Classification
The diagnosis of COPD is divided into the four pillars. The pillars consist of:
- Physical examination
- Collection of laboratory parameters
- Pulmonary function test
- Imaging techniques
Physical examination
The diagnosis begins with a conversation (anamnesis) about the symptoms, followed by a detailed physical examination by the doctor. This clinical examination for chronic obstructive pulmonary disease (COPD) includes listening with a stethoscope, palpation and tapping. – In cases of pulmonary hyperinflation, tapping reveals a knocking sound (hypersonic), which is clearly different from a healthy sound (sonorous).
The shifting of the lung boundaries during breathing is reduced and when tapping, sounds may be heard. – When listening to the lungs with a stethoscope, the doctor can hear abnormal breathing sounds in the lungs during breathing. Particular attention is paid to rustling noises which are caused by the mucus produced by this disease.
Attention is also paid to dry noises. These can take the form of a humming or whistling. Such noises occur when the airways are narrowed.
The air accumulates in front of the constrictions. If such sounds can be heard, the disease is already more advanced. In addition, the sounds of breathing are much less audible than in a healthy person.
Laboratory diagnostics for COPD
Persons suffering from COPD show increased mucus production. This mucus is examined more closely in the laboratory. Analyses of the blood composition are also carried out.
Serum electrophoresis can be used if a rarer cause is suspected, e.g. an alpha-1-antitrypsin deficiency. Serum electrophoresis is a method of COPD, which separates blood proteins in an electric field to obtain a more precise composition of these proteins in the blood. In a blood gas analysis (BGA), the gas transport and gas content is finally assessed.
COPD – Pulmonary function test
If there is only a simple chronic bronchitis, the changes are usually only discreet. If the chronic obstructive pulmonary disease is already characterized by a narrowing, the pulmonary function test reveals changes such as a reduced one-second capacity FEV1. This parameter is determined by inhaling to the maximum and then exhaling as quickly as possible.
The volume of gas exhaled within one second is the one-second capacity and is recorded by a special measuring device. If the airways are narrowed, the volume is consequently reduced during this measurement. There is also increased resistance. This is the breathing resistance that must be overcome during breathing. Among other factors, it depends on the geometry of the airway, i.e. the diameter of the lumen.
Imaging techniques
There are various imaging techniques that can be used to diagnose COPD. – In order to get an overview and to exclude other diseases, an X-ray of the ribcage is taken, but only in about half of the affected persons a change can be detected. The doctor can detect the irreversible dilatation of the bronchioles and the alveoli associated with them.
Furthermore, it is possible to see a deep diaphragm with the help of the X-ray image. Furthermore, the X-ray image of a COPD is more translucent than that of a healthy lung. This is because there is less lung tissue.
Excluded are, for example, pneumonia, tuberculosis, inhaled foreign bodies or malignant tumours (tumour), all of which can also cause a chronic cough. – Computer tomography is also often used as a diagnostic procedure for COPD. The normal X-ray image of the lung is thus supplemented by this special X-ray procedure.
This procedure allows an even more detailed view of the lung. It is now displayed in two-dimensional slices. A computer puts these slices together in three dimensions, giving the doctor a three-dimensional impression of the lung.
The lung or its pathological changes are displayed without superimposition. Thus, no tissue is covered by tissue lying over it on the image. Therefore, tissue damage or pathological changes are much easier to see than with an X-ray image.
- The recording of the electrical heart activity in an ECG can provide indications of cardiac stress due to lung disease (cor pulmonale). – An MRI of the lungs can provide further indications of the extent of COPD. – Bronchoscopy, also known colloquially as lung endoscopy, allows the doctor to look inside the trachea and its large branches (bronchi).
The mucous membrane can thus be examined more closely. This facilitates the diagnosis of COPD. A pencil-thick tube (bronchoscope), which is flexible, is inserted into the airways through the mouth or nose.
At the end of the tube there is a video camera and a light source. The camera transmits all image signals to a monitor that the doctor looks at. In addition to observing and assessing the lung, the bronchoscope also makes it possible to take tissue samples.
