CPR First Aid

Is Low Blood Oxygen Levels (SpO2) Dangerous?

Low blood oxygen levels, also known as SpO2, are conditions where there is not enough oxygen in the blood. Because of this, the body’s cells and tissues may not be able to function properly. In some cases, low blood oxygen levels can be dangerous. It is important to understand the signs and symptoms of low blood oxygen levels so that you can get treatment if needed.

What is Oxygen Saturation Level?

Oxygen saturation of the blood is defined as the percentage of haemoglobin molecules in the blood that carries oxygen. The term is a measure of the amount of oxygen bonded to haemoglobin cells inside the circulatory system, expressed as a percentage in the oximeter reading, with a normal adult having a value of 96 percent.

Blood oxygen: % of hemoglobin carrying O2. Measure in oximeter: % reading. Normal: 96%.

Normal SpO2 Levels

SpO2 is generally a good indicator of how well your lungs are functioning and how much oxygen is being delivered to your tissues. Normal levels typically fall in the range of 95-100%. Anything below 90% is considered low and may require medical intervention. SpO2 is a measurement that shows how well a patient is breathing and distributing blood throughout the body.

How is it Measured?

It is typically measured with a pulse oximeter, which uses light to measure the amount of oxygen in your blood. The device has a computerised monitor and a probe to measure SpO2. The patient’s finger, toe, nostril, or earlobe may receive the probe, and the amount of oxygen in the patient’s blood is then shown by a measurement on the monitor. It does this by employing an audio signal that correlates to the patient’s pulse and a wave shape that may be visually viewed. As the blood saturation drops, so does the signal’s tone. The monitor additionally displays heart rate, and a high/low saturation level alarm is also accessible to notify the caregiver.

Also available in Southport and anywhere in Australia are portable pulse oximeters that are reliable for home monitoring, especially during Covid-19. If your workplace requires emergency response staff, you may be interested in furthering your knowledge of Southport first aid. Send your enquiry to CPR First Aid and we’ll be happy to answer your questions.

Oxygen level checked with a pulse oximeter, using light to gauge blood oxygen. Device: monitor & probe for SpO2. Probe on finger, toe, nostril, or earlobe. Monitor displays oxygen level.

Factors that Can Affect SpO2

Oxygen saturation is an important indicator of oxygen distribution to the tissues and organs, as well as it can be used to help diagnose and treat various respiratory and cardiovascular conditions. There are many factors, such as the following, that can affect oxygen saturation levels.

Physical Activity and Exertion

The level of activity that a person is engaged in. Higher levels of activity will result in greater oxygen consumption and therefore lower oxygen saturation levels.

High Altitude

The altitude at which a person is living or travelling. Oxygen saturation levels will typically be lower at higher altitudes due to the reduced level of oxygen in the air.

Underlying Conditions

Any medical condition that a person may have which affects their ability to breathe properly or transport oxygen around the body effectively. Conditions such as COPD, heart disease, and anaemia can all lead to lower oxygen saturation levels.


The use of certain medications can affect the way the body uses or transports oxygen. For example, some asthma medications can cause oxygen saturation levels to drop.

Cigarette Smoking

Smoking cigarettes. The combustion of tobacco produces carbon monoxide. When gasoline, wood, propane, charcoal, or other fuels are burned, there is the production of carbon monoxide, which is an odourless, tasteless gas that competes with oxygen for binding sites on haemoglobin leading to reduced oxygen saturation levels.

Low Oxygen Levels in Southport QLD

In Queensland and Australia, there are a few potential causes of low oxygen saturation in the blood, but the most common one is simply being at high altitudes. When you’re at a higher altitude, there is less oxygen in the air, which means that your body has to work harder to get the oxygen it needs. This can lead to low oxygen saturation levels in the blood. Other potential causes include certain medical conditions that make it difficult for the body to absorb oxygen or that cause the body to use oxygen more quickly than normal. 

Smoking is also a common cause of low oxygen saturation, as it can damage the lungs and make it harder for them to take in oxygen. Finally, certain medications can also cause low oxygen saturation levels. If you’re on any medication that affects the way your body uses or absorbs oxygen, it’s important to talk to your doctor about the potential risks.

Common Conditions that Can Lower Oxygen Saturation Levels

Let us take a deep dive into the several underlying conditions that can contribute to the decrease in oxygen saturation in the body.

  • Pulmonary embolism – is a condition in which a blood clot blocks the pulmonary artery, preventing oxygen-rich blood from flowing to the lungs.
  • Bronchitis – is an inflammation of the bronchial tubes, which are the airways that carry air to and from the lungs. This can cause a buildup of mucus, which can make it difficult to breathe and lower oxygen saturation levels.
  • Pneumonia – is an infection of the lungs that can cause them to fill with fluid, making it difficult for oxygen to reach the blood.
  • Congestive heart failure – is a condition in which the heart is unable to pump enough blood to meet the body’s needs. This can cause fluid to build up in the lungs, making it difficult to breathe and lowering oxygen saturation levels.
  • Asthma – is a chronic condition that causes the airways to narrow, making it difficult to breathe. This can also lower oxygen saturation levels.
  • Chronic obstructive pulmonary disease (COPD) – is a group of conditions that includes emphysema and chronic bronchitis. It is characterized by a progressive decline in lung function, which can make it difficult to breathe and lower oxygen saturation levels.
  • Sleep apnea – a condition in which a person stops breathing for brief periods during sleep. This can cause oxygen levels to drop and lead to fatigue during the day.
  • Anaemia – is a condition in which the blood does not have enough healthy red blood cells to carry oxygen to the body’s tissues. This can lead to fatigue and shortness of breath and can lower oxygen saturation levels.
  • Cyanotic heart disease – is a group of conditions that affect the heart’s ability to pump blood properly. This can cause oxygen-poor blood to back up in the body, leading to a bluish tint to the skin and low oxygen saturation levels.
  • Pulmonary fibrosis – is a condition in which the lungs become scarred and thickened, making it difficult to breathe. This can lead to low oxygen saturation levels.

Exploring conditions that drop oxygen saturation in the body.

Complications Brought About by Low Blood Oxygen Levels

If oxygen levels do not return to normal levels after several readings and if left untreated, certain complications can happen.

  1. Low oxygen saturation levels can cause a decrease in blood pressure, which can lead to lightheadedness, dizziness, and fainting.
  2. Oxygen deprivation can also lead to an irregular heartbeat, and in severe cases, heart failure.
  3. Lung damage and respiratory failure are also possible complications of low oxygen saturation levels.
  4. Oxygen deprivation can also cause neurological damage, including seizures, coma, and even death.
  5. In pregnant women, low oxygen saturation levels can lead to miscarriage, premature labour, and stillbirth.
  6. Lastly, low oxygen saturation levels can cause fatigue, weakness, and confusion. If you experience any of these symptoms, call triple zero (000)  immediately.


SpO2, or arterial oxygen saturation, represents a measurement of the quantity of oxygen that attaches to the haemoglobin cells in the circulatory system. It is a measure of the amount of oxygen in your blood.

If you are with a patient who has low oxygen saturation (below 90%), it is important to seek medical attention immediately and bring the patient down to a lower altitude if possible. In the meantime, supplemental oxygen may be given if available. If the patient is unconscious, they will need to be placed in the recovery position and given CPR if necessary. It is also important to monitor the patient’s vital signs and keep them warm.

If you are interested in enrolling in a CPR and first aid course at Cnr Ferry Rd and, Cotlew St E, Southport 4215, contact CPR First Aid RTO 21903, a leading provider of compliant and nationally accredited first aid courses delivered all across Australia.

Subscribe now & receive Exclusive DISCOUNTS on your booking!



More Posts

The answer is simple: DRSABCD is an easy way to remember the order of first aid steps when someone is injured.

What does DRSABCD stand for?

Imagine you are at work and someone falls ill. What should you do? Well, the answer may be simpler than you think – according to