exposure to harmful substances at work can cause or contribute to the development of the disease.
COPD is a term that refers to the co-existance of asthma, chronic bronchitis and emphysema in an individual. The distribution of disease varies between individuals, some people may have a greater degree of chronic bronchitis than emphysema and vice versa.
Chronic Asthma/Chronic Bronchitis – Inhalation of harmful substances causes irritation of the bronchial wall and the release of neutrophils and other inflammatory mediators. This causes airway inflammation and narrowing, and an increase in mucus production. The airway narrow is usually irreversible.
Emphysema – Neutrophils also trigger the release of enzymes (proteases) that damage the elastic properties of the lung and alveoli. Alveoli merge into large inelastic sacs that close and collapse during expiration. This results in air trapping and lung hyperinflation which increase the work of breathing.
How does the endobronchial valve work?
The valve stops air inflow to the treated area of the lung which results in collapse or closure of the diseased area. It allows air and mucus to escape during expiration. This prevents air trapping and hyperinflation and reduces the work of breathing.
Who should be referred for an endobronchial valve?
Research is ongoing. A multidisciplinary team experienced in the management of emphysema should be involved in the selection process. NICE (2013) recommend that the team include a chest physician, a chest radiologist and a thoracic surgeon. Distribution of disease and assessment of collateral ventilation appear to be significant.
How is the procedure carried out?
The insertion of endobronchial valve is done using a bronchoscope with the patient sedated or anaesthetised.