Blood oxygen level is the amount of oxygen circulating in the blood. Most oxygen is carried by red blood cells, which collect oxygen in the lungs and transport it to all parts of the body. The body closely monitors the oxygen level in the blood to keep it within a specific range, so that there is enough oxygen for the needs of every cell in the body. A person’s blood oxygen level is an indicator of how the body distributes oxygen from the lungs to the cells. It is important for health.
Normal and low oxygen levels in the blood
A normal blood oxygen level ranges between 75 and 100 millimeters of mercury (mm Hg). A blood oxygen level below 60 mm Hg is considered low and may require oxygen supplementation, depending on the physician’s decision and the individual case. When the oxygen level in the blood is too low compared to the average level in a healthy person, it can be a sign of a condition called hypoxemia. This means that the body has difficulty supplying oxygen to all of its cells, tissues and organs.
How is the level of oxygen in the blood measured?
The most effective way to monitor blood oxygen levels is through an arterial blood gas test. For this test, a blood sample is taken from an artery, usually at the wrist. This procedure is very precise, but it can be a little painful. The ABG test can be difficult to perform at home, so a person may wish to perform another test, using a small device called a pulse oximeter.
The pulse oximeter is a small clip that is often placed on a finger, but can also be used on the ear or toe. It indirectly measures blood oxygen by absorbing light through a person’s pulse. Although the pulse oximeter test is easier, faster and less painful, it is not as accurate as the ABG test. Indeed, it can be influenced by factors such as dirty fingers, bright lights, nail polish and poor circulation in the extremities.
For people looking to purchase a pulse oximeter, there is a range of easy to use devices available from pharmacies or online
Symptoms of Low Blood Oxygen
Low oxygen levels in the blood can lead to abnormal circulation and cause the following symptoms:
shortness of breath
high blood pressure
lack of coordination
feeling of euphoria
rapid heart rate
Possible causes of low blood oxygen levels
Hypoxemia, or lower than normal oxygen levels, can be caused by:
an insufficient amount of oxygen in the air
the inability of the lungs to inhale and deliver oxygen to all cells and tissues
the inability of blood to flow to the lungs, pick up oxygen and carry it around the body.
Several medical conditions can contribute to the above factors, including:
heart disease, including congenital heart disease
chronic obstructive pulmonary disease or COPD
interstitial lung disease
acute respiratory distress syndrome
blockage of an artery in the lung, for example due to a blood clot
pulmonary fibrosis or scarring and damage to the lungs
the presence of air or gas in the chest that causes the lungs to collapse
excess fluid in the lungs
sleep apnea where breathing is interrupted during sleep
certain medications, including some narcotics and painkillers.
When to consult a doctor
You should see a doctor if you notice:
severe and sudden shortness of breath
we are short of breath at rest
severe shortness of breath that gets worse during exercise or physical activity
wakes up suddenly with shortness of breath or a feeling of choking
at high altitudes (over 2,400 meters), severe shortness of breath with cough, rapid heartbeat and water retention.
Treatment of low blood oxygen levels
Treatment for low blood oxygen levels includes giving supplemental oxygen. This treatment can be done at home, under the name of home oxygen therapy.
There is a whole range of devices but some of them are considered drugs and require a prescription.
Certain self-care measures can be taken by people to reduce symptoms of shortness of breath and improve overall health and quality of life. These include in particular the following measures
avoiding passive smoking in places where other people smoke
eating a healthy diet rich in fruits and vegetables
Monitor blood oxygen levels
Low blood oxygen levels are not necessarily harmful and can occur in people who are able to recover, or in healthy people when at high altitudes. These people do not need to regularly monitor their blood oxygen levels.
However, people with chronic lung diseases, such as COPD, pulmonary fibrosis, or emphysema, may have lower than normal blood oxygen levels as a result of their disease. These people may need regular monitoring of their blood oxygen levels. People with low blood oxygen levels can also make lifestyle changes, such as not smoking or improving their diet and exercise habits, while being treated with supplemental oxygen.
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