More Lung Disorders


Asthma is a common, chronic inflammation of the airways to the lungs (i.e. bronchi and bronchioles)

  • Inflammation leads to swelling and mucus production, resulting in reduced airflow and bronchospasm
  • During an acute asthma attack, constriction of the bronchi smooth muscle may cause significant airflow obstruction
  • Common symptoms of an asthma attack include shortness of breath, chest tightness, wheezing and coughing
  • Severe cases of asthma may be life threatening if left untreated

Asthma may be caused by a number of variable and recurring environmental triggers, including allergens, smoke, cold air, certain medications and arthropods (e.g. dust mites)

Physiology of an Asthma Attack



A pneumothorax is an abnormal collection of gas in the pleural space that causes an uncoupling of the lung from the chest wall

  • The pleural cavity is a thin, fluid-filled space between the lung and chest wall
  • Surface tension of the pleural fluid causes the lung to adhere closely to the chest wall and thus inflate upon chest expansion
  • If this cavity becomes filled with air (pneumothorax) or blood (haemothorax), the lung will collapse until the pressure is relieved
  • The build up of fluid or gas will also compress other local organs (including the heart), resulting in life threatening complications

A pneumothorax is typically treated by inserting a syringe into the pleural cavity and draining the excess liquid or gas

Physiology of a Pneumothorax