What is a good oxygen level reading

We measure blood oxygen levels in our bodies to ensure that everything is working as it should be. Your blood oxygen levels indicate the amount of oxygen that your red blood cells are carrying around your body, if the levels dip too low you can become unwell.

Table of Contents Show

What can affect my oxygen levels?
How can you measure blood oxygen levels?
What does my Sp02 reading mean?
Can I check my blood oxygen (SP02) levels at home?
What is a normal blood oxygen level?
Blood oxygen levels – What’s normal?
Hypoxemia and Hypoxia
What is an oximeter?
How can we use an oximeter at home?
Are oximeters accurate?
Can oximeters be used for babies?
Smartwatches to check oxygen levels – Is it an option?
Oximeter reading – When to go to the hospital?
What is a dangerously low oxygen level?
What is normal oxygen level by age?
Is 92 a good oxygen level?
At what oxygen level should you go to the hospital?

What can affect my oxygen levels?

There are various factors that can affect the levels of oxygen in your body, some are ongoing conditions, such as emphysema or lung damage, and some are more circumstantial, such as having a chest infection, or being at a high altitude.

How can you measure blood oxygen levels?

There are two main ways to measure oxygen levels in the blood – taking a sample of blood from your body with a needle (usually in the wrist or the earlobe), or using a pulse oximeter.

You can use a Finger Pulse Oximeter to measure your blood oxygen at home – see below.

What does my Sp02 reading mean?

Click here or enter your readings below:

Reasons that blood oxygen saturation can drop include:

Suffocation
Choking
Infections and viruses, such as pneumonia or Coronavirus (COVID19)
Drowning
Diseases, including emphysema, lung cancer, and COPD
Heart failure or an ongoing heart condition
Stroke
Allergic reactions
Sleep Apnea
Being put under a general anaesthetic

Can I check my blood oxygen (SP02) levels at home?

Yes! Using a Finger Pulse Oximeter, which is a small device that is attached to your finger to measure the amount of oxygen in the blood travelling round your body. The Oximeter takes an SpO2 reading – an estimation of the amount of oxygen in your blood. Find out how to use a pulse oximeter.

Oxygen is carried around your body in your red blood cells by a molecule called haemoglobin. A finger pulse oximeter measures how much oxygen the haemoglobin in your blood is carrying. This is called the oxygen saturation and is a percentage (scored out of 100).

What is a normal blood oxygen level?

An SpO2 reading of 96% or more is generally considered to be a normal oxygen level. An SpO2 reading of 92% or less could indicate that your blood is poorly saturated. Insufficient saturation can cause issues such as chest pain, shortness of breath and increased heart rate.

Oxygen levels of 92% or less are considered abnormally low and usually would be classed as a medical emergency. Please seek urgent medical attention if your levels are this low, or have dropped 5% compared to your usual baseline, eg by attending A&E or ringing 999 immediately.

Who should be most concerned about their blood oxygen levels?

People who suffer from a lung condition, such as COPD may need to monitor their SpO2 levels more often as they may have a lower blood oxygen level than a healthier person. Monitoring levels can help detect problems.

People suffering from respiratory conditions such as asthma, or cardiovascular conditions may also benefit from more regular monitoring of their blood oxygen levels for the same reasons.

If you are thought to be suffering from an infection or virus such as pneumonia or the most recent Coronavirus outbreak, you will have your blood oxygen levels tested and monitored. This is to help determine the severity of the infection, and to monitor your oxygen levels if you may need or are receiving treatment. See more about what happens when you are tested for Coronavirus in this video.

The Kinetik Approved Finger Pulse Oximeter is a compact device that makes taking an SP02 reading at home very quick and easy. This Oximeter is a certified class lla medical device that can be safely used in or out of your home to check your blood oxygen levels and pulse rate. It comes with a handy lanyard and batteries for portable and convenient use and is ultra-simple to set up.

The COVID-19 pandemic has changed how we live and breathe. While the vaccines give us hope, the emergence of new virus variants is a constant cause for concern. As such, we are encouraged to stay vigilant towards critical COVID-19 symptoms that may need immediate medical attention.

While you may be able to identify the more common symptoms of COVID-19, it has been reported that sometimes oxygen levels may start to drop even before any symptoms would appear. Oximeters are devices that can help track your oxygen levels and detect cases with “silent pneumonia”, one of the most serious consequences of COVID-19.
In this article, we cover the significance of blood oxygen levels and other important facts you need to know about oximeters.

Blood oxygen levels – What’s normal?

Blood oxygen level is the amount of oxygen your blood carries. The levels indicate how well your body distributes oxygen throughout the body and hence can give an indication of your general health.

As per the World Health Organization’s definition, an oxygen level between 95 – 100% is normal. Levels under 94% should be evaluated by a doctor, while levels below 90% are considered a clinical emergency and require immediate medical attention.

When you’re exposed to COVID-19, your lungs are one of the major organs to be affected. Damage to the lungs can cause the oxygen in your blood to drop to dangerously low levels, even when you feel generally well, or present no other symptoms of the virus. This is known as “silent pneumonia” and if left untreated, can lead to very serious consequences.

Hypoxemia and Hypoxia

Hypoxemia refers to the low level of oxygen in your blood. It can cause hypoxia (low oxygen in your tissues), which means not enough oxygen is making it to the cells in the body that need it.

Fatigue or shortness of breath, bluish colouring in the face and lips, restlessness, chest pain, and a rapid pulse rate are some typical symptoms of low blood oxygen in your body. But in some cases, you may show no symptoms. Silent hypoxia occurs when a pulse oximetry test on a person with no symptoms of low blood oxygen, results in an oximetry reading that is lower than what is considered normal. This occurrence has recently been observed in large number of individuals diagnosed with COVID-19. Hypoxia, if not detected early, can cause serious damage to your major organs and lead to the disease worsening.

Apart from COVID-19, asthma, heart disease, and chronic obstructive pulmonary disease (COPD) are some other conditions that can impact blood oxygen levels.

What is an oximeter?

An oximeter is a portable device that can be used to check blood oxygen levels by looking at how much light is absorbed by your blood. The device works by shining 2 lights (one red light and one infrared light) through your fingertip. Absorption of these lights can differs significantly between blood loaded with oxygen and blood lacking of oxygen. Blood loaded with oxygen absorbs more infrared light and lets more red light pass through it. Blood with not enough oxygen tends to absorb more red light and lets more infrared light pass through it. It is fast, simple and non-invasive (needle-free).

During COVID-19 times, using an oximeter at home can help you check your blood oxygen levels and indicate when you need prompt medical attention.

How can we use an oximeter at home?

An oximeter is a user-friendly device, with a small clip that can be placed at the end of your finger. In some cases, it is also placed on the toe or earlobe. To achieve the best results, it is recommended to place the oximeter on your right hand’s middle finger.

Before using an oximeter, make sure your hand is warm, relaxed, and held in front of your chest, below the level of your heart. You should avoid movement while conducting the test. You should also remove any fingernail polish as it may interfere with your results.

Keep the oximeter on your finger and wait for the reading to stabilise, which should take 10 – 30 seconds. The blood oxygen level, also known as oxygen saturation (SpO2), will be displayed on the screen.

When using an oximeter at home, you should always keep a record of your oxygen levels in case you need to show it to your doctor. These records can help you easily track changes and highlight any abnormal values. Along with the oximeter readings, it is important to look out for the symptoms of low oxygen levels.

Are oximeters accurate?

Oximeters may not be always accurate, but the level of inaccuracy may be small. Several factors such as poor circulation, skin thickness, smoking and fingernail polish can affect accuracy.

Can oximeters be used for babies?

You may be concerned when considering tests on babies, however, oximeters are safe to be used on babies. Oximetry is a non-invasive and painless (needle-free) method. There is also no radiation involved.

Oximeters are a critical tool in determining oxygen needs in newborns, especially those with medical conditions such as congenital heart defects and respiratory abnormalities. However, adult oximeters may not be the right dimensions for use on a baby.

Paediatric pulse oximeters are generally used for children. They work the same way as adult oximeters but the paediatric device is designed to fit smaller fingers. In infants and young children, handheld paediatric oximeters will be used in which probes are placed on the child’s palm or foot. If you have concerns about their oxygen levels, you should always consult your child’s paediatrician. Oximeter readings between 95 – 100% are in the normal range for healthy children.

Smartwatches to check oxygen levels – Is it an option?

After reading about oximeters, you may be wondering if they can be replaced with smartwatches.

Though several smartwatches are equipped to measure blood oxygen levels, readings on smartwatches are not always accurate. Smartwatches cannot check blood oxygen levels to medical levels of accuracy because the sensors are just not designed or tested for medical use and medical-grade oximeters are much more reliable.

Placement or the way you wear the smartwatch can also affect its accuracy. In pulse oximetry, transmission mode is used – oximeters are clipped onto your finger and the blood flow is close to the surface. Light emitted on one side of the oximeter travels to a sensor on the other side. But, in smartwatches, reflectance approach is used – both the light source and sensor are on one side of your wrist and therefore relies on the light that bounces back. The blood vessels in the wrist can also complicate the readings.

Oximeter reading – When to go to the hospital?

Patients with moderate to critical COVID-19 associated pneumonia have a high risk of low oxygen levels. Advanced age, underlying conditions such as diabetes, heart disease and obesity are other risk factors.

If you are managing COVID-19 symptoms at home, always consult a doctor if your blood oxygen level drops below 95% or you notice the typical symptoms of low blood oxygen.

Article reviewed by Dr Joy Lim, acting medical director at IHH Healthcare Singapore

References

Comparison of SpO2 values from different fingers of the hands. Published on 2015 Sep 29. Retrieved on 2 Jul 2021 from https://pubmed.ncbi.nlm.nih.gov/26543696/

Pulse Oximeter Accuracy and Limitations: FDA Safety Communication. Published on 2021 Feb 19. Retrieved on 2 Jul 2021 from https://www.fda.gov/medical-devices/safety-communications/pulse-oximeter-accuracy-and-limitations-fda-safety-communication

Accuracy and Reliability of Commercial Wrist-Worn Pulse Oximeter During Normobaric Hypoxia Exposure Under Resting Conditions. Published on 2020 Jul 7. Retrieved on 2 Jul 2021 from https://pubmed.ncbi.nlm.nih.gov/32633688/

Oxygen saturation ranges for healthy newborns within 24 hours at 1800m. Published on 2017 Apr 19. Retrieved on 2 Jul 2021 from https://fn.bmj.com/content/102/3/F266

Why can't your fitness tracker tell you if you have coronavirus? Published on 2020 May 6. Retrieved on 2 Jul 2021 from https://www.wired.co.uk/article/blood-oxygen-spo2-covid-wearables

Hypoxia and Hypoxemia. Published on 2020 Jun 14. Retrieved on 2 Jul 2021 from https://www.webmd.com/asthma/guide/hypoxia-hypoxemia.

Answers to Parent Questions about Pulse Oximetry Screening for Newborns. Retrieved on 27 Jul 2021 from https://www.childrenscolorado.org/doctors-and-departments/departments/heart/programs-and-clinics/critical-congenital-heart-disease-screening-program/answers-to-parent-questions/

What is a dangerously low oxygen level?

People should contact a health care provider if their oxygen saturation readings drop below 92%, as it may be a sign of hypoxia, a condition in which not enough oxygen reaches the body's tissues. If blood oxygen saturation levels fall to 88% or lower, seek immediate medical attention, says Dr. Lutchmansingh.

What is normal oxygen level by age?

Oxygen saturation levels (SpO2) between 95 to 100 percent are considered normal for both adults and children (below 95% is considered abnormal). People over 70 years of age may have oxygen levels closer to 95%. Normal oxygen saturation levels (SpO2) are between 95 to 100 percent for both adults and children.

Is 92 a good oxygen level?

A normal oxygen saturation level ranges between 95 percent and 100 percent. Saturation levels may be somewhat lower and considered acceptable if you have a lung disease such as COPD or pneumonia. Levels may also be lower if you live in an area with higher elevation.