How to Read a Pulse Oximeter Like a Boss
Steven Cumper
Published in MedShop Blog
0 min read
March 21, 2024
While the pulse oximetry market is full of options well in excess of that number, what we carry is what users tend to want after considering all their options.
In short, we’ve done all the heavy lifting for you. Now you only have to pick the oximeter that works for your needs. That picking is where most folks get stuck.
Accurately using a pulse oximeter may seem at first like a scary proposition, especially if one’s life depends on accurate readings, but it’s really not that difficult. In fact, by the time you finish reading this blog, you’ll see that there’s not much to the matter.
What follows are the broad strokes dividing the three biggest brands and their oximeters, but first a note on the general use…
How Does a Pulse Oximeter Read Oxygen Levels? – General Use
Here’s the good news: Reading oximeters regardless of brand is easy. Even the most non-technical users can master turning on any device, putting it on and reading the data.
Each has a probe, the part that goes non-invasively on the finger, and the pulse oximeter measures oxygen saturation levels (SpO2) and a heart rate (BPM). They may also measure arterial blood gas and identify things such as carbon monoxide or carbon dioxide, the number of red blood cells, and a range of health conditions related to pulse rate, blood flow, and blood pressure.
They do this using infrared light, providing a fast and accurate picture of the patients blood oxygen level and blood oxygen saturation by measuring the light the changes of light absorption in the blood stream.
What Do Pulse Oximeter Numbers Mean?
Pulse oximeter numbers provide information about oxygen saturation (SpO2) and heart rate, and below, we look at what the associated numbers mean when reading a pulse oximeter.
Oxygen Saturation (SpO2)
Oxygen saturation is expressed as a percentage and represents the amount of haemoglobin in the blood that is carrying oxygen. The normal range for oxygen saturation in a healthy individual is typically between 95% and 100% and reading below 90% is generally considered low and may indicate hypoxemia, otherwise known as a low level of oxygen in the blood. In certain individuals with chronic lung diseases, a target range of 88% to 92% may be appropriate.
It's important to note that individual circumstances may influence the target range. For example, individuals with pre-existing respiratory conditions may have a baseline oxygen saturation level lower than 95% but still be within their normal range. Additionally, healthcare professionals consider other factors such as overall health and medical history when interpreting SpO2 readings.
Heart Rate
Pulse oximeters also measure heart rate, which is the number of times the heart beats per minute. The normal resting heart rate for adults is typically between 60 and 100 beats per minute. However, heart rate can vary based on factors such as age, fitness levels, and underlying health conditions. It's essential to compare heart rate readings with an individual's baseline or consult a healthcare professional for personalised assessment.
The combination of oxygen saturation and heart rate readings from a pulse oximeter provides valuable information about an individual's respiratory and cardiovascular health. However, rapid changes in oxygen saturation or heart rate, as well as symptoms such as shortness of breath, chest pain, or dizziness, mean you should seek medical attention immediately.
How to Use Your Pulse Oximeter
For accurate and reliable readings, we advise monitoring your oxygen levels two or three times daily, particularly when experiencing symptoms of illness. We recommend following these steps diligently to ensure the most precise measurements possible:
- Remove nail polish, false nails, or jewelry from your finger.
- Wash hands with warm water and dry thoroughly.
- Sit upright, having rested for five minutes.
- Turn on the device, attach the clip to your thumb or middle finger, ensuring fingertip contact with the sensor. Your palm should face down, allowing clear viewing of the screen.
- Keep hands and fingers still, breathe normally for a minute.
- Record readings in your symptom diary.
Accuracy of Pulse Oximeters
Pulse oximeters' accuracy can be influenced by various factors such as:
- Nail polish, artificial nails, or tattoos
- Variability in quality and accuracy among different models
- Darker skin tones
- Changes in sensor placement
- Consistent use of the same finger for measurements (preferably the middle finger of your dominant hand)
- Regular cleaning of the device and ensuring sufficient battery power
We also recommend that regular calibration and proper usage are essential for obtaining reliable results.
Limitations in Using Pulse Oximeters
While pulse oximeters are valuable tools for monitoring oxygen saturation levels, blood pressure, and heart rate, it's important to be aware of their limitations. Below, we look at some of the common limitations you should be aware of before investing in this type of medical equipment.
Accuracy
Pulse oximeters may not always provide completely accurate readings. Factors such as poor circulation, cold extremities, nail polish, false nails, or excessive movement can interfere with the sensor's ability to obtain accurate measurements. In certain cases, the device may provide false readings or fail to detect low oxygen levels, leading to potential misinterpretation.
Delayed Response
Pulse oximeters may not provide real-time readings, especially during sudden changes in oxygen levels or rapid fluctuations in heart rate. There might be a slight delay in reflecting the actual changes, which can be critical in certain medical emergencies.
Measurement of Peripheral Oxygen Saturation
Pulse oximeters measure oxygen saturation in peripheral capillaries (SpO2), which may not always correlate perfectly with arterial oxygen saturation (SaO2). In certain medical conditions, such as circulatory or vascular disorders, the readings may not accurately represent the actual oxygen levels in the arterial blood.
Inability to Measure Other Parameters
Pulse oximeters provide information about oxygen saturation and heart rate, but they do not measure other vital parameters such as respiratory rate, blood pressure, or carbon dioxide levels. A comprehensive assessment of a patient's health often requires additional measurements and clinical evaluation.
User Interpretation
Interpreting pulse oximeter readings requires knowledge and understanding. Inaccurate interpretation of the readings or failure to recognise other clinical signs and symptoms can lead to misdiagnosis or delayed treatment.
Medical Conditions and Special Populations
Health conditions, such as anaemia, certain types of lung diseases such as the coronavirus, that may lead to shortness of breath, or carbon monoxide poisoning, can affect the accuracy of pulse oximeter readings. Additionally, special populations like infants with small fingers, individuals with darker skin pigmentation, or patients with tremors or excessive movement may experience challenges in obtaining accurate readings.
It's crucial to remember that home use pulse oximeters should be used as a complementary tool and not as a sole diagnostic or treatment decision-maker. If there are concerns about oxygen levels or any symptoms, you should consult your healthcare provider for a comprehensive evaluation and interpretation of the results.
If you still have questions, we want to hear from you. Please contact us today. We want to help you find the perfect oximeter for your needs by answering any questions you may have.
Pulse Oximetry Options
Biolight Oximeters
Guandong Biolight Meditech Co., Ltd, otherwise known simply as Biolight, is a Chinese medical supply company.
Since 1993, they have specialised in patient monitoring systems, from multi-perimeter monitors to simpler tools like pulse oximeters.
What Biolight brings to the oximeter table is affordable and reliable innovation.
For many organisations working with tight budgets, Biolight is the perfect no-compromise solution.
Their line of oximeter tools spans from their 2.4-inch monitor to their cute pediatric finger pulse monitor, which is awesome because it looks like a bird. Kids love it.
Biolight Finger Pulse Oximeters
Finger pulse oximeters like the Biolight Finger Pulse Oximeter SP02 Monitor are easy to use and so accurate—perfect for real-time spot-checking of oxygen levels.
Assuming the user has already charged the two AA batteries, one only need to apply the probe to the finger, press the button to turn on the monitor, and then wait for results.
These oximeters work in any ambient light condition. This is the same technology in the pediatric version mentioned above.
Biolight Handheld Oximeters
In the Medshop Australia catalogue, we have one handheld Biolight oximeter, the M800 Patient Monitor.
Biolight designed this model to work with rechargeable AA lithium batteries which charge when placed in the stand, but that feature does not come with the standard unit shipped from us.
Unlike Biolight’s finger oximeters, this device has a more clinically accurate reading, and therefore should only be used by professionals. The display includes oxygen saturation, pulse, and an accurate pleth chart.
This doesn’t mean it’s a tough device to use. Once it’s charged and on, one only needs to attach the probe to a patient’s finger to get an accurate reading.
The display conveniently rotates from landscape to portrait views by simply turning the device. Where the device separates from the models above is the menu and navigation buttons, which allow the user to adjust the settings for sound, display, and readings.
Most will use this menu to change the device from spot-checking to continuous modes. It requires entering the passcode, “789” to access that menu.
Heal Force Prince Oximeters
In their English-speaking markets, the Heal Force line of pulse oximeters bears the name Prince as part of each model name.
The Prince line of oximeters may not always be the cheapest of the bunch, but they do promise an easy and accurate reading for a variety of users.
Heal Force’s Prince oximeters are accurate, functioning in both clinical and home-use situations. They are so easy to use, one only need insert a finger to activate them and receive a reading.
Prince Oximeters are versatile enough to work with children’s and adult’s fingers by simply attaching a probe. The oximeter recognises and adjusts for the difference to give an accurate reading every time.
They also offer unique features like anti-motion technology for patients who suffer from disorders like Parkinson’s, and they offer rugged oximeters, designed to handle the impact being of being dropped.
Heal Force Handheld Pulse Oximeters
There is only one handheld oximeter in the Medshop Australia catalogue from Prince, but it’s a phenomenal device, the Prince-100F.
It’s simple enough to be used at home, but rugged and accurate enough that clinicians will appreciate it too. To use it, one only need to attach the correct probe for adult, child or baby, and power up the handheld.
The large dot-matrix LCD display with backlight makes this device super easy to read, and it displays critical data for analysis.
Using Heal Force’s anti-motion control, it gathers data beyond SpO2 and BPM, offering a pleth chart or perfusion index display as is the preference of the user.
What the handheld can do that the finger oximeters cannot is store data, in this case for up to 70 hours. For more advanced users, it can also integrate with data management software to track changes over time.
The 100F is cord-free but can operate with the optional external cord as well.
Rossmax Oximeters
Easy to use and understand just like the rest of the oximeters on this blog, what truly separates the Rossmax from the rest is the introduction of their ACT technology.
ACT stands for Artery Check Technology, which means the oximeters from Rossmax process SpO2 levels to determine arterial stiffness.
Their oximeters then classify the arteries into one of six categories in addition to measuring the oxygen volume.
This is key for early detection of arteriosclerosis, peripheral circulation disorders, and other cardiovascular diseases as well as hypoxemia and low oxygen levels.
Rossmax Handheld Pulse Oximeters
Similar to the Heal Force line, Medshop Australia carries one Rossmax handheld pulse oximeter, the SA210. It’s the most affordable handheld oximeter on our list, making it the first choice of individuals and clinics on a budget.
Use of the device is as easy as affixing the correct probe, all three we’ve included with each handheld, and turning it on.
The Rossmax handheld offers more features than the finger oximeters but is as easy to use with a similar simple LCD display, reporting SpO2 and BPM metrics.
More advanced users will appreciate the ability to toggle off the alarm feature, which may be more appropriate for clinical use. It can even run silently if necessary by simply pressing a mute button.
Rossmax Finger Pulse Oximeters
While Rossmax may not be the least expensive brand of oximeters in the Medshop lineup, the Rossmax name and reputation make it one of the most purchased brands of the bunch.
The two finger oximeters we carry, the SB100 and the SB220, both offer Rossmax reliability and ease of use, making either a good choice for individual use. they both come with one button design, the large on-button.
Once turned on and applied to the finger, both oximeters do all the work. The SB100 offers a no-nonsense LCD display, packaged in a sturdy design, which delivers accurate spot-check metrics.
Both the SB100 and the SB220 offer Rossmax ambient light prevention design, so readings have a smaller margin of error.
The SB220, however, comes with an LED display, allowing it to rotate 360 degrees depending on the viewing angle. Reading an oximeter was never easier than with the SB220.
Author: Steven John Cumper, B.App.SC. (Osteo.), M.Ost., is a businessman with a strong foundation in biomedical science and osteopathic medicine, who founded and led Medshop to international success, culminating in its acquisition by the Bunzl Group in September 2021, where he continues to serve as Managing Director (Medshop Group).
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