Understanding Oxygen Saturation
Oxygen saturation (SpO2) measures how much oxygen blood carries in comparison to its full capacity. In other words, it’s an estimation of how much oxygen the hemoglobin in your blood contains compared to how much it could contain. Pulse oximetry devices represent this measurement using a simple percentage. So if your red blood cells contain 95% oxygenated and 5% non-oxygenated hemoglobin, your SpO2 would be 95%. Simple, right?
Now, this is where things get more complicated. It’s possible (and perfectly natural) for your SpO2 to change throughout the day, particularly if you’re transitioning from low-energy to high-energy activities. However, as long as your SpO2 stays within a healthy range amidst these fluctuations, there’s no need for concern.
Changes in activity aren’t the only factors that impact oxygen saturation. There are several adverse conditions and diseases that can
negatively impact SpO2, including asthma and chronic obstructive pulmonary disease (COPD). People afflicted by these health problems often have a lower SpO2 average, necessitating the use of supplemental oxygen and other treatment methods.
Your “Normal” SpO2 Range
According to the Mayo Clinic, normal pulse oximeter readings usually range from 95 to 100 percent. Values under 90 percent are considered low, and indicate the need for supplemental oxygen. This condition is often referred to as hypoxemia, and its symptoms include severe shortness of breath, increased heart rate and chest pain.
For people with chronic lung conditions and other breathing problems, the “normal” SpO2 range of 95% to 100% doesn’t apply. These individuals should always consult with their doctor for information on acceptable oxygen levels for their unique state of health. That being said, here are a few general guidelines on SpO2 for
individuals with acute respiratory issues and chronic diseases:
● In a patient with acute respiratory illness (e.g., influenza) or breathing difficulty (e.g, an asthma attack), an SpO2 of 92% or less may indicate a need for oxygen supplementation.
● In a patient with stable chronic disease (e.g., COPD), an SpO2 of 92% or less should prompt referral for further investigation of the need for long-term oxygen therapy.1
Measuring Your Oxygen Level
Today’s medical experts have access to a wide variety of SpO2 monitoring tools, including finger pulse oximeters. These compact, noninvasive devices attach painlessly to the fingertip and send wavelengths of light through the finger to assess SpO2 and pulse rate. Under the guidance of their physicians, people with heart and breathing problems can use personal finger pulse oximeters to manage their conditions and assess the efficacy of treatment methods. Pulse oximetry can be a useful aid in decision-making, but is not a substitute for a clinical assessment, nor sufficient for diagnosis by itself. Arterial blood gas measurements, obtained by arterial puncture, remain the gold standard for measurement of oxygen saturation.
A personal finger pulse oximeter is designed to be fast, durable and intuitive. All you have to do is place it on any finger and wait a few seconds for it to measure your current SpO2 and heart rate. However, not all pulse oximeters deliver the same level of performance and versatility. Many other brands of finger pulse oximeters are unable to perform with accuracy on patients with low perfusion or dark skin pigmentation, and can’t stand up to repeated daily use. That’s why in-home caretakers and people suffering from respiratory problems count on clinically proven self-monitoring solutions from Nonin.
Nonin Personal Finger Pulse Oximeters
Nonin invented the very first finger pulse oximeter in 1995, making pulse oximetry a viable solution for at-home patient monitoring. Our personal finger pulse oximeters are engineered for daily use in the most demanding monitoring environments, making them suitable for detecting SpO2 and adjusting oxygen flow while exercising, traveling or resting at home. Nonin pulse oximeters provide fast, reliable measurements that empower users and their physicians to make smarter, more confident healthcare decisions.
Count on Nonin for Peerless At-Home Monitoring Solutions
To learn more about Nonin and our award-winning self-monitoring oximetry devices, be sure to contact us today. We can guide you to the perfect at-home monitoring solution for your specific needs.
How to use a Pulse Oximeter at home
Why have I been told to use a pulse oximeter?
You may have been told by your doctor to use a pulse oximeter because you are recovering from COVID-19, or because you are a patient who is at higher risk of suffering with COVID-19. Using a pulse oximeter is a good way of making sure your breathing levels aren't worsening.
What does a pulse oximeter do?
It measures how
fast your heart is beating as well as checking how well you are breathing, it does this by checking how much oxygen is in your blood.
An ideal oxygen level is between 96% and 99% and an ideal heart rate is between 50 and 90 beats per minute (bpm).
The oxygen level may be lower in some people with lung conditions, even when they are feeling well. If you have an existing lung condition, please check with your doctor about what your readings should be.
To view guidance in a language that isn't English, please click here.
How to use a pulse oximeter
Follow these steps to make sure the pulse oximeter gives the correct reading:
- Remove any nail polish or false nails.
- Warm your hand.
- Make sure you have been resting for at least five minutes before taking the reading.
- Rest your hand on your chest at the level of your heart and hold it still.
- Switch the pulse oximeter on and place it on your finger. It works best on your middle or index finger of either hand, it should not be used on your ear.
- The reading takes time to steady. Keep the pulse oximeter in place for at least a minute, or longer if the reading keeps changing.
- Record the highest result once the reading has not changed for five seconds.
- Be careful to identify which reading is your heart rate and which is your oxygen level.
The best way to track your heart rate and oxygen level is by taking a reading three times a day at the same time every day and keeping a diary of each reading.
Download a measurement diary by clicking here.If you are recovering from COVID-19 and need advice on self-isolation and treating COVID-19 symptoms, please visit the NHS website.
The video below will take you through the steps of how to use your pulse oximeter:
What to do if you experience any of the following symptoms
Attend your nearest A&E or call 999 immediately if you have one or more of the following symptoms and tell the operator you may have coronavirus:
- You are unable to complete short sentences when at rest due to breathlessness
- Your breathing suddenly worsens within an hour
- Your blood oxygen level is 92% or less. Check your blood oxygen level again straight away – if it’s still 92% or below, go to A&E immediately or call 999
OR if these more general signs of illness worsen:
- you are coughing up blood
- you feel cold and sweaty with pale or blotchy skin
- you develop a rash that does not fade when you roll a drinking glass over it
- you collapse or faint
- you become agitated, confused or very drowsy
- you have stopped peeing or are peeing much less than usual.
If you have your pulse oximeter, please give the oxygen saturation reading to the 999 operator when you speak to them.
Ring 111 as soon as possible if you have one or more of the following and tell the operator you may have coronavirus:
- You slowly start feeling more unwell or more breathless
- You are having difficulty breathing when getting up to go to the toilet or similar
- If you use the pulse oximeter, your blood oxygen level is 94% or 93% when sitting or lying down and remains at this level after being rechecked within an hour
- You sense that something is wrong (general weakness, severe tiredness, loss of appetite, reduced urine output, unable to care for yourself – simple tasks like washing and dressing or making food)
If your blood oxygen level is usually below 95% but it drops below your normal level, call 111 for advice. Have your diary readings available.
Page last updated: 29th April 2021