Classification of COPD in stadiums
COPD is divided into different stages, depending on the severity of the disease. One possible classification divides the disease into four different stages based on values obtained from the lung function test. Stage 1 is the mildest severity, stage 4 is the most severe form of the disease.
Alternatively, the classification is based on the severity of the respiratory distress. This classification divides COPD into severity grades 0 to 4. In addition, there is also the stage classification which is called GOLD A to D. This classification is based on several parameters.
These include the lung function test and the clinical symptoms. Stage 1 of COPD is characterized by a one-second capacity of less than 80% of the target value in lung function. For the one-second capacity test, the patient takes a deep breath and must then exhale everything as quickly as possible.
The proportion of air that can be exhaled within one second is measured and is decisive for determining lung function. Stage 1 is comparable to the GOLD A classification. In this case, respiratory distress is only present during heavy physical exertion, when walking fast and when going uphill.
The clinical symptoms (coughing, sputum, sleep quality) are hardly or only slightly restrictive in everyday life. In stage 2 there is a one-second capacity of 50 to 79%. This means that in the one-second capacity test, the affected persons could exhale significantly less air compared to other healthy people.
During exertion, there is increased difficulty in breathing, which is why those affected go for walks more slowly than their peers. In addition, normal walking requires breaks. In the GOLD classification, stage 2 corresponds to the GOLD B.
The difference to the first stage is primarily a significantly increased conspicuousness of coughing, sleep and quality of life, which is associated with a restriction in everyday life. In both stages exacerbations (derailments) of the disease occur at most once a year. In stage 3, lung function testing reveals a one-second capacity of 30 to 49%.
When walking, affected persons have to take more breaks. By definition, these breaks take place after about 100 metres of walking and last a few minutes. The stage is comparable to GOLD C. In these persons, two or more exacerbations a year occur, the clinical symptoms are also noticeable, so that they limit the daily routine, but many everyday tasks can still be performed normally.
Stage 4 is the most severe stage of COPD. The one-second capacity in lung function in stage 4 is only 30% of the target value. In addition, people with a one-second capacity of less than 50% and an additional lack of oxygen requiring treatment (oxygen pressure < 60 mmHg) or increased CO2 content in the blood (CO2 pressure > 50 mm Hg) are classified in this stage.
In most cases, affected persons can hardly leave the house due to severe shortage of air, they are often no longer able to supply themselves independently. The GOLD D stage is comparable. Here too, more than 2 exacerbations per year are to be expected, the clinical symptoms are very restrictive in everyday life.
End-stage COPD is determined by a strong restriction in everyday life. Those affected often suffer from such severe shortness of breath that they are hardly able to leave the house. In most cases they are no longer able to look after themselves.
In addition, there is an increased susceptibility to infections, especially in the final stage. Thus a simple cold can quickly derail and lead to a life-threatening deterioration. The narrowing of the airways leads to a lot of air remaining in the lungs that cannot be breathed out.
This so-called air trapping leads to an over-inflation of the chest. In addition, the air remaining in the lungs is not very rich in oxygen. This not only causes a lack of oxygen in the entire body, but also constricts the blood vessels in the affected lung sections.
In the final stage of the disease, this vasoconstriction can lead to increased pressure in the lungs. The heart has to permanently pump against this pressure. If the heart muscle cells are no longer able to compensate for this increased demand, cardiac insufficiency also occurs. This particularly affects the right half of the heart.
