What is a Pulse Oximeter and What Are Its Benefits?

When it comes to medical devices, a pulse oximeter is one of the most popular, along with the stethoscope and blood pressure monitors. It’s a compact device provides painless pulse and oxygen monitoring in a few seconds. If you have symptoms like shortness of breath or a heart or lung condition, your physician might recommend you use a pulse oximeter. In this article, learn about the pulse oximeter and its benefits.

What is a Pulse Oximeter?

A pulse oximeter, also known as a pulse ox, is a small, lightweight device used to monitor the amount of oxygen carried in the body. It’s a non-invasive tool that looks like a chip clip or a big clothespin that attaches painlessly to the fingertips, sending two wavelengths of light through the finger to measure the pulse rate and how much oxygen is present in the system. Once it finishes its assessment, the screen will display the percentage of oxygen in the blood coming from the heart and your current pulse rate. Many pulse oximeters are designed to be read by someone facing the user, not the person wearing it.

The purpose of a pulse oximeter is to see if the blood is well-oxygenated. Medical professionals use pulse oximeters to monitor the health of people with medical conditions that affect blood oxygen levels, especially while they are in the hospital. It may be used for these reasons:

  • To see how well lung medicines are working
  • To see if a ventilator is necessary to help with breathing
  • To check if a ventilator is working and to evaluate how helpful it is
  • To monitor oxygen levels during or after surgical procedures that use sedation
  • To determine how effective supplemental oxygen therapy is
  • To check the person’s ability to handle increased activity levels
  • To check if a person momentarily stops breathing while sleeping, like in cases of sleep apnea

Pulse oximetry is essential for checking the health status of a person with any condition that affects blood oxygen levels, such as:

  • Heart attack
  • Heart failure
  • Asthma
  • Lung cancer
  • Anemia
  • Pneumonia
  • Congenital heart disease
  • Chronic obstructive pulmonary disease (COPD)

NOTE:  Be sure to check with your Doctor regarding any ongoing health issues

How does a Pulse Oximeter Work?

When you insert a finger into the pulse oximeter, it beams various wavelengths of light through your finger, while you won’t feel anything. These target hemoglobin, a protein molecule in the blood that carries oxygen. Hemoglobin absorbs different amounts and wavelengths of light depending on its oxygen level. Then, the pulse oximeter will flash a numerical reading indicating the percentage of oxygen saturation in your blood.

To take a reading using a pulse oximeter, here’s what you should do:

  1. Remove any jewelry or nail polish on the finger from which you will get a measure.
  2. Make sure your hand is warm and placed below heart level. You must be relaxed while taking the pulse reading. 
  3. Place the device on your finger.
  4. Keep the device on for as long as needed to monitor the pulse and oxygen saturation. Keep your hands and fingers still – do not move while the device is taking a reading. The device will provide a readout of your heart rate and oxygen saturation level.
  5. Once the reading is over, you can remove the device.

What can Affect the Accuracy of Pulse Oximetry Readings?

  • The pulse oximeter can be in the form of a clip-like device that can be placed on the fingers, earlobes, or toes. Or, it can be a probe with a sticky adhesive designed to be placed on your finger or forehead. Most health technicians use the device on the index fingers or on the middle finger of the dominant hand for the most accurate results.
  • Cold hands may cause lower readings, so warm them up before using a pulse oximeter. Your hands must also be dry and not sweaty.
  • Dark-colored nail polish and tattoos on the fingertips can affect the accuracy of the reading. Try removing them first, or choose a different finger for a more accurate reading.
  • It might be harder to insert your finger in the clip properly if you have very long nails. For better results, the device must be used on a finger with short nails.
  • Thick fingernails can block light penetration and may cause lower readings.
  • Some pulse oximeters may give inaccurate readings to skin with more pigment. FDA found that pulse oximeters may have a higher risk of generating inaccurate readings when used on skin with more pigment. But still, these devices can help you monitor your health. 

Understanding the Results of a Pulse Oximeter

The pulse oximeter measures the oxygen saturation level in your body without using needles or taking a blood sample. The metrics shown on the screen reveal the saturation of your red blood cells with oxygen.

Typically, the saturation number must be more than 89%, as this is the oxygen saturation level needed to keep the cells healthy. An oxygen saturation level of 95% is considered typical for healthy people, and a level of 92% and below may indicate potential hypoxemia, a condition with a low level of oxygen in the blood.

What Happens After?

Once the test is over, the doctor will check the readings available immediately. From there, they can determine if other testing or treatment is needed. If you’re checking how successful your oxygen supplementation therapy is, a low reading might indicate the need for more oxygen.

What to do next after a pulse ox reading depends on your doctor’s advice. If you’re using it at home, they will let you know how often you should take readings and what to do if it goes above or below certain levels.

What are the Risks?

Using a pulse oximeter would not pose any risk to your health and would not hurt once you’re using it. But a few people experience mild skin irritation due to the adhesive used on some types of probes.

It’s also possible that a home monitor would give out a faulty reading or be used incorrectly, prompting a person to seek unnecessary medical care. If you or someone using it shows a very low reading, test it on a healthy person as well to confirm if it’s working correctly. Then, you may discuss it with your doctor.

Monitoring at home using a pulse oximeter should not give you a false sense of security. If you experience physical symptoms, don’t ignore them, even if your oxygen level is fine. You should still call a doctor if you have a high fever, severe shortness of breath, confusion, and other alarming symptoms.

Things to Consider When Buying a Pulse Oximeter

When you’re shopping for a finger pulse oximeter, here are the things to consider:

Type of pulse oximeter

The first thing to determine is the type of oximeter you need for use at home. There are three types: fingertip pulse oximeter, handheld oximeter, and fetal pulse oximeter.

A fingertip pulse oximeter is the recommended type for home use. It has a monitor integrated directly into the clip-on sensor. This is also easy to transport, portable, and practical.

Meanwhile, handheld oximeters and fetal pulse oximeters typically have separate sensors connected by a cable. These devices are more complex, making them less practical for home use. However, they provide more reliable measurements. These types of oximeters are typically more suitable for hospital wards, but if you prefer them and can afford them, you can get one for your home. It’s only a practical choice for people with health conditions needing constant pulse monitoring.

Most finger pulse oximeters in the market are designed for spot checks. If you require consistent and continuous monitoring, ask your pharmacy about medical-grade oximeters to use at home.

Accuracy

When buying any medical equipment, accuracy is the key factor. The readings will give a hint at the current state of your health, and incorrect readings can cause serious repercussions. Unfortunately, there’s no way to check it out when buying, so the best way is to look for reviews and certifications.

Certifications

Make sure to check certifications to ensure the quality and reliability of the oximeter. Some organizations certify standards and quality, which will also help you ensure the accuracy of the device. Some reliable certifications include FDA, CE, and RoHS. It should also meet the ISO standard. Look for these approval stamps on the labels of the pulse oximeters you’re considering.

Size

Most pulse oximeters are designed for average fingertips. If you plan to use a pulse oximeter for the whole family, make sure it fits the fingers of your child or the smallest member of the family. If it’s for an infant, there are pulse oximeters for neonatal or pediatric use.

Readability

There are several features that make reading a pulse oximeter easier, like a multi-directional display, backlighting, anti-reflective glass, and a large number display. You may want to consider these features.

Battery life and durability

The battery life and durability should justify its value even if you are purchasing a budget-friendly pulse oximeter. You would not want to purchase a product that gives up on you after the third use. Plus, the battery life should last long, along with the device giving an accurate reading for years to come.