Oxygen enters your bloodstream after passing through your lungs. Your blood oxygen level is a measure of the amount of oxygen you have in your body. In order to function properly, your body requires a certain amount of oxygen, and low blood oxygen levels can result in serious health issues.
What does blood oxygen level mean?
It is the amount of oxygen in your blood that determines your blood oxygen level (blood oxygen saturation).
A constant supply of oxygen is necessary for the proper functioning of our bodies. When you inhale (breath), oxygen enters your body through your nose or mouth and travels through your lungs to reach your blood. The oxygen in your blood then travels to all of your cells, where it is used by every cell. O2 is essential for the efficient production and utilization of all the body’s vital processes, including digestion and even thinking.
When your cells consume oxygen, carbon dioxide is produced. The carbon dioxide is then transported back to your lungs by your bloodstream, where you exhale it out of your mouth or nose.
Because low blood oxygen levels (hypoxemia) can cause a variety of serious conditions and damage to various organ systems, including the brain and heart, your body keeps a close eye on how much oxygen saturation is present in your blood. The lungs and/or circulation may not be working properly if your blood oxygen levels are low. There are ways to increase blood oxygen levels naturally.
What is a blood oxygen level test?
Pulse oximetry and a blood draw are the two most common methods for measuring or testing blood oxygen levels (using an oximeter). An oximeter can only tell you so much about your blood oxygen levels.
Oxygen level blood draw test
You can have your blood oxygen level measured by a healthcare provider as part of a larger test called an arterial blood gas (ABG). The oxygen and carbon dioxide levels in your blood are measured using an ABG test. The pH balance in your blood is also checked as part of the test. A blood acid level that is either too high or too low can be hazardous to your health.
You can also use a pulse oximeter to measure your blood oxygen saturation levels by placing a small clip on your finger or toe. The SpO2 level and heart rate are the only two things an oximeter reading can tell you about your health. If someone’s blood oxygen level is too low, this is an easy and safe way to check.
In hospitals, pulse oximeters are used frequently by healthcare workers. Alternatively, you can purchase a pulse oximeter and use it at home; these can be found in pharmacies, as well as other retail establishments and online.
Why do I need to have my blood oxygen level tested?
If you’re experiencing any of the following acute (i.e., sudden and serious) symptoms, your doctor may order a blood oxygen level test.
- In the event that you’re struggling to breathe. (If a newborn baby is having difficulty breathing, a blood oxygen test may be required.)
- Injuries to the head or neck, such as a concussion, can cause breathing problems.
- If you have coronavirus disease (COVID-19).
- In the event of pneumonia.
- Take care of yourself if you are suffering from carbon monoxide poisoning.
- If you’ve been injured by smoke inhalation.
- If you’ve had multiple bouts of vomiting and/or nausea.
- In the event of a drug overdose.
Patients with any of the following conditions may also be tested for blood oxygen levels to ensure that their treatment is working properly:
- Chronic obstructive pulmonary disease (COPD).
- Cystic fibrosis.
- Heart disease.
It’s common for a hospital to monitor your blood oxygen level to ensure that you’re receiving the correct amount of oxygen while on oxygen therapy.
How can I increase my blood oxygen level?
There are ways to increase blood oxygen levels naturally such as:
Breathing in the fresh air: By increasing the amount of oxygen your body takes in, such as by opening windows or taking a walk outside, your blood oxygen level rises.
Quitting smoking: Just a few days after you quit, your circulation will begin to improve. During the first one to nine months, you will notice a decrease in your breathlessness. To help your body absorb more oxygen, you should focus on both of these factors at the same time.
Practicing breathing exercises: Deep belly breathing and other simple breathing exercises can open your airways, allowing more oxygen into your bloodstream.
Check your blood oxygen levels with a pulse oximeter at home to see if these natural methods of increasing oxygen intake are effective for you.
If you have a serious illness like pneumonia or carbon monoxide poisoning, however, these home remedies may not be sufficient to raise your blood oxygen level to a safe level. If you notice any of the symptoms of hypoxemia, you should seek medical attention right away.
Who performs a blood oxygen level test?
Respiratory therapists typically draw blood from an artery in your wrist to perform blood oxygen level tests that are part of arterial blood gas tests. Once the sample has been collected, it is either processed on-site by the respiratory therapist or quickly transported to a lab where it is processed by medical laboratory scientists.
A pulse oximeter can be used by any healthcare provider to measure your blood oxygen saturation. A pulse oximeter can also be used at home on you or another person.
What happens before a blood oxygen level test?
Before drawing blood from an artery in your wrist, a respiratory therapist may conduct an Allen test, which is a blood circulation test. The Allen test entails making a fist and holding it high in front of your face. After a few seconds, your provider will apply pressure to the arteries in your wrist. This simple test checks to see if both of your wrist’s arteries are open and working properly.
You may be asked to wait up to 20 minutes before the blood is drawn if you’re using supplemental oxygen. A “room air test” is what you’re doing here. If you can’t breathe on your own, your doctor won’t conduct this test.
What should I expect during a blood oxygen level test?
One of your veins is most commonly used to draw blood for most blood tests. A respiratory therapist will draw blood from one of your arteries to perform a blood oxygen level test as part of an arterial blood gas test. This is due to the fact that blood from an artery contains more oxygen than blood from a vein.
As the name suggests, a sample is typically taken from the radial artery in your wrist by an experienced respiratory therapist. An artery in your elbow or groin may be used to obtain a sample. Blood oxygen levels can be measured by drawing a sample from a newborn’s heel or umbilical cord.
An artery blood sample is usually more painful than a vein blood sample, but it is possible to get a blood sample from both. nerve-rich arteries make this possible because they penetrate deeper than veins. When a respiratory therapist draws blood from your artery, you may feel light-headed, dizzy, or nauseated.
Blood is drawn for a blood oxygen level test in the following order:
- A respiratory therapist will sit or lie on a medical bed and search for an artery in your inner wrist. When looking for an artery, they may use ultrasound imaging.
- Once they’ve found an artery, they’ll disinfect and clean the area.
- A tiny needle will be inserted into your artery to collect a sample of your blood.
You might experience some discomfort as the needle is inserted into your artery.
- A small amount of blood will be collected in a syringe after the needle is inserted.
- To stop the bleeding, they’ll remove the needle and place a cotton ball or gauze on the site. If you’re on a blood thinner, they may need to apply pressure for up to 10 minutes.
- You’ll be done after they apply a bandage to the wound.
Pulse oximeter-based blood oxygen saturation testing involves the following steps:
- A pulse oximeter is a small, plastic electronic device that is clipped to a part of your body — usually your fingertip — by your healthcare provider.
- The light that is infrared will pass through your skin and into your capillaries, where it will be measured. You won’t feel a thing from this.
- It then measures how much light is reflected off the hemoglobin molecules that make up the majority of your blood’s oxygen supply. Your blood oxygen level is determined by this.
- You’ll get a heart rate and oxygen level reading from the oximeter in a matter of seconds.
Pulse oximeters can also be used in the comfort of your own home. Pulse oximeter readings can be inaccurate due to a number of factors, including:
- A finger or toe that has been painted with nail polish.
- The oximeter should be used in a room with high-intensity lighting.
- The oximeter should not be moved around too much while you’re using it.
What should I expect after my blood oxygen level test?
Bruising and/or soreness at the site of the needle injection are common after a blood draw. After the blood is drawn, your doctor may advise you to avoid lifting anything heavy for 24 hours.
What do the results of a blood oxygen level test mean?
Test results for blood oxygen levels, for example, typically include the following:
- What was measured in your blood or the name of the blood test.
- Your blood test result in the form of a number or measurement.
- Typically used measurement range.
- Indicators that tell you if your results are within the normal range.
There are a number of possibilities if you have abnormal blood oxygen levels.
- Take in insufficient oxygen.
- Too much carbon dioxide is being emitted into the atmosphere.
- The pH of your blood is either too acidic or basic.
A blood oxygen level test can’t tell you what’s wrong with your health. To confirm or rule out a diagnosis, your healthcare provider may order additional tests.
What is a normal blood oxygen level?
A blood oxygen level test may have different reference ranges for the various aspects of your blood that are measured in the blood test. For each measurement, you’ll receive a summary of the lab’s normal ranges when you receive your blood test results back. Inquire with your doctor if you have any concerns or questions about your test results.
Pulse oximeter readings of between 95 and 100 percent are considered normal for most people. Normal oxygen saturation may be lower if you have a lung disease like COPD or pneumonia. It is up to you to ask your doctor or other medical professional what levels are acceptable in your system. If you live in an area with a high altitude, your oxygen saturation levels may also be lower than they should be.
You should be aware of the fact that pulse oximeters can be inaccurate. The oximeter’s reading may be 2 to 4% higher or lower than your actual blood saturation level. A blood test to measure your blood oxygen levels may provide a more precise reading from your doctor.
What does a low blood oxygen level mean?
Hypoxemia is the medical term for an abnormally low blood oxygen level. If you’re experiencing hypoxemia, you may want to seek immediate medical attention. Tissue and organ damage increases with a fall in oxygen saturation.
Oxygen delivery to the blood can be hampered by a wide range of medical conditions and circumstances. Hypoxemia (low blood oxygen levels) can be caused by a number of different things.
- Heart conditions.
- Lung conditions such as asthma, emphysema, and bronchitis.
- Strong pain medications or other problems that slow breathing.
- Sleep apnea (impaired breathing during sleep).
- Inflammation or scarring of your lung tissue.
- Locations of high altitudes, where oxygen in the air is lower.
There are many reasons why your healthcare provider might order additional testing if you have a low blood oxygen level. Only by measuring the oxygen levels in the blood can the root cause be discovered.
When should I know the results of my blood oxygen level test?
The results of an oxygen level test on a blood sample are usually available immediately (within minutes). Within seconds, a pulse oximeter can tell you how well your blood is oxygenated.
When should I call my doctor?
To the extent that you’re using an oximeter at home and your oxygen saturation level falls below 92 percent, contact your healthcare provider. As soon as you notice it’s below 88 percent, get to the nearest emergency room.
Asthma or COPD sufferers may need to see their doctor on a regular basis to ensure that their treatment is working. Call your doctor immediately if you notice any unusual symptoms related to your lung condition.
It’s not necessary to regularly check your blood oxygen level unless you have an underlying health condition that can affect your body’s ability to take in oxygen. Pulse oximeters can be useful in some situations, but they are not as accurate as blood tests for checking your blood oxygen levels. Consult your doctor right away if you notice any signs of low blood oxygen levels or difficulty breathing.