How does the pulse oximeter work?
An oximeter is a non-invasive and painless test that measures oxygen saturation or oxygen levels in the blood.
It can quickly detect even small changes in the efficiency with which oxygen is being transported to the most distant ends of the heart, including the legs and arms.
The oximeter is a small clip-shaped device that attaches to a body part, such as the fingers or earlobe.
It is more common to place a finger and is often used in intensive care settings, such as the emergency room of hospitals. In addition, some doctors, such as pulmonologists, may use it in the office.
In this article, we will know what oximetry is? How does the pulse oximeter work? Find out how the exam works and why it matters. Check out!
How does the finger oximeter work?
A finger oximeter works by shining LED light through the finger. The sensors detect the amount of oxygen in the blood based on how light passes through the finger.
An oximeter is a technology that calculates the results to display a number on the oximeter screen that informs the percentage of oxygen in the blood.
An oximeter also measures your pulse rate.
How does the pulse oximeter work?
A pulse oximeter works by passing a beam of red and infrared light through a pulsating capillary bed.
The device can be connected to a finger, wrist, foot, or any other area where the device can read blood flow.
The equipment works based on the principle that oxygenated blood has a more rich color of red than deoxygenated blood, which is more bluish-purple.
First, the oximeter measures the sum of the intensity of both shades of red, representing the blood fractions with and without oxygen. Next, the device detects the pulse and subtracts the power of the color noticed when the pulse is absent.
The remaining intensity of color represents only oxygenated red blood. This is displayed on the electronic screen as a percentage of blood oxygen saturation.
What is an oximetry test?
Oximetry is a test used to measure the level of oxygen (oxygen saturation) in the blood.
It is an easy and painless measure of how well oxygen is being sent to parts of the body furthest from the heart, such as the arms and legs. First, a clip-like device called a probe is placed on the body part, such as a finger or earlobe.
The probe uses light to measure the amount of oxygen in the blood. This information helps the healthcare professional to decide whether a person needs extra oxygen.
Oximetry is a test used to measure the blood oxygen level.
How is the oximetry exam performed?
Pulse oximetry can be used in outpatient and outpatient settings. In some cases, your doctor may recommend that you have a pulse oximeter for home use.
The oximetry process is as follows:
- Usually, a clip-like device will be placed on your finger, earlobe, or toe. You may feel a small amount of pressure, but there is no pain or pinch.
- A small probe can be placed on the finger or the forehead with an adhesive in some cases.
- You may be asked to remove nail polish if it is being attached to a finger.
- In addition, you will keep the probe for as long as necessary to monitor your pulse and oxygen saturation.
- When monitoring physical activity resources, this will occur during the exercise extension and during the recovery period.
- During surgery, the probe will be attached in advance and removed when you wake up and are no longer under supervision. Sometimes, it will only be used to do a single reading very quickly.
- After the test is complete, the clip or probe will be removed.
What is the average level measured by the oximeter?
Oximetry is generally a very accurate test. This is especially true when using high-quality equipment found in most doctors, offices, or hospitals.
It consistently provides results with a difference of 2%, regardless of what it really is.
If your reading was 82%, for example, your accurate oxygen saturation level can be between 80 and 84%.
However, the quality of the waveform and the individual's assessment must be considered. In addition, factors such as movement, temperature, or nail polish can affect accuracy.
Typically, more than 89% of your blood must be carrying oxygen. This is the level of oxygen saturation needed to keep your cells and your body healthy.
While oxygen saturation below this is not believed to temporarily cause damage, repeated or consistent instances of low oxygen saturation levels can be harmful.
An oxygen saturation level of 95% is considered normal for most healthy people. A group of 92% indicates potential hypoxemia or oxygen deficiency that affects the tissues of the body.
What are the risks and effects of low saturation?
Low levels of oxygen in the blood can result in abnormal circulation and cause the following symptoms:
- Shortness of breath
- Headache
- Restlessness
- Dizziness
- Rapid breathing
- Chest pain
- Confusion
- High blood pressure
- Lack of coordination
- Visual disturbances
- Feeling of euphoria
- Fast heartbeat
Hypoxemia, or oxygen levels below average values, can be caused by:
- Insufficient oxygen in the air
- The inability of the lungs to inhale and send oxygen to all cells and tissues
- The inability of the bloodstream to circulate to the lungs, collect oxygen, and transport it throughout the body.
When is it recommended to use the finger oximeter?
Pulse oximeters are helpful for people who have conditions that affect oxygen saturation.
For example, a sleep specialist may recommend a pulse oximeter to monitor the nighttime oxygen saturation level of someone with suspected sleep apnea or severe snoring.
Pulse oximetry can also provide feedback on the effectiveness of respiratory interventions, such as oxygen therapy and ventilators.
Some doctors use a pulse oximeter to assess the safety of physical activity in people with cardiovascular or respiratory problems or may recommend that a person use a pulse oximeter during exercise.
A doctor can also use pulse oximetry as part of a stress test. Some hospitals also use pulse oximeters for particularly vulnerable patients.
For example, babies in neonatal intensive care units can use pulse oximeters, alerting the team to a drop in oxygen saturation.
When is it recommended to use the pulse oximeter?
Pulse oximetry can be used to check that there is enough oxygen in the blood. This information is needed in many types of situations.
Blood oxygen saturation can be used:
- During or after surgery or procedures that use sedation
- See how the lung drugs are working
- To check a person's ability to cope with increased activity levels
- See if a ventilator is needed to help breathe or to see if it is working well
- Check if a person has moments when breathing stops during sleep ( sleep apnea ).
Pulse oximetry is also used to check the health of a person with any condition that affects blood oxygen levels, such as:
- Heart attack
- Cardiac insufficiency
- Chronic obstructive pulmonary disease (COPD)
- Anemia
- Lung cancer
- Asthma and Pneumonia
There is a reason why pulse oximeters are widely used in medical facilities, medical clinics, and even patients' homes.
They generally provide accurate and on-site readings, which is a valuable resource, especially in emergencies.
Your doctor may have other reasons for advising you to measure the level of oxygen saturation in your blood.
What are the advantages of using a pulse oximeter?
Pulse oximeters are helpful for people who have special health conditions that affect oxygen saturation.
For example, a sleep specialist may recommend an oximeter to monitor the nighttime oxygen saturation level of someone with suspected sleep apnea or severe snoring.
Oximetry can also provide feedback on the effectiveness of respiratory interventions, such as oxygen therapy and ventilators.
Some doctors also use an oximeter to assess the safety of physical activity in people with cardiovascular or respiratory problems or may recommend that a person use a pulse oximeter during exercise.
A doctor can also use oximetry as part of a stress test. Some hospitals also use pulse oximeters for particularly vulnerable patients.
For example, babies in neonatal intensive care units can use pulse oximeters, alerting the team to a drop in oxygen saturation.
What are the risks of pulse oximetry?
All procedures have some risks. The risks of this procedure can include:
Your risks can vary depending on your general health and other factors. So first, ask your doctor which risks apply most to you. Then, talk to him about any concerns you have.
Errors in pulse oximetry?
Although a SpO2 pulse oximeter provides reliable data, there is no guarantee that it is error-proof.
It can provide inaccurate results in excessive movement or when it is done in an environment with ambient light and in patients with enamel on the fingers.
It is also important to note that an oximeter cannot differentiate between different forms of hemoglobin.
For example, carboxyhemoglobin is already 90% oxygenated and 10% desaturated, leading to overestimated results.
A seemingly simple device, like the pulse oximeter, can save a life.
In the case of a low oxygen saturation measurement, which measures below the normal 95 to 100% range, look for visible signs of breathing difficulty and seek medical help immediately.
What happens after pulse oximetry?
When the test is over, your doctor will have readings available immediately. This will help them determine whether further tests or treatments are needed.
If you evaluate the success of your oxygen supplementation therapy, for example, a reading that is still on the underside may indicate the need for more oxygen.
You can probably go home after the test unless you are in the hospital for another reason. In addition, you can return to your regular diet and activities as instructed by your doctor.
Your doctor will be able to tell you what the next steps are.
If you use a pulse oximeter at home, they will tell you how often you should take your readings and what to do if they are above or below certain levels.
What is the difference between a desktop and a portable oximeter?
Table oximeters usually are used in hospitals and intensive care centers as they operate on battery or by a direct power supply from the mains.
These devices are easily transportable.
Already oximeters known as portable or finger are easily accommodated, fitting in a lab coat pocket, for example.
They are generally more common for healthcare professionals and people who need frequent monitoring of the blood oxygen saturation level.
Conclusion
Oximeter devices are non-invasive and pose no serious risk. However, some people experience minor irritation, including tenderness and redness of the skin.
If attached too tightly and used for an extended period, pulse oximeters can cut off oxygen from surrounding vessels.
Anyone who experiences numbness, tingling, or a change in skin color should immediately notify a doctor.
The main risk of oximetry is a false reading. The accuracy of pulse oximeters depends on correct adjustment, and small changes in their positioning can produce an inaccurate reading.
A person who rolls over while sleeping may loosen the device, causing a false alert.
Oxygen saturation can also dip for short periods due to other factors, such as a change in sleeping position or a sharp breath. An oximeter gives an alert even when the drop is temporary and harmless.
So you must follow your doctor's instructions to use the oximeter and get a good reading.
Having an accurate and easy-to-read device becomes crucial for health professionals to be sure that everything is going well.
All information and articles available on this site are for educational purposes only. The information given here should not be used without any expert advice for the diagnosis or treatment of any health related problem or disease. Always seek the advice of a qualified doctor for medical examination and treatment.