The organs in the body need oxygen in order to function. This reaches the lungs via the airways. There it enters the bloodstream in a process known as gas exchange. The heart pumps the blood with the oxygen through the entire body so that the organs are supplied with oxygen.
If they do not receive oxygen, they cannot perform their function and even die after a prolonged lack of oxygen. This is why an undersupply of oxygen is immediately reported to the brain, which triggers the feeling of breathlessness.
Shortness of breath, also known as dyspnoea, is a subjective feeling. The person affected thinks and feels that they are no longer getting enough air. In response, the body increases the breathing rate.
Normally, a person takes around 15 to 20 deep breaths per minute. By increasing the frequency, these breaths become faster and therefore shallower, which leads to shortness of breath.
By increasing the breathing rate, the body tries to increase the oxygen content in the blood and thus compensate for the deficiency.
Oxygen enters the lungs via the airways and from there into the bloodstream. Oxygen deficiency leads to shortness of breath © Henrie | AdobeStock
Shortness of breath can be caused by a variety of diseases. In most cases, shortness of breath is caused by a lung disease. Shortness of breath can be a symptom of the following lung diseases:
The heart is responsible for the distribution of oxygen in the blood. Heart disease can therefore also cause breathlessness. Heart diseases that can be associated with breathlessness include
Various laryngeal and tracheal diseases can also cause shortness of breath. These include
There are also other diseases and situations that cause shortness of breath. These include psychological causes such as a panic attack. The panic attack can lead to hyperventilation. This means that the person affected breathes faster and faster and therefore more shallowly, causing the CO₂ concentration in the blood to drop. The body receives too little oxygen and becomes short of breath.
But also
can lead to shortness of breath.
In addition to internal conditions, certain environmental conditions also sometimes lead to shortness of breath. For example, a lack of oxygen during a mountain climb at high altitude can lead to breathlessness.
Shortness of breath can also be caused by foreign substances in the airways or smoke inhalation.
As dyspnoea can be caused by various illnesses, a medical examination is necessary. The doctor will first take the patient's medical history. He will ask about important lifestyle habits and circumstances such as
- smoking habits,
- previous illnesses or
- the intake of medication.
The circumstances of the breathlessness are also examined in more detail. This includes, for example, the frequency of occurrence as well as the duration, location and time of the breathlessness.
Various examinations are then useful. The doctor will listen to both the heart and lungs with a stethoscope to check for any unusual symptoms.
The physical examination includes a blood test and an electrocardiogram (ECG). An ECG shows the electrical excitation of the heart. This enables the doctor to determine whether acute heart disease is present.
An X-ray examination of the chest and a lung function test are also often carried out. These provide information as to whether there is any dysfunction of the lungs or airways.
The further procedure depends on what illness the doctor suspects. Sometimes an allergy test or a biopsy are informative. In the latter case, a tissue sample is taken from the patient and then examined under a microscope.
An endoscopy of the bronchi or larynx can also make the diagnosis easier. In some cases, a computer tomography (CT) scan is necessary to find the exact cause of the breathlessness.
The successful treatment of breathlessness depends on the cause.
In the case of acute bronchitis, short-term treatment with antibiotics may be advisable until the illness has healed. In the case of other diseases such as COPD or asthma, on the other hand, the person affected must be treated with medication for the rest of their life.
In some cases, surgery or chemotherapy is also advisable, for example in the case of a tracheal tumor.