Pulse oximeters are critical health monitors. They’re used a lot to check heart and lung health. These handy, portable tools measure your blood’s oxygen saturation (SpO2). Knowing what these results mean is crucial for your health, especially if low oxygen levels are problematic. In this piece, we’ll look at how pulse oximeters work and what the results mean. We will also provide you with a chart to help you understand your readings.

What is a Pulse­ Oximeter?

A pulse oximeter measures the oxygen level in your blood. This no-fuss tool clips onto a finger, ear, or toe and uses light to estimate oxygen levels in your blood. Pulse oximeters are used often in hospitals, clinics, and homes. They’re essential for people with conditions like asthma, chronic obstructive pulmonary disease (COPD), pneumonia and COVID-19. They’re also for people having trouble breathing or those needing extra oxygen.

Pulse Oximeters: How They Work The pulse oximeter uses two light beams to determine oxygen levels. They are: –

• Red light (660 nm): Absorbed by de­oxygenated hemoglobin (hemoglobin without oxygen).
• Infrared light (940 nm): Absorbed by oxygenated hemoglobin (hemoglobin with oxygen). The device compares the light absorbed by both types of hemoglobin to calculate the percentage of oxygenated hemoglobin in the blood (SpO2). This percentage shows how much oxygen is in the blood compared to the total amount it could carry.

Breaking Down Pulse Oximeter Readings Pulse oximeter readings usually give two main measure­ments:

1. Oxygen Saturation (SpO2): Percentage of hemoglobin with oxygen. For healthy folks, SpO2 is generally between 95% and 100%.

2. Pulse­ Rate (PR): Heartbeats pe­r minute. This is measured at the­ same time as oxygen saturation. Below is a chart to help you understand what different SpO2 readings might mean for your health.

From Normal to Critical: Your Pulse­ Oximeter Readings

SpO2 (%)	Description	Possible Implications	Action/Recommendation
95-100%	Normal	Indicates healthy oxygen levels. No immediate health concerns.	No action needed unless other symptoms (e.g., shortness of breath) are present.
91-94%	Below normal, but not critical	Mild hypoxemia (low oxygen levels). May indicate early signs of respiratory distress or underlying health conditions.	Monitor symptoms. Consider consulting a healthcare provider.
85-90%	Low oxygen saturation	Moderate hypoxemia. This is a concerning level, indicating that the body is not getting enough oxygen.	Seek medical attention. Oxygen supplementation may be needed.
80-84%	Very low oxygen saturation	Severe hypoxemia. This is a dangerous level and requires immediate medical intervention.	Immediate medical care is required. Supplemental oxygen and possibly hospitalization may be necessary.
Below 80%	Critical low oxygen saturation	Critical hypoxemia. This is life-threatening and requires urgent medical attention.	Seek emergency medical help immediately. Supplemental oxygen, and possibly ventilation support, may be required.

When is a Pulse Oximeter Reading Normal?

SpO2 is usually between 95% and 100% for a healthy individual. This means nearly all your hemoglobin carries oxygen, and your tissues and organs are getting plenty of it. But, the normal range might change slightly depending on:

• Age: Older adults might have a slightly lower normal SpO2 range
• Altitude: If you’re at a high altitude, normal SpO2 might be lower due to less oxygen.
• Health Conditions: People with ce­rtain ongoing conditions like COPD, asthma, or sleep apnea may have a “normal” SpO2 level lower than 95%. They should ask their doctor about their target oxygen levels.

Low SpO2 Levels: What They Mean Less than 95% on a SpO2 reading means oxygen levels in the blood are lower than usual. While oxygen levels can drop occasionally (like after exercise or during sleep), constant low readings can be a problem. Here’s what different low oxygen levels could mean:

1. 91-94% (Slightly low oxygen level): This level can result from allergies, mild lung infections, or early-stage asthma or COPD. It’s not immediately dangerous but needs attention. If these levels last, extra evaluation is required.

2. 85-90% (Moderately low oxygen level): This level is a worry and might mean serious breathing issues like lung infections, severe COPD, or heart failure. Medical help is needed to find the cause and the proper treatment.

3. Below 85% (Seriously low oxygen level): This is critical. It means the body isn’t getting enough oxygen, which can damage organs if untreated. Things like severe lung infections, acute asthma attacks, or heart failure can cause this level of oxygen deprivation. Immediate medical help is needed, and extra oxygen may be required.

When Should You Use a Pulse Oximeter? Pulse oximeters can be helpful in various situations, like:

• For chronic lung conditions: For conditions like­ asthma, COPD, or sleep apnea, regular checks of your oxygen leve­ls can catch changes and get timely medical help.
• After surgery: After some surgeries, especially for the lungs or heart, pulse oximeters check oxygen levels.
• During/After exercise: Athletes or people with heart or lung conditions can use a pulse­ oximeter during exercise to ensure safe oxygen levels.
• COVID-19 or other lung infections: Low oxygen levels often show severe COVID-19 infection. Keeping track of these levels can spot early signs of breathing trouble.

Things that Might Change Pulse Oximeter Readings While pulse oximeters are usually accurate, certain things can mess up the results, like:

• Nail polish or fake nails: Dark nail polish or fake nails can mess up the sensor’s de­tection of light and give wrong results.
• Cold hands: Cold hands can cause poor circulation, leading to wrong readings. Try warming your hands before testing.
• Movement: Too much movement can affect pulse oximeter accuracy.
• Low blood flow: Low blood pressure or peripheral artery disease might lower blood flow to the extremities, affecting readings.

Pulse Oximeter: How to Use It Here’s how to get accurate pulse oximeter results:

1. Clean and warm hands: Dirty or cold hands can lead to wrong readings.

2. Use on a clean, dry finger: Put your finger into the oximeter, making sure it fits snugly but isn’t too tight.

3. Don’t move: Try not to move while taking the reading.

4. Wait for the result: The tool will display your oxygen saturation perce­ntage (SpO2) and heart rate (PR).

5. Try again if necessary: Take more readings for accuracy. If you’re worried about results, ask a healthcare professional.

Wrapping Up Pulse oximeters are great for monitoring blood oxygen levels, especially for people with heart or lung conditions. Regular checks can spot health problems early and ensure you get help when needed. You can actively work towards good health by understanding pulse oximeter readings and knowing when to seek medical help. Remember, while pulse oximeters give helpful information, they can’t replace a doctor. Always ask a healthcare provider if you have health or oxygen level concerns.