Respiration function test is a test which measures the air capacity and flow rate of the lungs. In diseases that restrict the movements of the chest or expansion of the lungs, lung volume decreases. In obstructive diseases of the airways , the air flow rate of the lungs decrease. Pathological changes can be detected by using respiration function tests, even before the subjective complaints of the patient begin.
Conditions where the respiration function tests are used:
- To search the reason for dyspnea, rustling respiration sound, persistant cough,
- To make the diagnosis certain which is suspected according to the physical exmination and chest x-ray,
- To examine the impact of the chest deformations to respiration, which are either inborn or acquired,
- The follow-up of the diagnosed COLD (Cronic Obstructive Lung Disease), asthma, heart failure and diseases that effect respiration muscles and evaluation of the therapies,
- The evaluation of labor loss due to diseases of the respiratory system,
- The screening of individuals or groups of people who are at risk for lung diseases because of their professions such as hard ankles, or who are exposed to dangerous gases, or smokers,
- The determination of respiratory complications due to general anesthesia or operation before the procedure and taking the necessary precautions for the patients at risk.
Bronchodilatation Test
The bronchodilatation test, which depends on showing the bronchodilatation that occurs due to short-term bronchodilators using spirometric methods, is performed for the ones who have airway obstruction. The response to bronchodilators are generally measured with the increase at forced expiratory volume in the first second (FEV1) and different medicine can cause such effects. The response rate of bronchodilator enables the differentiation between asthma and cronic bronchitis.
How the Respiration Function Tests are performed
The patient is in sitting position during the test. Before starting the procedure, the patient is adequately informed about it and then the nostrils of the patient are closed with a plastic latch and the patient is told to breath only through his/her mouth, thus preventing him/her from breathing through his/her nose. The patient breaths in and out through a disposable mouthpiece that is made up of millboard and so the test starts.
The test is composed of three stages : The patient should first breath normally and then should take a strong and deep breath and afterwards breath out quickly. This procedure is repeated approximately four times. At the last stage, the patient is told to breath in and out rapidly as if he/she were tired because of running. The test result is ready after all these stages are fulfilled and is evaluated by a specialist of chest diseases.