Oxygen Saturation

Oxygen is a vital need for every living entity. But the measurement of the oxygen level contained in our blood, the water we drink or the air we breathe can be known by the term oxygen saturation. The relative measurement of the oxygen content that is carried or dissolved in a given medium is termed as oxygen saturation.
The normal human body needs a constant oxygen supply for healthy functioning. Low oxygen saturation levels identified in blood can lead to serious and life threating medical conditions. Normal oxygen levels in body range between 95-100% at sea level. Oxygen saturation can be measured by a small device called, Oximeter. The precision and accuracy of the measurement is based on various factors like hemoglobin level, percentage of inhaled oxygen, oxygenation capacity of the person. With the above factors and recordings by oximeter, an oxygen saturation curve can be achieved. This curve plots the oxygen saturation against the partial pressure of oxygen giving the p50 value. This value indicates the point where the hemoglobin has a 50% oxygen saturation value. With the help of this value, one can assess the index of oxygen affinity in blood. For a healthy human, the clinically accepted oxygen saturation level is 95% although the saturation value may vary from 97% to 99%.
Oxygen saturation can be tested by two methods. One of them is by fitting a finger clip on your finger. The clip shines a light through a side of the finger and the light is measured from the other end by a detector. Blood cells with different levels of oxygen saturation exhibit a different color. Blood cells give a bright red color if they are loaded with oxygen. Else the color is a bluish tinge indicating that there is not enough oxygen in the blood cell. The finger clip gives a rough estimate of oxygen saturation value which is not precise. The better alternative is to go for an arterial blood gas test. Usually, for blood tests, blood is drawn from veins. In this test, however, blood is drawn from arteries (the artery for blood test is mostly in the wrist). This test provides with the exact value of the oxygen saturation. Both these procedures yield fast results with the former being available immediately and later, being available in a span of 15 minutes.