Saturation – what is it and what affects it? How to test the saturation?

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Saturation is an indicator of the saturation of peripheral blood hemoglobin with oxygen. Its level can be checked with a pulse oximeter. When saturation drops, we usually start to feel short of breath. The oxygen saturation test is safe and often used by doctors to monitor the patient’s condition during various procedures or operations.

Saturation – what is it?

Saturation is an indicator of hypoxia in the body. The word comes from the Latin “saturato”, which means to saturate a liquid with gas. In medicine, oxygen saturation in the blood is determined in this way. Patients sometimes report shortness of breath. As a result, saturation is usually the first parameter that changes. However, it should be remembered that dyspnoea does not always mean a decrease in saturation.

See: What to do when you have an attack of breathlessness?

Saturation – what does it depend on?

Understanding how blood is saturated with oxygen starts with the alveoli, or air sacs. There are millions of such microscopic air sacs in the lungs. They play an important role: exchanging oxygen and carbon dioxide molecules in and out of the bloodstream.

As oxygen molecules pass through the alveoli of the lungs, they bind with hemoglobin, a substance in the blood.

As hemoglobin is circulating, oxygen essentially stops and is discharged into the body’s tissues. This allows hemoglobin to trap carbon dioxide from the tissues and transport it back to the vesicles so that the cycle can begin anew.

Blood oxygen levels depend on several key factors:

1. the amount of oxygen we inhale,
2. the work of the alveoli – how well the alveoli convert carbon dioxide into oxygen,
3. the amount of hemoglobin that is concentrated in red blood cells,
4. how well hemoglobin attracts oxygen.

Most of the time, hemoglobin contains enough oxygen to meet the body’s needs. However, some diseases reduce its ability to bind with oxygen.

Saturation – factors affecting oxygen saturation

Blood disorders, circulation problems, and lung problems can prevent your body from absorbing or transporting enough oxygen. This, in turn, can lower the blood oxygen saturation level.

Examples of conditions that can affect saturation include:

1. respiratory tract infections (e.g. colds, flu, COVID-19), as they can affect breathing and thus the oxygen level in the body,
2. chronic obstructive pulmonary disease (COPD),
3. bronchial asthma – a chronic lung disease that causes the airways to narrow
4. pneumothorax – partial or complete collapse of the lung,
5. anemia – not enough healthy red blood cells
6. heart disease – a group of diseases that affect the work of the heart,
7. pulmonary embolism – when a blood clot causes a blockage in the pulmonary artery,
8. congenital heart disease – a structural heart defect that occurs at birth.

The editorial board recommends: Pulmonary embolism in COVID-19 – a side effect of the coronavirus

How to test the saturation?

The saturation level can be checked safely and easily. Pulse oximetry is an effective method of measuring the oxygen saturation of arterial hemoglobin in blood. The pulse oximeter is put on the finger. In this device, a special sensor measures the absorption of radiation from the transmitter by the red blood cells. The saturation result is obtained as a percentage and it is the amount of hemoglobin saturated with oxygen.

You can also buy a pulse oximeter and test it yourself, so you can constantly monitor the saturation. On Medonet Market you will find the Vitammy o2 connect pulse oximeter with Bluetooth at a promotional price.

Saturation test – pulse oximetry

It is a test that tests the saturation, i.e. the saturation of a liquid with gas. Controlling the level of saturation helps to contain the developing respiratory failure.

The oximeter sensor can be attached to:

1. finger or toe,
2. auricle,
3. wing of the nose,
4. forehead,
5. in newborns, the foot or wrist.

This device, apart from testing the saturation, can also measure and record the pulse, i.e. the heart rate.

Saturation – indications for the study

Saturation testing is quick and easy to perform. For this reason, in many cases, the assessment of saturation is carried out in patients in the hospital. The most common indication for testing its level is:

1. suspicion of its reduction,
2. respiratory failure,
3. control of saturation in mother and fetus,
4. bronchoscopy,
5. qualifying the patient for oxygen therapy,
6. operations and postoperative period,
7. child anesthesia,
8. patient in serious condition,
9. hospitalization of the patient,
10. ventilation of one lung.

Do you want to monitor your saturation at home? Order an easy-to-use pulse oximeter from the Medonet Market offer.

Saturation – the operation of a pulse oximeter

The saturation test is performed by placing, for example, a pulse oximeter sensor on the nasal lobe. It is important to keep your nose warm if it is cold as there is low blood flow in such places and the results of oxygen saturation may be falsified. Saturation determination is performed on the basis of transmission spectrophotometry.

The sensor emits radiation that is partially absorbed by the blood flowing through the blood vessels. The built-in photodetector measures the return signal, which consists of two components, a constant and a variable. The variable component, otherwise pulsating, describes the saturation.

See: Pulmonary arterial hypertension is no longer a fatal disease

Saturation – norms

Normal oxygen saturation of blood is about 95-98%. In people undergoing oxygen therapy, the saturation is 98-100%. It is worth knowing that in smokers the saturation is lower than in non-smokers.

If the results of the saturation measurement are disturbing, it may be necessary to consult a doctor immediately. If this is the case, it’s a good idea to discuss your condition through the haloDoctor video chat advice (also available in the evenings and at weekends).

Saturation below normal is below 90% and is usually a sign of severe respiratory failure. However, it should be remembered that even if the saturation is high, the oxygen value at the oxygen level may be low. The saturation test does not refer to the oxygen metabolism in cells.

Read: When is breathlessness a serious illness?

What happens when saturation drops?

Lower than normal blood oxygen levels are known as hypoxemia. In general, an oxygen saturation level of less than 90% is considered hypoxemiawhich may result from cardiopulmonary complications, sleep apnea, certain medications, and exposure to high altitude.

The most common symptoms of hypoxemia are headache, rapid heartbeat, coughing, shortness of breath, wheezing, confusion, and a bruise of the skin and mucous membranes (cyanosis).

Cyanosis is a pathological condition characterized by extremely low oxygen saturation. There are two types of cyanosis: central cyanosis and peripheral cyanosis. In central cyanosis, the oxygen saturation level drops below 85%, which causes a bluish tinge to appear all over the skin and visible mucosa.

In peripheral cyanosis, which often occurs due to increased oxygen uptake by peripheral tissues, the bluish tinge only appears on peripheral parts of the body, such as the hands and feet. The most common causes of peripheral cyanosis are venous stasis, low cardiac output, or extreme cold.

See: What are blue lips evidencing?

Saturation – how to improve it?

A fall in oxygen saturation below the critical level should be treated with oxygen supplementation. Depending on the severity of your condition, your doctor may prescribe supplemental oxygen that has the most direct effect on your oxygen saturation level.

However, for mild to moderate decreases in oxygen saturation, there are natural ways to increase the oxygen saturation level in your blood. For example, daily exercise can improve the gas exchange capacity of the lungs and protect against hypoxemia. However, it is important to consult your doctor before beginning any exercise regimen or making changes to your daily exercise routine.

A healthy and balanced diet can also help improve your blood’s oxygen saturation. Since iron deficiency is one of the main causes of low oxygen saturation, eating foods high in iron may be helpfulsuch as meat, fish, beans, lentils, and cashews.

Saturation – what raises it?

The result of the saturation test is not always true. The disturbed saturation result will be influenced by:

1. the use of factors impeding the flow of peripheral blood,
2. low tissue perfusion,
3. measurement in a cold place,
4. lack of body control, e.g. seizures
5. hemoglobin level disturbances,
6. type of light in the room,
7. various changes on the nails, e.g. dark varnish or mycosis.