Everyone Should Know About Blood Oxygen Levels.

Everyone Should Know About Blood Oxygen Levels.

What are Blood Oxygen Levels?

The amount of oxygen in the blood circulating in the body is called the blood oxygen level. The oxygen in the blood is carried by a specific type of cell called the Red Blood Cells (RBCs) that transport the oxygen from the lungs to different body parts. As we know, oxygen is an essential element for the proper functioning of our organs. Thus, the quantitative value of the person’s oxygen levels determines the lung function and the distribution in the body.

                 

What is oxygen saturation (SpO₂)?

‘S’ in Sp0₂ refers to saturation,

‘p’ in Sp0₂ refers to pulse or pulsatile flow,

‘0₂’ in Sp0₂ refers to Oxygen,

Oxygen saturation measures the percentage of oxyhemoglobin (oxygen-bound hemoglobin) in the blood, and it is represented as arterial oxygen saturation (SaO2) and venous oxygen saturation (SvO2). Oxygen saturation is a vital parameter to define blood oxygen content and oxygen delivery.

Each hemoglobin molecule contains four heme groups that can readily bind molecular oxygen present in the blood. This means that a hemoglobin molecule can bind up to four oxygen molecules during transport in the blood.

Why Oxygen Saturation is Measured?

Healthcare providers measure oxygen saturation because it provides information about a patient’s state of health. The body’s tissues and organs require oxygen for metabolism, and oxygen saturation can reveal whether there is sufficient oxygen in the blood or whether the patient is in a state called hypoxemia (insufficient oxygen in the blood).

Oxygen saturation levels can influence clinical decisions about whether the patient is receiving sufficient oxygen and/or requires supplemental oxygen. Oxygen saturation levels are also monitored during and after surgeries and treatments and to assess a client’s capacity for increased activity.

 

Blood oxygen levels are measured in two ways.

Arterial Blood Gas (ABG)

Arterial blood gas (ABG) is a blood test that measures the oxygen level in your blood. It can detect the level of other gases in the blood, including the pH (acid/base) level. ABG test is very accurate, but it is invasive.

To get an ABG measurement, blood will be drawn from the artery rather than the vein. Unlike the veins, arteries have a pulse which can be felt. In addition, blood drawn from the arteries is oxygenated while the blood in the veins is not.

The artery in the wrist is used, as it can be felt easily compared to others in our body.

Since the wrist is a sensitive region, drawing blood from there is more uncomfortable compared to the vein near the elbow. Also, arteries are deeper than veins, adding to the discomfort.

Pulse Oximeter (Pulse Ox)

A pulse oximeter or pulse ox is a non-invasive device that measures the amount of oxygen in the blood by sending infrared light into capillaries in your finger, earlobe, or toe. And then it estimates how much light is reflected off the gases.

A reading shows what percentage of the blood is saturated, called SpO2 level. However, this test has a 2% error window, which means the reading can be as much as 2% higher or lower compared to your actual blood oxygen level.

A pulse oximeter test can be slightly less accurate, but very easy for physician to perform. That is why doctors rely on this test for fast readings.

As a pulse oximeter is non-invasive, you can perform this test by yourself.

                        

What are Normal Oxygen Saturation Levels?

Your blood oxygen measurement is called oxygen saturation level. In medical language, you may hear it called, SpO2 (O₂ sat) when using pulse oximeter and PaO₂ while using a blood gas.

Normal: A normal ABG oxygen level for individuals with healthy lungs falls between 80 and 100 mm Hg (millimeters of mercury). If a pulse oximeter measured the blood oxygen level (SpO2), normal reading is typically between 95 and 100 percent.

The medical condition, where the blood oxygen level of an individual is less than average, is also referred to as hypoxemia. During hypoxemia, the body has difficulty delivering oxygen to the organs and tissues.

What happens when your blood oxygen level falls?

When blood oxygen falls below 75 mmHg, the condition is generally termed as hypoxemia. If it further falls down to 60 mmHg, it may call for emergency support and a supplemental oxygen may be provided through an oxygen cylinder.

Severe decrease in blood oxygen levels may lead to several symptoms that the body experiences. These are:

·         Headache

·         Restlessness

·         Chest pain

·         Shortness of breath

·         Confusion

·         Lack of coordination

·         Dizziness

·         High blood pressure

·         Rapid beating of the heart

What are the Causes of Low Blood Oxygen Levels?

Lower blood oxygen levels or hypoxemia, a condition where the blood transports very little oxygen to other parts of the body, occur for various reasons. Low blood oxygen levels can occur due to the following reasons:

·         A general lack of oxygen in the air.

·         Difficulty breathing, thereby preventing the lungs from inhaling and circulating oxygen

·         Reduced ability of the bloodstream to circulate the oxygen to the lungs.

·         This is also due to the less intake of oxygen while breathing. This medical condition is a cause for concern and can lead to various complications within the body.

 

How to prevent hypoxemia or low blood oxygen levels?

 

A drop in oxygen saturation below the critical level should be treated with oxygen supplementation. Depending on the severity of the condition, a physician can prescribe supplemental oxygen, which has the most direct effect on the oxygen saturation level.  

However, for mild-to-moderate conditions, there are natural ways to increase the level of blood oxygen saturation. For example, a daily physical exercise can improve the lung capacity for gaseous exchange and protect against hypoxemia.

·         Deep breathing exercises and yoga are wonderful ways to calm your nerves and bring your oxygen-saturated blood levels to normal.

·         Staying hydrated also normalizes your blood oxygen levels and keeps it steady.

·         If you're a smoker, you must quit it before it takes a toll on your blood oxygen levels.

·         Eating a healthy and balanced diet can also help improve blood oxygen saturation. Since iron deficiency is one of the major causes of low oxygen saturation, eating foods that are rich in iron, such as meat, fish, kidney beans, lentils, and cashew nuts, can be helpful.

COVID-19 and Blood Oxygen Levels

In the current COVID-19 pandemic situations, where lung damage may lead to lower blood oxygen levels, monitoring the oxygen levels is an essential part of the treatment and recovery. In many cases, you may experience a decrease in oxygen levels even if you may not display the usual symptoms of COVID-19.