Lung Function Test

Lung functions tests are mainly diagnostic tools that measure the various functions of the human lung. These tests help determine how your lungs are performing with regard to how well they process the air that we take in and if they are distributed well through the body. Lung volume or lung capacity is also measured through lung function tests. Other tests also help determine any physiological abnormalities of the lungs.

Lung function tests also help in the diagnosis of various respiratory disorders such as asthma and bronchitis. Conditions such as chest pain and shortness of breath may also be explored through spirometry. These tests are also used to determine the effects of medication on the lungs as also to examine the lungs of those who have been affected adversely by environmental factors or work hazards (coal mine workers or those who work with chemicals for example). In many cases, fitness for surgery or a procedure might be adjudged by a lung function test. Lung function tests help in checking for conditions like COPD (Chronic Obstructive Pulmonary Disease), sarcoidosis, asthma and lung tissue scarring.

Spirometry

Spirometry is the most commonly used test to measure and evaluate lung functions, while there are several other tests that pertain to more specific diagnostic needs. In the spirometry test, lung function is observed as the patient breathes into the spirometer. The patient's nostrils are usually clipped and a tight mouth piece is used. The patient will be monitored by a trained professional and asked to breathe at various paces in order to measure various test parameters and also the capacity of the lungs.

Peak Flow Meter: This hand-held device aids in tracking breathing and is especially helpful to those suffering wheezing and asthma.

Lung diffusion capacity: This lung function test helps in gauging how effectively oxygen is passed from the lungs to the bloodstream.

Lung volume measurement: This breathing test indicates the amount of air left in your lungs after breathing out.

Emphysema

A long term progressive disease of the lung, emphysema occurs when the alveolar walls of the lungs are destroyed. This reduces the total area within the lung where blood and air can come together thus limiting the possibility of oxygen and carbon dioxide transfer. Emphysema is grouped under COPD because this condition can destroy the lung tissue around the bronchioles (tiny airways) thus preventing them from holding on to their functional shape upon exhalation. This will cause permanent damage to the tiny air sacs.

Emphysema is common in people aged 50 and older. A few, with inherited emphysema may develop the condition in their early thirties or forties. Men are more susceptible to emphysema than women but recent times have seen an increase in female cases as the number of female smokers has gone up considerably. Smoking and Alpha-1 Antitrypsin Deficiency are the main causes for emphysema.

• Lungs do not contract to fullest extent because they lose their elasticity. This in turn stops the alveoli from deflating completely thereby making exhalation difficult.
  
  
• As complete exhalation has not happened, the next breath starts off with more air in the lungs.
  
  
• The entrapped old air takes up space. This prevents the alveoli from taking in enough fresh air as required so as to supply the required oxygen to the body.
  
  
• Shortness in breath while exerting a lot is reported commonly by patients with emphysema. People with advanced emphysema feel shortness in breath even while at rest.
  
  

Emphysema symptoms

• Shortness of breath while at rest
  
• Coughing
  
• Wheezing
  
• Difficulty to breath
  
• Skin turns bluish
  
• Excess mucus production
  

• Studying medical history of patient
  
• Physical/clinical examination
  
• Chest x-ray
  
• Medical imaging like CT scan of the chest
  
• Laboratory tests (blood)
  
• Lung function test
  

There is no permanent cure for emphysema. Treatment aims at slowing the development of the disease condition and reduce the symptoms. Medications are prescribed for relieving symptomatic conditions. Patients suffering this condition must stop smoking.