Oxymetry is a test that measures the oxygen saturation of the blood, i.e. the percentage of oxygen transported into the bloodstream. This test is important when suspected of diseases that disrupt or interfere with lung function, heart disease or neurological diseases, for example.
Generally, an oximetry greater than 90% indicates good oxygenation of the blood, however, it is necessary for the doctor to evaluate each case. Low blood oxygenation rates may indicate the need for treatment in the hospital with oxygen and may indicate a life-threatening condition if not corrected properly. Understands the consequences of lack of oxygen in the blood.
There are two ways to measure oxygen saturation
This is the most commonly used way to measure oxygen saturation, as it is a noninvasive technique that measures the amount of oxygen through a small device, called a pulse oximeter, which is placed in contact with the skin, usually at the tip of the finger.
The main advantage of this measure is that it is not necessary to collect blood, avoiding stings. In addition to oximetry, this device can also measure other vital data, such as the number of heartbeats and breathing rate, for example.
Pulse oximetry is widely used by physicians and other health professionals in clinical evaluation, particularly in cases of diseases that cause breathing difficulties, such as lung, heart and neurological diseases, or during anesthesia. The oximeter can also be purchased from medical or hospital supply stores and is available in different brands and prices.
Unlike pulse oximetry, arterial blood gas testing is an invasive way to measure the oxygen level in your blood, as it is done by drawing blood from a syringe, and a needle is needed. For this reason, this type of test is less common than pulse oximetry.
The advantage of arterial gasometry is a more accurate measure of oxygen saturation levels in the blood, as well as being able to provide other important measures, such as the amount of carbon dioxide, pH or the amount of acids and bicarbonate in the blood, for example.
This type of measurement is generally used only in cases where the patient needs to be monitored continuously or more accurately, which is more common in situations such as major surgery, severe heart disease, arrhythmias, generalized infections, sudden changes in blood pressure or respiratory failure. For example. Find out what respiratory failure is and how it can reduce blood oxygenation.
A healthy person, with adequate oxygenation of the body, usually has an oxygen saturation greater than 95%, however, it is common that due to benign conditions, such as colds or flu, saturation is between 90 and 95%, for no reason. Concern.
When saturation reaches values below 90%, this may indicate the presence of a more serious disease that can affect oxygen levels in the body, such as asthma, pneumonia, emphysema, heart failure or neurological diseases, for example.
In arterial gasometry, in addition to measuring oxygen saturation, partial oxygen pressure (Po2) is also evaluated, which should be between 80 and 100 mmHg.
It is very important that oxygen saturation devices are regularly calibrated to avoid negative results. In addition, when using the pulse oximeter, some precautions to avoid changing the test include:
Before performing the test, your doctor should also investigate other conditions such as anemia or impaired blood flow, which may interfere with measuring blood oxygenation.