Oxygen Saturation (SpO2)

What is Oxygen Saturation (SpO2)?

First, let’s describe a pulse oximeter and how it works. A pulse oximeter worn on the finger like the CIRCUL™ Ring is a device that measures oxygen saturation (SpO2) in a person’s blood. In other words, it measures the amount of oxygen in the bloodstream. It is usually used in people who may have an unstable blood oxygen content, as can happen in chronic lung diseases. The finger-pulximeter (CIRCUL™ Ring) uses a red and infrared light to measure the oxygen supply in the finger. How is this possible? Because hemoglobin (the part of the blood that transports oxygen) absorbs different amounts of light depending on how much oxygen it transports. As this is an indirect method for measuring oxygen levels, it has proven to be reliable.

Oxygen saturation (SpO2) and CPAP therapy

Low blood oxygen levels are harmful for many reasons. But let’s think about how blood oxygen is related to sleep apnea and CPAP therapy. Low oxygen levels can certainly indicate a serious health problem. People with sleep apnea or an underlying lung disease such as asthma or COPD sometimes have blood oxygen that drops to unhealthy or even critical levels. When people suffer from sleep apnea, their airways close and oxygen is cut off to the brain and bloodstream. Oxygen levels decrease and the brain is stimulated to activate the body. Although this happens unconsciously, the body constantly awakens and interferes with the benefits of deep and restful sleep. This vicious circle is the typical symptom of sleep apnea. The CIRCUL™ Rring can measure oxygen levels to show initial evidence of sleep apnea. Once you have been diagnosed with sleep apnea and you are using your CPAP device, it is important to see if you are getting the full benefit of the therapy. The reason for using a CPAP device is, of course, to keep your airways open to breathe normally and provide oxygen to the blood. Oxygen saturation above 94 is considered normal, while anything below 92 is a signal that you are not taking full advantage of your CPAPtherapy. A pulse oximeter such as the CIRCUL™ Rring can assess the effectiveness of your treatment in a simple and elegant way. Simply attach the CIRCUL™ Ring to one of your fingers and measure your saturation (SpO2)100x per second for up to 16 hours. There are, of course, nuances that need to be understood when reading the results, such as how much time you spend at certain low SpO2 levels. Overall, however, you will get an assessment of whether your CPAPtherapy is successful or should talk to your doctor about optimization.

Oxygen saturation (SpO2) and chronic lung diseases

For COPD or other chronic lung diseases, pulse oximetry (oxygen saturation measurement (SpO2) can be used to determine whether and how much additional oxygen you need.1 In the event of a sudden deterioration of your condition, pulse oximetry can be used to determine whether you should be hospitalized. A study of COPDpatients using pulse oximeters showed that the devices were able to predict very effectively when COPDsymptoms suddenly worsened, known as exacerbations.2 The CIRCUL™ Ring measures your oxygen saturation 100x per second for up to 16 hours. Keep an eye on your oxygen saturation to detect changes at an early stage.

Oxygen saturation (SpO2) in neuromuscular diseases

Neurological and neurodegenerative diseases are functional disorders of the central or peripheral nervous system, which can manifest themselves in different ways depending on the extent and focus. These include multiple sclerosis, a known neurodegenerative disease that affects the central nervous system (brain and spinal cord) with a change in nerve pulse transmission, and amyotrophic lateral sclerosis (ALS), which affects the cells that control muscle movement. Other diseases can affect neuromuscular transition (myasthenia gravis) or the muscles directly (such as muscular dystrophy, polymyositis and dermatomyositis).

Oxygen saturation (SpO2) in heart disease

Heart conditions such as heart attack or heart failure bring many challenges for those affected. Patients often have to live with a weakening of the heart muscle after a heart attack. This so-called heart failure can be counteracted with targeted training. Even if this has limitations, many sufferers go to counselling after such an event and attend heart sports groups. The CIRCUL ring can support you due to the pulse and saturation measurement during this workout, but also during daily activities. A drop in saturation and increase of the pulse can be a first sign of an overload and help you take necessary rest breaks.

What causes sleep disturbances?

In these diseases, the involvement of the respiratory muscles leads to a progressive impairment of respiratory function with serious disabilities. Therefore, in neuromuscular diseases, a regular assessment of lung function must be carried out, including oximetry(oxygen saturation). Oximetry plays an important role in neuromuscular diseases. In such diseases, it is useful to check the extent of respiratory failure under resting conditions. However, sleep oximetry(SpO2 during sleep) is important from the start to check for a possible occurrence of sleep-related disorders. The CIRCUL™ Rring is able to detect prolonged deaturation during sleep, which is otherwise only measurable with complex instruments such as polysomnographs. In the most advanced stages of neuromuscular diseases, apnea also occurs during sleep and causes rapid dearestions of less than 2.5 minutes. By analyzing these types of desaturation (ODI) can help to obtain an initial assessment of the apnea image.


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