What is low oxygen saturation?
Oxygen saturation refers to the proportion of hemoglobin that has bound oxygen. Hemoglobin is a protein complex that binds oxygen in the red blood cells. Colloquially, hemoglobin is also known as the pigment of the red blood cells.
It is loaded in the lungs and transports the oxygen to the organs. Oxygen saturation is also an important parameter for assessing respiratory function. A high oxygen saturation is important to supply all organs with the valuable oxygen.
It can be measured with a pulse oximeter, which is often attached to the finger. A value between 96% and 99% is normal. Below 96% is called a reduced oxygen saturation, below 90% it needs treatment.
What are the causes of reduced oxygen saturation?
There are a variety of causes for reduced oxygen saturation. The most common causes are lung diseases. These include diseases like: But also diseases of other organs can lead to a decreased oxygen saturation, such as Other causes can be carbon monoxide poisoning in fires.
But there does not have to be a disease. Even with anesthesia, a lowered oxygen saturation can occur in the short term. It is used by the anaesthetist to assess the anaesthesia.
- COPD
- Bronchial asthma
- Lung tumors
- Pulmonary fibrosis
- Pneumonia.
- Heart Failure
- Circulatory disorders
- Kidney diseases with disorders of the acid-base balance
Chronic Obstructive Pulmonary Disease (COPD) is a very common lung disease affecting mainly elderly people and smokers. It causes a chronic narrowing of the airways. The narrowing prevents the lung from developing when inhaled and leads to a loss of the oxygen exchange surface.
As a result, not every hemoglobin molecule can be loaded with oxygen. As the disease progresses, patients have increasingly low oxygen saturation. Initially, this can be compensated by the body, but in the long term, the patients need additional oxygen from bottles.
Pneumonia, also known as pneumonia, is an inflammation of the lung tissue and alveoli as a result of a bacterial infection. In addition to symptoms such as fever, cough and a feeling of illness, there is also a reduced oxygen saturation. Patients often have difficulty breathing due to the inflammation.
In addition, there is often a formation of mucus that covers the oxygen exchange surface, so that haemoglobin can no longer be loaded with oxygen as well. During anaesthesia, fluctuations in oxygen saturation often occur. It is used by the anaesthetist to assess the anaesthesia.
Under anaesthesia, the human lung is artificially ventilated by a ventilator. There are various options for anesthesia and ventilation. If the ventilation is not sufficient or if there are problems, the anaesthetist can see this from the low oxygen saturation.
Then the anaesthetist can increase the oxygen supply. Usually, these short-term fluctuations do not affect the patient. In bronchial asthma, a chronic inflammation leads to a narrowing of the airways.
The symptoms usually manifest themselves with shortness of breath and nocturnal coughing. Often an allergic genesis is present. Similar to asthma, the constriction leads to a reduced oxygen exchange surface. In addition, there is often a massive formation of mucus, which also reduces the area. As a result, oxygen uptake is disturbed and oxygen saturation is lowered.
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