Oximeter - Blood Oxygen level reader - X-PLOR Oxygen Concentrator

What to Know About Low Blood Oxygen Levels

When your blood oxygen level is low, the organs in your body are receiving less oxygen which can negatively impact their bodily function.

Oxygen is a gas that is vital to human life. It is one of the gases that is found in the air we breathe. If you have a chronic lung disease limiting the effectiveness of your lungs, you may need supplemental oxygen for your organs to function normally.

Low levels of oxygen in the blood are referred to as hypoxemia. Hypoxemia is a  below-normal level of oxygen in your blood, specifically in the arteries.

How is Hypoxemia Measured?

Hypoxemia is determined by measuring the oxygen level in a blood sample taken from an artery, called an arterial blood gas. It can also be estimated by measuring the oxygen saturation of your blood using a pulse oximeter. A pulse oximeter is a small device that can fit on your finger and measure your blood oxygen level.

What is the Normal Level?

There is no singular ‘normal’ oxygen level, as people have different needs based on their health conditions. If a person has no previous medical issues, a normal pulse oximeter reading usually ranges from 95 to 100 percent.

If you suffer from a respiratory or cardiac condition, your healthcare provider may recommend a lower acceptable range anywhere from 88 to 92 percent. Always clarify with your healthcare provider what blood oxygen level range they want you to stay within.

What Causes Hypoxemia?

Several factors can contribute to the low levels of oxygen in a person’s blood. Ideally, there should be enough oxygen in the air we breathe. Our lungs must be able to inhale oxygen-rich air and our bloodstream needs to be able to properly circulate our blood to our lungs so that it can take in oxygen and deliver it to our vital organs.

Common causes of hypoxemia include:

  • Anemia- a condition where your body lacks enough red blood cells to carry oxygen to your body’s tissues
  • Asthma- due to the narrowing and swelling of the airways in your lungs
  • Chronic obstructive pulmonary disease (COPD)- due to inflammation in the lungs
  • Pneumonia- due to the infection and the lungs filling with fluid
  • Pulmonary Fibrosis- due to the increased scarring of the lungs
  • Sleep apnea- when a person has a momentary pause in breathing, low oxygen levels can occur

There can be several other causes of hypoxemia. If you have a pulse oximeter and monitor your levels regularly, be sure to talk to your healthcare provider if you are experiencing low blood oxygen levels.

Symptoms of Hypoxemia

Just as the causes of hypoxemia vary, so do the symptoms. Depending on the severity of your condition, you may experience the following symptoms:

  • Shortness of breath- the hallmark symptom
  • Coughing
  • Headache
  • Confusion
  • Fast heart rate
  • Wheezing


Always contact your healthcare provider as soon as possible if you experience shortness of breath with slight exertion or even at rest. If your shortness of breath comes on suddenly and you are feeling your heart is beating fast and you cannot get enough air in, seek emergency care as this could be a life-threatening situation.

To maintain healthy oxygen levels, it is important to stop smoking if you are a current smoker, avoid secondhand smoke, and get regular exercise to strengthen your lungs.