What Is Oxygen Saturation?

When people discuss oxygen saturation levels, they are referring to the extent of haemoglobin that is saturated with oxygen. Oxygen saturation levels can be determined by medical professionals via a pulse oximetry, a non-invasive technique. The patient will have a disposable sensor placed on their forehead, earlobe, fingertip or bridge of the nose. A normal oxygen saturation level is between 95% to 100%.

Low Oxygen Saturation Levels

Oxygen levels falling below 90% are typically seen as abnormal, thereby indicating cause for concern. A drop in oxygen saturation levels is known as desaturation and there are many possible causes. When your blood oxygen levels fall very low, you have hypoxemia. Hypoxemia is characterized by a palpable shortness of breath.

Symptoms of Low Oxygen Saturation Levels

There are a few symptoms that will accompany low saturation levels, they are as follows:

  • Cyanosis - This is perhaps the most familiar and distinctive symptom of low oxygen saturation levels. Cyanosis is a physical symptom that causes the skin or mucous membranes of the human body to turn bluish in colour. This occurs because less oxygen is reaching the body tissue. This bluish tint will most likely be apparent on the beds of the fingernails and toenails, as well as the lips and tongue.
  • Shortness of breath - This is another common and characteristic symptom of low oxygen saturation levels. It will typically come on very suddenly and be quite overwhelming, as the effected individual will be gasping for air.
  • Extreme fatigue and weakness - It will feel as if your energy has been completely depleted. You will most likely wish to remain in bed rather than go about your normal daily activities.
  • Mental confusion - You may experience bouts of confusion and lowered dexterity. Since there are lower oxygen levels in your blood, there is ultimately less oxygen reaching your brain. You will therefore experience detrimental effects to cognition.
  • Headache - Low blood oxygen saturation levels can also cause painful headaches.

Causes of Low Oxygen Saturation Levels

Low oxygen saturation levels can be due to a number of different medical conditions. Below we have listed a few.

1. Thin Air

  • High altitudes: The heightened altitude can cause desaturation of a person's blood. This occurs because the air is thin (a high altitude is typically classified as anything above 3000 m or around 10,000 ft.).

2. Blood Oxygen Transportation Dysfunction

  • Anemia: This is a medical condition where an individual doesn't have enough red blood cells to carry sufficient amounts of oxygen to their body tissues. This causes low oxygen levels in the blood and an intense sensation of exhaustion.

3. Air Way Obstruction

  • Airway obstruction: This can either be a partial or full blocking of a person's airways. This obtrusion can be caused by foreign material that has become lodged in an airway, an allergic reaction, infections, anatomical irregularities, or trauma.
  • Chronic obstructive pulmonary disease: This is an umbrella term encompassing any lung disease that blocks airflow upon exhalation, consequently making it harder to breathe. The infected person will therefore have lower levels of oxygen in their blood.
  • Sleep apnea: Breathing stops and starts periodically during sleep. Because the person is ceasing to breathe for a short period of time, less oxygen is inhaled and they can experience a low blood oxygen saturation level.

4. Alveoli Destruction

  • Emphysema: The air sacs in your lungs are systemically destroyed, making it harder to exchange oxygen from air sacs with carbon dioxide from the blood stream; a decreased oxygen saturation level results.
  • Acute respiratory distress syndrome (ARDS): This will occur when there is a fluid build-up in the alveoli, which are miniature, pliant air sacs in your lungs. This fluid build-up will cause a decrease in oxygen levels in your blood.

Furthermore, specific medications can cause a low oxygen saturation level. These include narcotics and anesthetics.

High Oxygen Saturation levels

Blood oxygen saturation levels cannot exceed 100% and no one can obtain this high level of oxygen just breathing natural air. The only way for this to occur is to breathe from medical oxygen supplements. However, inhaling high oxygen flow for an extended period may have adverse effects. Eyesight damage due to retinopathy is one such concern, which can lead to blindness.

What can you do then?

If you are experiencing any of the aforementioned symptoms, be sure to contact a health professional to test your blood saturation level and determine the cause.